[Java] Format ray java code (#13056)

bazel/ray.bzl

@@ -1,5 +1,4 @@
 load("@com_github_google_flatbuffers//:build_defs.bzl", "flatbuffer_library_public")
-load("@com_github_checkstyle_java//checkstyle:checkstyle.bzl", "checkstyle_test")
 load("@bazel_skylib//rules:copy_file.bzl", "copy_file")
 load("@bazel_common//tools/maven:pom_file.bzl", "pom_file")
 
@@ -77,14 +76,6 @@ def define_java_module(
         resources = native.glob([name + "/src/main/resources/**"]) + additional_resources,
         **kwargs
     )
-    checkstyle_test(
-        name = "io_ray_ray_" + name + "-checkstyle",
-        target = ":io_ray_ray_" + name,
-        config = "//java:checkstyle.xml",
-        suppressions = "//java:checkstyle-suppressions.xml",
-        size = "small",
-        tags = ["checkstyle"],
-    )
     if define_test_lib:
         test_lib_name = "io_ray_ray_" + name + "_test"
         pom_file_targets.append(test_lib_name)
@@ -93,14 +84,6 @@ def define_java_module(
             srcs = native.glob([name + "/src/test/java/**/*.java"]),
             deps = test_deps,
         )
-        checkstyle_test(
-            name = "io_ray_ray_" + name + "_test-checkstyle",
-            target = ":io_ray_ray_" + name + "_test",
-            config = "//java:checkstyle.xml",
-            suppressions = "//java:checkstyle-suppressions.xml",
-            size = "small",
-            tags = ["checkstyle"],
-        )
     pom_file(
         name = "io_ray_ray_" + name + "_pom",
         targets = pom_file_targets,

bazel/ray_deps_build_all.bzl

@@ -3,7 +3,6 @@ load("@com_github_ray_project_ray//java:dependencies.bzl", "gen_java_deps")
 load("@com_github_ray_project_ray//streaming/java:dependencies.bzl", "gen_streaming_java_deps")
 load("@com_github_nelhage_rules_boost//:boost/boost.bzl", "boost_deps")
 load("@com_github_jupp0r_prometheus_cpp//bazel:repositories.bzl", "prometheus_cpp_repositories")
-load("@com_github_checkstyle_java//:repo.bzl", "checkstyle_deps")
 load("@com_github_grpc_grpc//third_party/py:python_configure.bzl", "python_configure")
 load("@com_github_grpc_grpc//bazel:grpc_deps.bzl", "grpc_deps")
 load("@rules_proto_grpc//:repositories.bzl", "rules_proto_grpc_toolchains")
@@ -13,7 +12,6 @@ def ray_deps_build_all():
   bazel_skylib_workspace()
   gen_java_deps()
   gen_streaming_java_deps()
-  checkstyle_deps()
   boost_deps()
   prometheus_cpp_repositories()
   python_configure(name = "local_config_python")

bazel/ray_deps_setup.bzl

@@ -131,12 +131,6 @@ def ray_deps_setup():
         sha256 = "97e70364e9249702246c0e9444bccdc4b847bed1eb03c5a3ece4f83dfe6abc44",
     )
 
-    auto_http_archive(
-        name = "com_github_checkstyle_java",
-        url = "https://github.com/ray-project/checkstyle_java/archive/ef367030d1433877a3360bbfceca18a5d0791bdd.tar.gz",
-        sha256 = "847d391156d7dcc9424e6a8ba06ff23ea2914c725b18d92028074b2ed8de3da9",
-    )
-
     auto_http_archive(
         # This rule is used by @com_github_nelhage_rules_boost and
         # declaring it here allows us to avoid patching the latter.

ci/travis/format.sh

@@ -49,6 +49,7 @@ FLAKE8_VERSION=$(flake8 --version | head -n 1 | awk '{print $1}')
 YAPF_VERSION=$(yapf --version | awk '{print $2}')
 SHELLCHECK_VERSION=$(shellcheck --version | awk '/^version:/ {print $2}')
 MYPY_VERSION=$(mypy --version | awk '{print $2}')
+GOOGLE_JAVA_FORMAT_JAR=/tmp/google-java-format-1.7-all-deps.jar
 
 # params: tool name, tool version, required version
 tool_version_check() {
@@ -69,6 +70,15 @@ else
     echo "WARNING: clang-format is not installed!"
 fi
 
+if command -v java >/dev/null; then
+  if [ ! -f "$GOOGLE_JAVA_FORMAT_JAR" ]; then
+    echo "Java code format tool google-java-format.jar is not installed, start to install it."
+    wget https://github.com/google/google-java-format/releases/download/google-java-format-1.7/google-java-format-1.7-all-deps.jar -O "$GOOGLE_JAVA_FORMAT_JAR"
+  fi
+else
+    echo "WARNING:java is not installed, skip format java files!"
+fi
+
 if [[ $(flake8 --version) != *"flake8_quotes"* ]]; then
     echo "WARNING: Ray uses flake8 with flake8_quotes. Might error without it. Install with: pip install flake8-quotes"
 fi
@@ -112,6 +122,18 @@ GIT_LS_EXCLUDES=(
   ':(exclude)python/ray/cloudpickle/'
 )
 
+JAVA_EXCLUDES=(
+  'java/api/src/main/java/io/ray/api/ActorCall.java'
+  'java/api/src/main/java/io/ray/api/PyActorCall.java'
+  'java/api/src/main/java/io/ray/api/RayCall.java'
+)
+
+JAVA_EXCLUDES_REGEX=""
+for f in "${JAVA_EXCLUDES[@]}"; do
+  JAVA_EXCLUDES_REGEX="$JAVA_EXCLUDES_REGEX|(${f//\//\/})"
+done
+JAVA_EXCLUDES_REGEX=${JAVA_EXCLUDES_REGEX#|}
+
 # TODO(barakmich): This should be cleaned up. I've at least excised the copies
 # of these arguments to this location, but the long-term answer is to actually
 # make a flake8 config file
@@ -132,7 +154,6 @@ mypy_on_each() {
     popd
 }
 
-
 # Format specified files
 format_files() {
     local shell_files=() python_files=() bazel_files=()
@@ -205,6 +226,11 @@ format_all() {
       git ls-files -- '*.cc' '*.h' '*.proto' "${GIT_LS_EXCLUDES[@]}" | xargs -P 5 clang-format -i
     fi
 
+    echo "$(date)" "format java...."
+    if command -v java >/dev/null & [ -f "$GOOGLE_JAVA_FORMAT_JAR" ]; then
+      git ls-files -- '*.java' "${GIT_LS_EXCLUDES[@]}" | sed -E "\:$JAVA_EXCLUDES_REGEX:d" | xargs -P 5 java -jar "$GOOGLE_JAVA_FORMAT_JAR" -i
+    fi
+
     if command -v shellcheck >/dev/null; then
       local shell_files non_shell_files
       non_shell_files=($(git ls-files -- ':(exclude)*.sh'))
@@ -254,6 +280,12 @@ format_changed() {
         fi
     fi
 
+    if command -v java >/dev/null & [ -f "$GOOGLE_JAVA_FORMAT_JAR" ]; then
+       if ! git diff --diff-filter=ACRM --quiet --exit-code "$MERGEBASE" -- '*.java' &>/dev/null; then
+            git diff --name-only --diff-filter=ACRM "$MERGEBASE" -- '*.java' | sed -E "\:$JAVA_EXCLUDES_REGEX:d" | xargs -P 5 java -jar "$GOOGLE_JAVA_FORMAT_JAR" -i
+        fi
+    fi
+
     if command -v shellcheck >/dev/null; then
         local shell_files non_shell_files
         non_shell_files=($(git diff --name-only --diff-filter=ACRM "$MERGEBASE" -- ':(exclude)*.sh'))

java/api/src/main/java/io/ray/api/ActorHandle.java

@@ -1,11 +1,12 @@
 package io.ray.api;
 
 /**
- * A handle to a Java actor. <p>
+ * A handle to a Java actor.
  *
- * A handle can be used to invoke a remote actor method, with the {@code "call"} method. For
+ * <p>A handle can be used to invoke a remote actor method, with the {@code "call"} method. For
  * example:
- * <pre> {@code
+ *
+ * <pre>{@code
  * class MyActor {
  *   public int echo(int x) {
  *     return x;
@@ -19,11 +20,9 @@ package io.ray.api;
  * Assert.assertEqual(result.get(), 1);
  * }</pre>
  *
- * Note, the {@code "call"} method is defined in {@link ActorCall} interface, with multiple
+ * <p>Note, the {@code "call"} method is defined in {@link ActorCall} interface, with multiple
  * overloaded versions.
  *
  * @param <A> The type of the concrete actor class.
  */
-public interface ActorHandle<A> extends BaseActorHandle, ActorCall<A> {
-
-}
+public interface ActorHandle<A> extends BaseActorHandle, ActorCall<A> {}

java/api/src/main/java/io/ray/api/BaseActorHandle.java

@@ -3,15 +3,13 @@ package io.ray.api;
 import io.ray.api.id.ActorId;
 
 /**
- * A handle to an actor. <p>
+ * A handle to an actor.
  *
- * A handle can be used to invoke a remote actor method.
+ * <p>A handle can be used to invoke a remote actor method.
  */
 public interface BaseActorHandle {
 
-  /**
-   * @return The id of this actor.
-   */
+  /** Returns the id of this actor. */
   ActorId getId();
 
   /**

java/api/src/main/java/io/ray/api/ObjectRef.java

@@ -2,15 +2,14 @@ package io.ray.api;
 
 /**
  * Represents a reference to an object in the object store.
+ *
  * @param <T> The object type.
  */
 public interface ObjectRef<T> {
 
   /**
-   * Fetch the object from the object store, this method will block
-   * until the object is locally available.
+   * Fetch the object from the object store, this method will block until the object is locally
+   * available.
    */
   T get();
-
 }
-

java/api/src/main/java/io/ray/api/PyActorHandle.java

@@ -1,18 +1,11 @@
 package io.ray.api;
 
-/**
- * Handle of a Python actor.
- */
+/** Handle of a Python actor. */
 public interface PyActorHandle extends BaseActorHandle, PyActorCall {
 
-  /**
-   * @return Module name of the Python actor class.
-   */
+  /** Returns the module name of the Python actor class. */
   String getModuleName();
 
-  /**
-   * @return Name of the Python actor class.
-   */
+  /** Returns the name of the Python actor class. */
   String getClassName();
 }
-

java/api/src/main/java/io/ray/api/Ray.java

@@ -12,16 +12,12 @@ import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.Callable;
 
-/**
- * This class contains all public APIs of Ray.
- */
+/** This class contains all public APIs of Ray. */
 public final class Ray extends RayCall {
 
   private static RayRuntime runtime = null;
 
-  /**
-   * Initialize Ray runtime with the default runtime implementation.
-   */
+  /** Initialize Ray runtime with the default runtime implementation. */
   public static void init() {
     try {
       Class clz = Class.forName("io.ray.runtime.DefaultRayRuntimeFactory");
@@ -30,7 +26,6 @@ public final class Ray extends RayCall {
     } catch (Exception e) {
       throw new RuntimeException("Failed to initialize Ray runtime.", e);
     }
-
   }
 
   /**
@@ -45,9 +40,7 @@ public final class Ray extends RayCall {
     }
   }
 
-  /**
-   * Shutdown Ray runtime.
-   */
+  /** Shutdown Ray runtime. */
   public static synchronized void shutdown() {
     if (runtime != null) {
       internal().shutdown();
@@ -57,7 +50,8 @@ public final class Ray extends RayCall {
 
   /**
    * Check if {@link #init} has been called yet.
-   * @return True if {@link #init} has already been called and false otherwise.
+   *
+   * <p>Returns True if {@link #init} has already been called and false otherwise.
    */
   public static boolean isInitialized() {
     return runtime != null;
@@ -66,8 +60,8 @@ public final class Ray extends RayCall {
   /**
    * Store an object in the object store.
    *
-   * @param obj The Java object to be stored.
-   * @return A ObjectRef instance that represents the in-store object.
+   * @param obj The Java object to be stored. Returns A ObjectRef instance that represents the
+   *     in-store object.
    */
   public static <T> ObjectRef<T> put(T obj) {
     return internal().put(obj);
@@ -76,8 +70,7 @@ public final class Ray extends RayCall {
   /**
    * Get an object by `ObjectRef` from the object store.
    *
-   * @param objectRef The reference of the object to get.
-   * @return The Java object.
+   * @param objectRef The reference of the object to get. Returns The Java object.
    */
   public static <T> T get(ObjectRef<T> objectRef) {
     return internal().get(objectRef);
@@ -86,45 +79,43 @@ public final class Ray extends RayCall {
   /**
    * Get a list of objects by `ObjectRef`s from the object store.
    *
-   * @param objectList A list of object references.
-   * @return A list of Java objects.
+   * @param objectList A list of object references. Returns A list of Java objects.
    */
   public static <T> List<T> get(List<ObjectRef<T>> objectList) {
     return internal().get(objectList);
   }
 
   /**
-   * Wait for a list of RayObjects to be locally available,
-   * until specified number of objects are ready, or specified timeout has passed.
+   * Wait for a list of RayObjects to be locally available, until specified number of objects are
+   * ready, or specified timeout has passed.
    *
    * @param waitList A list of object references to wait for.
    * @param numReturns The number of objects that should be returned.
-   * @param timeoutMs The maximum time in milliseconds to wait before returning.
-   * @return Two lists, one containing locally available objects, one containing the rest.
+   * @param timeoutMs The maximum time in milliseconds to wait before returning. Returns Two lists,
+   *     one containing locally available objects, one containing the rest.
    */
-  public static <T> WaitResult<T> wait(List<ObjectRef<T>> waitList, int numReturns,
-                                       int timeoutMs) {
+  public static <T> WaitResult<T> wait(List<ObjectRef<T>> waitList, int numReturns, int timeoutMs) {
     return internal().wait(waitList, numReturns, timeoutMs);
   }
 
   /**
-   * A convenient helper method for Ray.wait. It will wait infinitely until
-   * specified number of objects are locally available.
+   * A convenient helper method for Ray.wait. It will wait infinitely until specified number of
+   * objects are locally available.
    *
    * @param waitList A list of object references to wait for.
-   * @param numReturns The number of objects that should be returned.
-   * @return Two lists, one containing locally available objects, one containing the rest.
+   * @param numReturns The number of objects that should be returned. Returns Two lists, one
+   *     containing locally available objects, one containing the rest.
    */
   public static <T> WaitResult<T> wait(List<ObjectRef<T>> waitList, int numReturns) {
     return internal().wait(waitList, numReturns, Integer.MAX_VALUE);
   }
 
   /**
-   * A convenient helper method for Ray.wait. It will wait infinitely until
-   * all objects are locally available.
+   * A convenient helper method for Ray.wait. It will wait infinitely until all objects are locally
+   * available.
    *
-   * @param waitList A list of object references to wait for.
-   * @return Two lists, one containing locally available objects, one containing the rest.
+   * @param waitList A list of object references to wait for. Returns Two lists, one containing
+   *     locally available objects, one containing the rest.
    */
   public static <T> WaitResult<T> wait(List<ObjectRef<T>> waitList) {
     return internal().wait(waitList, waitList.size(), Integer.MAX_VALUE);
@@ -132,13 +123,12 @@ public final class Ray extends RayCall {
 
   /**
    * Get a handle to a named actor of current job.
-   * <p>
-   * Gets a handle to a named actor with the given name. The actor must
-   * have been created with name specified.
    *
-   * @param name The name of the named actor.
-   * @return an ActorHandle to the actor if the actor of specified name exists or an
-   *     Optional.empty()
+   * <p>Gets a handle to a named actor with the given name. The actor must have been created with
+   * name specified.
+   *
+   * @param name The name of the named actor. Returns an ActorHandle to the actor if the actor of
+   *     specified name exists or an Optional.empty()
    */
   public static <T extends BaseActorHandle> Optional<T> getActor(String name) {
     return internal().getActor(name, false);
@@ -146,13 +136,12 @@ public final class Ray extends RayCall {
 
   /**
    * Get a handle to a global named actor.
-   * <p>
-   * Gets a handle to a global named actor with the given name. The actor must
-   * have been created with global name specified.
    *
-   * @param name The global name of the named actor.
-   * @return an ActorHandle to the actor if the actor of specified name exists or an
-   *     Optional.empty()
+   * <p>Gets a handle to a global named actor with the given name. The actor must have been created
+   * with global name specified.
+   *
+   * @param name The global name of the named actor. Returns an ActorHandle to the actor if the
+   *     actor of specified name exists or an Optional.empty()
    */
   public static <T extends BaseActorHandle> Optional<T> getGlobalActor(String name) {
     return internal().getActor(name, true);
@@ -162,7 +151,7 @@ public final class Ray extends RayCall {
    * If users want to use Ray API in their own threads, call this method to get the async context
    * and then call {@link #setAsyncContext} at the beginning of the new thread.
    *
-   * @return The async context.
+   * <p>Returns The async context.
    */
   public static Object getAsyncContext() {
     return internal().getAsyncContext();
@@ -186,8 +175,7 @@ public final class Ray extends RayCall {
    * If users want to use Ray API in their own threads, they should wrap their {@link Runnable}
    * objects with this method.
    *
-   * @param runnable The runnable to wrap.
-   * @return The wrapped runnable.
+   * @param runnable The runnable to wrap. Returns The wrapped runnable.
    */
   public static Runnable wrapRunnable(Runnable runnable) {
     return internal().wrapRunnable(runnable);
@@ -197,16 +185,13 @@ public final class Ray extends RayCall {
    * If users want to use Ray API in their own threads, they should wrap their {@link Callable}
    * objects with this method.
    *
-   * @param callable The callable to wrap.
-   * @return The wrapped callable.
+   * @param callable The callable to wrap. Returns The wrapped callable.
    */
   public static <T> Callable<T> wrapCallable(Callable<T> callable) {
     return internal().wrapCallable(callable);
   }
 
-  /**
-   * Get the underlying runtime instance.
-   */
+  /** Get the underlying runtime instance. */
   public static RayRuntime internal() {
     if (runtime == null) {
       throw new IllegalStateException(
@@ -215,59 +200,49 @@ public final class Ray extends RayCall {
     return runtime;
   }
 
-  /**
-   * Update the resource for the specified client.
-   * Set the resource for the specific node.
-   */
+  /** Update the resource for the specified client. Set the resource for the specific node. */
   public static void setResource(UniqueId nodeId, String resourceName, double capacity) {
     internal().setResource(resourceName, capacity, nodeId);
   }
 
-  /**
-   * Set the resource for local node.
-   */
+  /** Set the resource for local node. */
   public static void setResource(String resourceName, double capacity) {
     internal().setResource(resourceName, capacity, UniqueId.NIL);
   }
 
-  /**
-   * Get the runtime context.
-   */
+  /** Get the runtime context. */
   public static RuntimeContext getRuntimeContext() {
     return internal().getRuntimeContext();
   }
 
   /**
-   * Create a placement group.
-   * A placement group is used to place actors according to a specific strategy
-   * and resource constraints.
-   * It will sends a request to GCS to preallocate the specified resources, which is asynchronous.
-   * If the specified resource cannot be allocated, it will wait for the resource
-   * to be updated and rescheduled.
-   * This function only works when gcs actor manager is turned on.
+   * Create a placement group. A placement group is used to place actors according to a specific
+   * strategy and resource constraints. It will sends a request to GCS to preallocate the specified
+   * resources, which is asynchronous. If the specified resource cannot be allocated, it will wait
+   * for the resource to be updated and rescheduled. This function only works when gcs actor manager
+   * is turned on.
    *
    * @param name Name of the placement group.
    * @param bundles Pre-allocated resource list.
-   * @param strategy Actor placement strategy.
-   * @return A handle to the created placement group.
+   * @param strategy Actor placement strategy. Returns A handle to the created placement group.
    */
-  public static PlacementGroup createPlacementGroup(String name,
-      List<Map<String, Double>> bundles, PlacementStrategy strategy) {
+  public static PlacementGroup createPlacementGroup(
+      String name, List<Map<String, Double>> bundles, PlacementStrategy strategy) {
     return internal().createPlacementGroup(name, bundles, strategy);
   }
 
-  public static PlacementGroup createPlacementGroup(List<Map<String, Double>> bundles,
-      PlacementStrategy strategy) {
+  public static PlacementGroup createPlacementGroup(
+      List<Map<String, Double>> bundles, PlacementStrategy strategy) {
     return internal().createPlacementGroup(bundles, strategy);
   }
 
   /**
    * Intentionally exit the current actor.
-   * <p>
-   * This method is used to disconnect an actor and exit the worker.
    *
-   * @throws RuntimeException An exception is raised if this is a driver or this  worker is not
-   *                          an actor.
+   * <p>This method is used to disconnect an actor and exit the worker.
+   *
+   * @throws RuntimeException An exception is raised if this is a driver or this worker is not an
+   *     actor.
    */
   public static void exitActor() {
     runtime.exitActor();
@@ -275,8 +250,8 @@ public final class Ray extends RayCall {
 
   /**
    * Get a placement group by placement group Id.
-   * @param id placement group id.
-   * @return The placement group.
+   *
+   * @param id placement group id. Returns The placement group.
    */
   public static PlacementGroup getPlacementGroup(PlacementGroupId id) {
     return internal().getPlacementGroup(id);
@@ -284,15 +259,16 @@ public final class Ray extends RayCall {
 
   /**
    * Get all placement groups in this cluster.
-   * @return All placement groups.
+   *
+   * <p>Returns All placement groups.
    */
   public static List<PlacementGroup> getAllPlacementGroups() {
     return internal().getAllPlacementGroups();
   }
 
   /**
-   * Remove a placement group by id.
-   * Throw RayException if remove failed.
+   * Remove a placement group by id. Throw RayException if remove failed.
+   *
    * @param id Id of the placement group.
    */
   public static void removePlacementGroup(PlacementGroupId id) {

java/api/src/main/java/io/ray/api/WaitResult.java

@@ -3,8 +3,8 @@ package io.ray.api;
 import java.util.List;
 
 /**
- * Represents the result of a Ray.wait call. It contains 2 lists,
- * one containing the locally available objects, one containing the rest.
+ * Represents the result of a Ray.wait call. It contains 2 lists, one containing the locally
+ * available objects, one containing the rest.
  */
 public final class WaitResult<T> {
 
@@ -16,18 +16,13 @@ public final class WaitResult<T> {
     this.unready = unready;
   }
 
-  /**
-   * Get the list of ready objects.
-   */
+  /** Get the list of ready objects. */
   public List<ObjectRef<T>> getReady() {
     return ready;
   }
 
-  /**
-   * Get the list of unready objects.
-   */
+  /** Get the list of unready objects. */
   public List<ObjectRef<T>> getUnready() {
     return unready;
   }
-
 }

java/api/src/main/java/io/ray/api/call/ActorCreator.java

@@ -21,10 +21,9 @@ public class ActorCreator<A> extends BaseActorCreator<ActorCreator<A>> {
   /**
    * Set the JVM options for the Java worker that this actor is running in.
    *
-   * Note, if this is set, this actor won't share Java worker with other actors or tasks.
+   * <p>Note, if this is set, this actor won't share Java worker with other actors or tasks.
    *
-   * @param jvmOptions JVM options for the Java worker that this actor is running in.
-   * @return self
+   * @param jvmOptions JVM options for the Java worker that this actor is running in. Returns self
    * @see io.ray.api.options.ActorCreationOptions.Builder#setJvmOptions(java.lang.String)
    */
   public ActorCreator<A> setJvmOptions(String jvmOptions) {
@@ -35,10 +34,9 @@ public class ActorCreator<A> extends BaseActorCreator<ActorCreator<A>> {
   /**
    * Create a java actor remotely and return a handle to the created actor.
    *
-   * @return a handle to the created java actor.
+   * <p>Returns a handle to the created java actor.
    */
   public ActorHandle<A> remote() {
     return Ray.internal().createActor(func, args, buildOptions());
   }
-
 }

java/api/src/main/java/io/ray/api/call/ActorTaskCaller.java

@@ -25,11 +25,10 @@ public class ActorTaskCaller<R> {
    * Execute an java actor method remotely and return an object reference to the result object in
    * the object store.
    *
-   * @return an object reference to an object in the object store.
+   * <p>Returns an object reference to an object in the object store.
    */
   @SuppressWarnings("unchecked")
   public ObjectRef<R> remote() {
     return Ray.internal().callActor(actor, func, args);
   }
-
 }

java/api/src/main/java/io/ray/api/call/BaseActorCreator.java

@@ -14,13 +14,11 @@ public class BaseActorCreator<T extends BaseActorCreator> {
   protected ActorCreationOptions.Builder builder = new ActorCreationOptions.Builder();
 
   /**
-   * Set the actor name of a named actor.
-   * This named actor is only accessible from this job by this name via
-   * {@link Ray#getActor(java.lang.String)}. If you want create a named actor that is accessible
-   * from all jobs, use {@link BaseActorCreator#setGlobalName(java.lang.String)} instead.
+   * Set the actor name of a named actor. This named actor is only accessible from this job by this
+   * name via {@link Ray#getActor(java.lang.String)}. If you want create a named actor that is
+   * accessible from all jobs, use {@link BaseActorCreator#setGlobalName(java.lang.String)} instead.
    *
-   * @param name The name of the named actor.
-   * @return self
+   * @param name The name of the named actor. Returns self
    * @see io.ray.api.options.ActorCreationOptions.Builder#setName(String)
    */
   public T setName(String name) {
@@ -29,12 +27,11 @@ public class BaseActorCreator<T extends BaseActorCreator> {
   }
 
   /**
-   * Set the name of this actor. This actor will be accessible from all jobs by this name via
-   * {@link Ray#getGlobalActor(java.lang.String)}. If you want to create a named actor that is
-   * only accessible from this job, use {@link BaseActorCreator#setName(java.lang.String)} instead.
+   * Set the name of this actor. This actor will be accessible from all jobs by this name via {@link
+   * Ray#getGlobalActor(java.lang.String)}. If you want to create a named actor that is only
+   * accessible from this job, use {@link BaseActorCreator#setName(java.lang.String)} instead.
    *
-   * @param name The name of the named actor.
-   * @return self
+   * @param name The name of the named actor. Returns self
    * @see io.ray.api.options.ActorCreationOptions.Builder#setGlobalName(String)
    */
   public T setGlobalName(String name) {
@@ -43,13 +40,12 @@ public class BaseActorCreator<T extends BaseActorCreator> {
   }
 
   /**
-   * Set a custom resource requirement to reserve for the lifetime of this actor.
-   * This method can be called multiple times. If the same resource is set multiple times,
-   * the latest quantity will be used.
+   * Set a custom resource requirement to reserve for the lifetime of this actor. This method can be
+   * called multiple times. If the same resource is set multiple times, the latest quantity will be
+   * used.
    *
    * @param resourceName resource name
-   * @param resourceQuantity resource quantity
-   * @return self
+   * @param resourceQuantity resource quantity Returns self
    * @see ActorCreationOptions.Builder#setResource(java.lang.String, java.lang.Double)
    */
   public T setResource(String resourceName, Double resourceQuantity) {
@@ -58,12 +54,11 @@ public class BaseActorCreator<T extends BaseActorCreator> {
   }
 
   /**
-   * Set custom resource requirements to reserve for the lifetime of this actor.
-   * This method can be called multiple times. If the same resource is set multiple times,
-   * the latest quantity will be used.
+   * Set custom resource requirements to reserve for the lifetime of this actor. This method can be
+   * called multiple times. If the same resource is set multiple times, the latest quantity will be
+   * used.
    *
-   * @param resources requirements for multiple resources.
-   * @return self
+   * @param resources requirements for multiple resources. Returns self
    * @see BaseActorCreator#setResources(java.util.Map)
    */
   public T setResources(Map<String, Double> resources) {
@@ -76,8 +71,7 @@ public class BaseActorCreator<T extends BaseActorCreator> {
    * unexpectedly. The minimum valid value is 0 (default), which indicates that the actor doesn't
    * need to be restarted. A value of -1 indicates that an actor should be restarted indefinitely.
    *
-   * @param maxRestarts max number of actor restarts
-   * @return self
+   * @param maxRestarts max number of actor restarts Returns self
    * @see ActorCreationOptions.Builder#setMaxRestarts(int)
    */
   public T setMaxRestarts(int maxRestarts) {
@@ -87,12 +81,11 @@ public class BaseActorCreator<T extends BaseActorCreator> {
 
   /**
    * Set the max number of concurrent calls to allow for this actor.
-   * <p>
-   * The max concurrency defaults to 1 for threaded execution.
-   * Note that the execution order is not guaranteed when {@code max_concurrency > 1}.
    *
-   * @param maxConcurrency The max number of concurrent calls to allow for this actor.
-   * @return self
+   * <p>The max concurrency defaults to 1 for threaded execution. Note that the execution order is
+   * not guaranteed when {@code max_concurrency > 1}.
+   *
+   * @param maxConcurrency The max number of concurrent calls to allow for this actor. Returns self
    * @see ActorCreationOptions.Builder#setMaxConcurrency(int)
    */
   public T setMaxConcurrency(int maxConcurrency) {
@@ -104,8 +97,7 @@ public class BaseActorCreator<T extends BaseActorCreator> {
    * Set the placement group to place this actor in.
    *
    * @param group The placement group of the actor.
-   * @param bundleIndex The index of the bundle to place this actor in.
-   * @return self
+   * @param bundleIndex The index of the bundle to place this actor in. Returns self
    * @see ActorCreationOptions.Builder#setPlacementGroup(PlacementGroup, int)
    */
   public T setPlacementGroup(PlacementGroup group, int bundleIndex) {
@@ -121,5 +113,4 @@ public class BaseActorCreator<T extends BaseActorCreator> {
   protected ActorCreationOptions buildOptions() {
     return builder.build();
   }
-
 }

java/api/src/main/java/io/ray/api/call/BaseTaskCaller.java

@@ -14,8 +14,7 @@ public class BaseTaskCaller<T extends BaseTaskCaller<T>> {
   /**
    * Set a name for this task.
    *
-   * @param name task name
-   * @return self
+   * @param name task name Returns self
    * @see CallOptions.Builder#setName(java.lang.String)
    */
   public T setName(String name) {
@@ -28,8 +27,7 @@ public class BaseTaskCaller<T extends BaseTaskCaller<T>> {
    * times. If the same resource is set multiple times, the latest quantity will be used.
    *
    * @param name resource name
-   * @param value resource capacity
-   * @return self
+   * @param value resource capacity Returns self
    * @see CallOptions.Builder#setResource(java.lang.String, java.lang.Double)
    */
   public T setResource(String name, Double value) {
@@ -41,8 +39,7 @@ public class BaseTaskCaller<T extends BaseTaskCaller<T>> {
    * Set custom requirements for multiple resources. This method can be called multiple times. If
    * the same resource is set multiple times, the latest quantity will be used.
    *
-   * @param resources requirements for multiple resources.
-   * @return self
+   * @param resources requirements for multiple resources. Returns self
    * @see CallOptions.Builder#setResources(java.util.Map)
    */
   public T setResources(Map<String, Double> resources) {

java/api/src/main/java/io/ray/api/call/PyActorCreator.java

@@ -4,9 +4,7 @@ import io.ray.api.PyActorHandle;
 import io.ray.api.Ray;
 import io.ray.api.function.PyActorClass;
 
-/**
- * A helper to create python actor.
- */
+/** A helper to create python actor. */
 public class PyActorCreator extends BaseActorCreator<PyActorCreator> {
   private final PyActorClass pyActorClass;
   private final Object[] args;
@@ -19,7 +17,7 @@ public class PyActorCreator extends BaseActorCreator<PyActorCreator> {
   /**
    * Create a python actor remotely and return a handle to the created actor.
    *
-   * @return a handle to the created python actor.
+   * <p>Returns a handle to the created python actor.
    */
   public PyActorHandle remote() {
     return Ray.internal().createActor(pyActorClass, args, buildOptions());

java/api/src/main/java/io/ray/api/call/PyActorTaskCaller.java

@@ -25,11 +25,10 @@ public class PyActorTaskCaller<R> {
    * Execute a python actor method remotely and return an object reference to the result object in
    * the object store.
    *
-   * @return an object reference to an object in the object store.
+   * <p>Returns an object reference to an object in the object store.
    */
   @SuppressWarnings("unchecked")
   public ObjectRef<R> remote() {
     return Ray.internal().callActor(actor, method, args);
   }
-
 }

java/api/src/main/java/io/ray/api/call/PyTaskCaller.java

@@ -22,11 +22,10 @@ public class PyTaskCaller<R> extends BaseTaskCaller<PyTaskCaller<R>> {
    * Execute a python function remotely and return an object reference to the result object in the
    * object store.
    *
-   * @return an object reference to an object in the object store.
+   * <p>Returns an object reference to an object in the object store.
    */
   @SuppressWarnings("unchecked")
   public ObjectRef<R> remote() {
     return Ray.internal().call(func, args, buildOptions());
   }
-
 }

java/api/src/main/java/io/ray/api/call/TaskCaller.java

@@ -22,7 +22,7 @@ public class TaskCaller<R> extends BaseTaskCaller<TaskCaller<R>> {
    * Execute a java function remotely and return an object reference to the result object in the
    * object store.
    *
-   * @return an object reference to an object in the object store.
+   * <p>Returns an object reference to an object in the object store.
    */
   @SuppressWarnings("unchecked")
   public ObjectRef<R> remote() {

java/api/src/main/java/io/ray/api/call/VoidActorTaskCaller.java

@@ -4,9 +4,7 @@ import io.ray.api.ActorHandle;
 import io.ray.api.Ray;
 import io.ray.api.function.RayFuncVoid;
 
-/**
- * A helper to call java actor method which doesn't have a return value.
- */
+/** A helper to call java actor method which doesn't have a return value. */
 public class VoidActorTaskCaller {
   private final ActorHandle actor;
   private final RayFuncVoid func;
@@ -18,11 +16,8 @@ public class VoidActorTaskCaller {
     this.args = args;
   }
 
-  /**
-   * Execute a function remotely.
-   */
+  /** Execute a function remotely. */
   public void remote() {
     Ray.internal().callActor(actor, func, args);
   }
-
 }

java/api/src/main/java/io/ray/api/call/VoidTaskCaller.java

@@ -3,9 +3,7 @@ package io.ray.api.call;
 import io.ray.api.Ray;
 import io.ray.api.function.RayFuncVoid;
 
-/**
- * A helper to call java remote function which doesn't have a return value.
- */
+/** A helper to call java remote function which doesn't have a return value. */
 public class VoidTaskCaller extends BaseTaskCaller<VoidTaskCaller> {
   private final RayFuncVoid func;
   private final Object[] args;
@@ -15,11 +13,8 @@ public class VoidTaskCaller extends BaseTaskCaller<VoidTaskCaller> {
     this.args = args;
   }
 
-  /**
-   * Execute a function remotely.
-   */
+  /** Execute a function remotely. */
   public void remote() {
     Ray.internal().call(func, args, buildOptions());
   }
-
 }

java/api/src/main/java/io/ray/api/function/PyActorClass.java

@@ -38,11 +38,9 @@ public class PyActorClass {
    * Create a python actor class.
    *
    * @param moduleName The full module name of this actor class
-   * @param className The name of this actor class
-   * @return a python actor class
+   * @param className The name of this actor class Returns a python actor class
    */
   public static PyActorClass of(String moduleName, String className) {
     return new PyActorClass(moduleName, className);
   }
-
 }

java/api/src/main/java/io/ray/api/function/PyActorMethod.java

@@ -2,9 +2,9 @@ package io.ray.api.function;
 
 /**
  * A class that represents a method of a Python actor.
- * <p>
- * Note, information about the actor will be inferred from the actor handle,
- * so it's not specified in this class.
+ *
+ * <p>Note, information about the actor will be inferred from the actor handle, so it's not
+ * specified in this class.
  *
  * <pre>
  * there is a Python actor class A.
@@ -43,8 +43,7 @@ public class PyActorMethod<R> {
   /**
    * Create a python actor method.
    *
-   * @param methodName The name of this actor method
-   * @return a python actor method.
+   * @param methodName The name of this actor method Returns a python actor method.
    */
   public static PyActorMethod<Object> of(String methodName) {
     return of(methodName, Object.class);
@@ -55,11 +54,9 @@ public class PyActorMethod<R> {
    *
    * @param methodName The name of this actor method
    * @param returnType Class of the return value of this actor method
-   * @param <R> The type of the return value of this actor method
-   * @return a python actor method.
+   * @param <R> The type of the return value of this actor method Returns a python actor method.
    */
   public static <R> PyActorMethod<R> of(String methodName, Class<R> returnType) {
     return new PyActorMethod<>(methodName, returnType);
   }
-
 }

java/api/src/main/java/io/ray/api/function/PyFunction.java

@@ -49,11 +49,9 @@ public class PyFunction<R> {
    * Create a python function.
    *
    * @param moduleName The full module name of this function
-   * @param functionName The name of this function
-   * @return a python function.
+   * @param functionName The name of this function Returns a python function.
    */
-  public static PyFunction<Object> of(
-      String moduleName, String functionName) {
+  public static PyFunction<Object> of(String moduleName, String functionName) {
     return of(moduleName, functionName, Object.class);
   }
 
@@ -63,12 +61,9 @@ public class PyFunction<R> {
    * @param moduleName The full module name of this function
    * @param functionName The name of this function
    * @param returnType Class of the return value of this function
-   * @param <R> Type of the return value of this function
-   * @return a python function.
+   * @param <R> Type of the return value of this function Returns a python function.
    */
-  public static <R> PyFunction<R> of(
-      String moduleName, String functionName, Class<R> returnType) {
+  public static <R> PyFunction<R> of(String moduleName, String functionName, Class<R> returnType) {
     return new PyFunction<>(moduleName, functionName, returnType);
   }
-
 }

java/api/src/main/java/io/ray/api/function/RayFunc.java

@@ -2,8 +2,5 @@ package io.ray.api.function;
 
 import java.io.Serializable;
 
-/**
- * Base interface of all Ray remote java functions.
- */
-public interface RayFunc extends Serializable {
-}
+/** Base interface of all Ray remote java functions. */
+public interface RayFunc extends Serializable {}

java/api/src/main/java/io/ray/api/function/RayFunc0.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 0 parameter.
- */
+/** Functional interface for a remote function that has 0 parameter. */
 @FunctionalInterface
 public interface RayFunc0<R> extends RayFuncR<R> {
 

java/api/src/main/java/io/ray/api/function/RayFunc1.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 1 parameter.
- */
+/** Functional interface for a remote function that has 1 parameter. */
 @FunctionalInterface
 public interface RayFunc1<T0, R> extends RayFuncR<R> {
 

java/api/src/main/java/io/ray/api/function/RayFunc2.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 2 parameters.
- */
+/** Functional interface for a remote function that has 2 parameters. */
 @FunctionalInterface
 public interface RayFunc2<T0, T1, R> extends RayFuncR<R> {
 

java/api/src/main/java/io/ray/api/function/RayFunc3.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 3 parameters.
- */
+/** Functional interface for a remote function that has 3 parameters. */
 @FunctionalInterface
 public interface RayFunc3<T0, T1, T2, R> extends RayFuncR<R> {
 

java/api/src/main/java/io/ray/api/function/RayFunc4.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 4 parameters.
- */
+/** Functional interface for a remote function that has 4 parameters. */
 @FunctionalInterface
 public interface RayFunc4<T0, T1, T2, T3, R> extends RayFuncR<R> {
 

java/api/src/main/java/io/ray/api/function/RayFunc5.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 5 parameters.
- */
+/** Functional interface for a remote function that has 5 parameters. */
 @FunctionalInterface
 public interface RayFunc5<T0, T1, T2, T3, T4, R> extends RayFuncR<R> {
 

java/api/src/main/java/io/ray/api/function/RayFunc6.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 6 parameters.
- */
+/** Functional interface for a remote function that has 6 parameters. */
 @FunctionalInterface
 public interface RayFunc6<T0, T1, T2, T3, T4, T5, R> extends RayFuncR<R> {
 

java/api/src/main/java/io/ray/api/function/RayFuncR.java

@@ -1,10 +1,8 @@
 package io.ray.api.function;
 
 /**
- * Interface of all Ray remote functions which have a return value
+ * Interface of all Ray remote functions which have a return value.
  *
  * @param <R> Type of function return value
  */
-public interface RayFuncR<R> extends RayFunc {
-
-}
+public interface RayFuncR<R> extends RayFunc {}

java/api/src/main/java/io/ray/api/function/RayFuncVoid.java

@@ -1,8 +1,4 @@
 package io.ray.api.function;
 
-/**
- * Interface of all `RayFuncVoidX` classes.
- */
-public interface RayFuncVoid extends RayFunc {
-
-}
+/** Interface of all `RayFuncVoidX` classes. */
+public interface RayFuncVoid extends RayFunc {}

java/api/src/main/java/io/ray/api/function/RayFuncVoid0.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 0 parameter.
- */
+/** Functional interface for a remote function that has 0 parameter. */
 @FunctionalInterface
 public interface RayFuncVoid0 extends RayFuncVoid {
 

java/api/src/main/java/io/ray/api/function/RayFuncVoid1.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 1 parameter.
- */
+/** Functional interface for a remote function that has 1 parameter. */
 @FunctionalInterface
 public interface RayFuncVoid1<T0> extends RayFuncVoid {
 

java/api/src/main/java/io/ray/api/function/RayFuncVoid2.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 2 parameters.
- */
+/** Functional interface for a remote function that has 2 parameters. */
 @FunctionalInterface
 public interface RayFuncVoid2<T0, T1> extends RayFuncVoid {
 

java/api/src/main/java/io/ray/api/function/RayFuncVoid3.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 3 parameters.
- */
+/** Functional interface for a remote function that has 3 parameters. */
 @FunctionalInterface
 public interface RayFuncVoid3<T0, T1, T2> extends RayFuncVoid {
 

java/api/src/main/java/io/ray/api/function/RayFuncVoid4.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 4 parameters.
- */
+/** Functional interface for a remote function that has 4 parameters. */
 @FunctionalInterface
 public interface RayFuncVoid4<T0, T1, T2, T3> extends RayFuncVoid {
 

java/api/src/main/java/io/ray/api/function/RayFuncVoid5.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 5 parameters.
- */
+/** Functional interface for a remote function that has 5 parameters. */
 @FunctionalInterface
 public interface RayFuncVoid5<T0, T1, T2, T3, T4> extends RayFuncVoid {
 

java/api/src/main/java/io/ray/api/function/RayFuncVoid6.java

@@ -2,9 +2,7 @@
 
 package io.ray.api.function;
 
-/**
- * Functional interface for a remote function that has 6 parameters.
- */
+/** Functional interface for a remote function that has 6 parameters. */
 @FunctionalInterface
 public interface RayFuncVoid6<T0, T1, T2, T3, T4, T5> extends RayFuncVoid {
 

java/api/src/main/java/io/ray/api/id/ActorId.java

@@ -25,18 +25,14 @@ public class ActorId extends BaseId implements Serializable {
     return new ActorId(bytes);
   }
 
-  /**
-   * Generate a nil ActorId.
-   */
+  /** Generate a nil ActorId. */
   private static ActorId nil() {
     byte[] b = new byte[LENGTH];
     Arrays.fill(b, (byte) 0xFF);
     return new ActorId(b);
   }
 
-  /**
-   * Generate an ActorId with random value. Used for local mode and test only.
-   */
+  /** Generate an ActorId with random value. Used for local mode and test only. */
   public static ActorId fromRandom() {
     byte[] b = new byte[LENGTH];
     new Random().nextBytes(b);

java/api/src/main/java/io/ray/api/id/BaseId.java

@@ -11,34 +11,30 @@ public abstract class BaseId implements Serializable {
   private int hashCodeCache = 0;
   private Boolean isNilCache = null;
 
-  /**
-   * Create a BaseId instance according to the input byte array.
-   */
+  /** Create a BaseId instance according to the input byte array. */
   protected BaseId(byte[] id) {
     if (id.length != size()) {
-      throw new IllegalArgumentException("Failed to construct BaseId, expect " + size()
-              + " bytes, but got " + id.length + " bytes.");
+      throw new IllegalArgumentException(
+          "Failed to construct BaseId, expect "
+              + size()
+              + " bytes, but got "
+              + id.length
+              + " bytes.");
     }
     this.id = id;
   }
 
-  /**
-   * Get the byte data of this id.
-   */
+  /** Get the byte data of this id. */
   public byte[] getBytes() {
     return id;
   }
 
-  /**
-   * Convert the byte data to a ByteBuffer.
-   */
+  /** Convert the byte data to a ByteBuffer. */
   public ByteBuffer toByteBuffer() {
     return ByteBuffer.wrap(id);
   }
 
-  /**
-   * @return True if this id is nil.
-   */
+  /** Returns true if this id is nil. */
   public boolean isNil() {
     if (isNilCache == null) {
       boolean localIsNil = true;
@@ -55,7 +51,8 @@ public abstract class BaseId implements Serializable {
 
   /**
    * Derived class should implement this function.
-   * @return The length of this id in bytes.
+   *
+   * <p>Returns The length of this id in bytes.
    */
   public abstract int size();
 
@@ -96,5 +93,4 @@ public abstract class BaseId implements Serializable {
     bb.get(id);
     return id;
   }
-
 }

java/api/src/main/java/io/ray/api/id/JobId.java

@@ -5,32 +5,24 @@ import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
 import java.util.Arrays;
 
-/**
- * Represents the id of a Ray job.
- */
+/** Represents the id of a Ray job. */
 public class JobId extends BaseId implements Serializable {
 
   public static final int LENGTH = 4;
 
   public static final JobId NIL = genNil();
 
-  /**
-   * Create a JobID instance according to the given bytes.
-   */
+  /** Create a JobID instance according to the given bytes. */
   private JobId(byte[] id) {
     super(id);
   }
 
-  /**
-   * Create a JobId from a given hex string.
-   */
+  /** Create a JobId from a given hex string. */
   public static JobId fromHexString(String hex) {
     return new JobId(hexString2Bytes(hex));
   }
 
-  /**
-   * Creates a JobId from the given ByteBuffer.
-   */
+  /** Creates a JobId from the given ByteBuffer. */
   public static JobId fromByteBuffer(ByteBuffer bb) {
     return new JobId(byteBuffer2Bytes(bb));
   }
@@ -49,9 +41,7 @@ public class JobId extends BaseId implements Serializable {
     return JobId.fromByteBuffer(wbb);
   }
 
-  /**
-   * Generate a nil JobId.
-   */
+  /** Generate a nil JobId. */
   private static JobId genNil() {
     byte[] b = new byte[LENGTH];
     Arrays.fill(b, (byte) 0xFF);

java/api/src/main/java/io/ray/api/id/ObjectId.java

@@ -5,23 +5,17 @@ import java.nio.ByteBuffer;
 import java.util.Arrays;
 import java.util.Random;
 
-/**
- * Represents the id of a Ray object.
- */
+/** Represents the id of a Ray object. */
 public class ObjectId extends BaseId implements Serializable {
 
   public static final int LENGTH = 28;
 
-  /**
-   * Create an ObjectId from a ByteBuffer.
-   */
+  /** Create an ObjectId from a ByteBuffer. */
   public static ObjectId fromByteBuffer(ByteBuffer bb) {
     return new ObjectId(byteBuffer2Bytes(bb));
   }
 
-  /**
-   * Generate an ObjectId with random value.
-   */
+  /** Generate an ObjectId with random value. */
   public static ObjectId fromRandom() {
     // This is tightly coupled with ObjectID definition in C++. If that changes,
     // this must be changed as well.
@@ -41,5 +35,4 @@ public class ObjectId extends BaseId implements Serializable {
   public int size() {
     return LENGTH;
   }
-
 }

java/api/src/main/java/io/ray/api/id/PlacementGroupId.java

@@ -5,9 +5,7 @@ import java.nio.ByteBuffer;
 import java.util.Arrays;
 import java.util.Random;
 
-/**
- * Represents the id of a placement group.
- */
+/** Represents the id of a placement group. */
 public class PlacementGroupId extends BaseId implements Serializable {
 
   public static final int LENGTH = 16;
@@ -18,32 +16,24 @@ public class PlacementGroupId extends BaseId implements Serializable {
     super(id);
   }
 
-  /**
-   * Creates a PlacementGroupId from the given ByteBuffer.
-   */
+  /** Creates a PlacementGroupId from the given ByteBuffer. */
   public static PlacementGroupId fromByteBuffer(ByteBuffer bb) {
     return new PlacementGroupId(byteBuffer2Bytes(bb));
   }
 
-  /**
-   * Create a PlacementGroupId instance according to the given bytes.
-   */
+  /** Create a PlacementGroupId instance according to the given bytes. */
   public static PlacementGroupId fromBytes(byte[] bytes) {
     return new PlacementGroupId(bytes);
   }
 
-  /**
-   * Generate a nil PlacementGroupId.
-   */
+  /** Generate a nil PlacementGroupId. */
   private static PlacementGroupId nil() {
     byte[] b = new byte[LENGTH];
     Arrays.fill(b, (byte) 0xFF);
     return new PlacementGroupId(b);
   }
 
-  /**
-   * Generate an PlacementGroupId with random value. Used for local mode and test only.
-   */
+  /** Generate an PlacementGroupId with random value. Used for local mode and test only. */
   public static PlacementGroupId fromRandom() {
     byte[] b = new byte[LENGTH];
     new Random().nextBytes(b);

java/api/src/main/java/io/ray/api/id/TaskId.java

@@ -4,9 +4,7 @@ import java.io.Serializable;
 import java.nio.ByteBuffer;
 import java.util.Arrays;
 
-/**
- * Represents the id of a Ray task.
- */
+/** Represents the id of a Ray task. */
 public class TaskId extends BaseId implements Serializable {
 
   public static final int UNIQUE_BYTES_LENGTH = 8;
@@ -15,30 +13,22 @@ public class TaskId extends BaseId implements Serializable {
 
   public static final TaskId NIL = genNil();
 
-  /**
-   * Create a TaskId from a hex string.
-   */
+  /** Create a TaskId from a hex string. */
   public static TaskId fromHexString(String hex) {
     return new TaskId(hexString2Bytes(hex));
   }
 
-  /**
-   * Creates a TaskId from a ByteBuffer.
-   */
+  /** Creates a TaskId from a ByteBuffer. */
   public static TaskId fromByteBuffer(ByteBuffer bb) {
     return new TaskId(byteBuffer2Bytes(bb));
   }
 
-  /**
-   * Creates a TaskId from given bytes.
-   */
+  /** Creates a TaskId from given bytes. */
   public static TaskId fromBytes(byte[] bytes) {
     return new TaskId(bytes);
   }
 
-  /**
-   * Generate a nil TaskId.
-   */
+  /** Generate a nil TaskId. */
   private static TaskId genNil() {
     byte[] b = new byte[LENGTH];
     Arrays.fill(b, (byte) 0xFF);

java/api/src/main/java/io/ray/api/id/UniqueId.java

@@ -5,41 +5,30 @@ import java.nio.ByteBuffer;
 import java.util.Arrays;
 import java.util.Random;
 
-/**
- * Represents a unique id of all Ray concepts, including
- * workers, actors, checkpoints, etc.
- */
+/** Represents a unique id of all Ray concepts, including workers, actors, checkpoints, etc. */
 public class UniqueId extends BaseId implements Serializable {
 
   public static final int LENGTH = 28;
   public static final UniqueId NIL = genNil();
 
-  /**
-   * Create a UniqueId from a hex string.
-   */
+  /** Create a UniqueId from a hex string. */
   public static UniqueId fromHexString(String hex) {
     return new UniqueId(hexString2Bytes(hex));
   }
 
-  /**
-   * Creates a UniqueId from a ByteBuffer.
-   */
+  /** Creates a UniqueId from a ByteBuffer. */
   public static UniqueId fromByteBuffer(ByteBuffer bb) {
     return new UniqueId(byteBuffer2Bytes(bb));
   }
 
-  /**
-   * Generate a nil UniqueId.
-   */
+  /** Generate a nil UniqueId. */
   private static UniqueId genNil() {
     byte[] b = new byte[LENGTH];
     Arrays.fill(b, (byte) 0xFF);
     return new UniqueId(b);
   }
 
-  /**
-   * Generate an UniqueId with random value.
-   */
+  /** Generate an UniqueId with random value. */
   public static UniqueId randomId() {
     byte[] b = new byte[LENGTH];
     new Random().nextBytes(b);

java/api/src/main/java/io/ray/api/options/ActorCreationOptions.java

@@ -5,9 +5,7 @@ import io.ray.api.placementgroup.PlacementGroup;
 import java.util.HashMap;
 import java.util.Map;
 
-/**
- * The options for creating actor.
- */
+/** The options for creating actor. */
 public class ActorCreationOptions extends BaseTaskOptions {
   public final boolean global;
   public final String name;
@@ -17,9 +15,15 @@ public class ActorCreationOptions extends BaseTaskOptions {
   public final PlacementGroup group;
   public final int bundleIndex;
 
-  private ActorCreationOptions(boolean global, String name, Map<String, Double> resources,
-                               int maxRestarts, String jvmOptions, int maxConcurrency,
-                               PlacementGroup group, int bundleIndex) {
+  private ActorCreationOptions(
+      boolean global,
+      String name,
+      Map<String, Double> resources,
+      int maxRestarts,
+      String jvmOptions,
+      int maxConcurrency,
+      PlacementGroup group,
+      int bundleIndex) {
     super(resources);
     this.global = global;
     this.name = name;
@@ -30,9 +34,7 @@ public class ActorCreationOptions extends BaseTaskOptions {
     this.bundleIndex = bundleIndex;
   }
 
-  /**
-   * The inner class for building ActorCreationOptions.
-   */
+  /** The inner class for building ActorCreationOptions. */
   public static class Builder {
     private boolean global;
     private String name;
@@ -44,13 +46,11 @@ public class ActorCreationOptions extends BaseTaskOptions {
     private int bundleIndex;
 
     /**
-     * Set the actor name of a named actor.
-     * This named actor is only accessible from this job by this name via
-     * {@link Ray#getActor(java.lang.String)}. If you want create a named actor that is accessible
-     * from all jobs, use {@link Builder#setGlobalName(java.lang.String)} instead.
+     * Set the actor name of a named actor. This named actor is only accessible from this job by
+     * this name via {@link Ray#getActor(java.lang.String)}. If you want create a named actor that
+     * is accessible from all jobs, use {@link Builder#setGlobalName(java.lang.String)} instead.
      *
-     * @param name The name of the named actor.
-     * @return self
+     * @param name The name of the named actor. Returns self
      */
     public Builder setName(String name) {
       this.name = name;
@@ -63,8 +63,7 @@ public class ActorCreationOptions extends BaseTaskOptions {
      * {@link Ray#getGlobalActor(java.lang.String)}. If you want to create a named actor that is
      * only accessible from this job, use {@link Builder#setName(java.lang.String)} instead.
      *
-     * @param name The name of the named actor.
-     * @return self
+     * @param name The name of the named actor. Returns self
      */
     public Builder setGlobalName(String name) {
       this.name = name;
@@ -73,13 +72,12 @@ public class ActorCreationOptions extends BaseTaskOptions {
     }
 
     /**
-     * Set a custom resource requirement to reserve for the lifetime of this actor.
-     * This method can be called multiple times. If the same resource is set multiple times,
-     * the latest quantity will be used.
+     * Set a custom resource requirement to reserve for the lifetime of this actor. This method can
+     * be called multiple times. If the same resource is set multiple times, the latest quantity
+     * will be used.
      *
      * @param resourceName resource name
-     * @param resourceQuantity resource quantity
-     * @return self
+     * @param resourceQuantity resource quantity Returns self
      */
     public Builder setResource(String resourceName, Double resourceQuantity) {
       this.resources.put(resourceName, resourceQuantity);
@@ -87,12 +85,11 @@ public class ActorCreationOptions extends BaseTaskOptions {
     }
 
     /**
-     * Set custom resource requirements to reserve for the lifetime of this actor.
-     * This method can be called multiple times. If the same resource is set multiple times,
-     * the latest quantity will be used.
+     * Set custom resource requirements to reserve for the lifetime of this actor. This method can
+     * be called multiple times. If the same resource is set multiple times, the latest quantity
+     * will be used.
      *
-     * @param resources requirements for multiple resources.
-     * @return self
+     * @param resources requirements for multiple resources. Returns self
      */
     public Builder setResources(Map<String, Double> resources) {
       this.resources.putAll(resources);
@@ -104,8 +101,7 @@ public class ActorCreationOptions extends BaseTaskOptions {
      * unexpectedly. The minimum valid value is 0 (default), which indicates that the actor doesn't
      * need to be restarted. A value of -1 indicates that an actor should be restarted indefinitely.
      *
-     * @param maxRestarts max number of actor restarts
-     * @return self
+     * @param maxRestarts max number of actor restarts Returns self
      */
     public Builder setMaxRestarts(int maxRestarts) {
       this.maxRestarts = maxRestarts;
@@ -114,11 +110,10 @@ public class ActorCreationOptions extends BaseTaskOptions {
 
     /**
      * Set the JVM options for the Java worker that this actor is running in.
-     * <p>
-     * Note, if this is set, this actor won't share Java worker with other actors or tasks.
      *
-     * @param jvmOptions JVM options for the Java worker that this actor is running in.
-     * @return self
+     * <p>Note, if this is set, this actor won't share Java worker with other actors or tasks.
+     *
+     * @param jvmOptions JVM options for the Java worker that this actor is running in. Returns self
      */
     public Builder setJvmOptions(String jvmOptions) {
       this.jvmOptions = jvmOptions;
@@ -127,12 +122,12 @@ public class ActorCreationOptions extends BaseTaskOptions {
 
     /**
      * Set the max number of concurrent calls to allow for this actor.
-     * <p>
-     * The max concurrency defaults to 1 for threaded execution.
-     * Note that the execution order is not guaranteed when {@code max_concurrency > 1}.
      *
-     * @param maxConcurrency The max number of concurrent calls to allow for this actor.
-     * @return self
+     * <p>The max concurrency defaults to 1 for threaded execution. Note that the execution order is
+     * not guaranteed when {@code max_concurrency > 1}.
+     *
+     * @param maxConcurrency The max number of concurrent calls to allow for this actor. Returns
+     *     self
      */
     public Builder setMaxConcurrency(int maxConcurrency) {
       if (maxConcurrency <= 0) {
@@ -147,8 +142,7 @@ public class ActorCreationOptions extends BaseTaskOptions {
      * Set the placement group to place this actor in.
      *
      * @param group The placement group of the actor.
-     * @param bundleIndex The index of the bundle to place this actor in.
-     * @return self
+     * @param bundleIndex The index of the bundle to place this actor in. Returns self
      */
     public Builder setPlacementGroup(PlacementGroup group, int bundleIndex) {
       this.group = group;
@@ -161,5 +155,4 @@ public class ActorCreationOptions extends BaseTaskOptions {
           global, name, resources, maxRestarts, jvmOptions, maxConcurrency, group, bundleIndex);
     }
   }
-
 }

java/api/src/main/java/io/ray/api/options/BaseTaskOptions.java

@@ -4,9 +4,7 @@ import java.io.Serializable;
 import java.util.HashMap;
 import java.util.Map;
 
-/**
- * The options class for RayCall or ActorCreation.
- */
+/** The options class for RayCall or ActorCreation. */
 public abstract class BaseTaskOptions implements Serializable {
 
   public final Map<String, Double> resources;
@@ -18,19 +16,22 @@ public abstract class BaseTaskOptions implements Serializable {
   public BaseTaskOptions(Map<String, Double> resources) {
     for (Map.Entry<String, Double> entry : resources.entrySet()) {
       if (entry.getValue() == null || entry.getValue().compareTo(0.0) <= 0) {
-        throw new IllegalArgumentException(String.format("Resource values should be "
-            + "positive. Specified resource: %s = %s.", entry.getKey(), entry.getValue()));
+        throw new IllegalArgumentException(
+            String.format(
+                "Resource values should be " + "positive. Specified resource: %s = %s.",
+                entry.getKey(), entry.getValue()));
       }
       // Note: A resource value should be an integer if it is greater than 1.0.
       // e.g. 3.0 is a valid resource value, but 3.5 is not.
       if (entry.getValue().compareTo(1.0) >= 0
           && entry.getValue().compareTo(Math.floor(entry.getValue())) != 0) {
-        throw new IllegalArgumentException(String.format("A resource value should be "
+        throw new IllegalArgumentException(
+            String.format(
+                "A resource value should be "
                     + "an integer if it is greater than 1.0. Specified resource: %s = %s.",
                 entry.getKey(), entry.getValue()));
       }
     }
     this.resources = resources;
   }
-
 }

java/api/src/main/java/io/ray/api/options/CallOptions.java

@@ -22,8 +22,7 @@ public class CallOptions extends BaseTaskOptions {
     /**
      * Set a name for this task.
      *
-     * @param name task name
-     * @return self
+     * @param name task name Returns self
      */
     public Builder setName(String name) {
       this.name = name;
@@ -35,8 +34,7 @@ public class CallOptions extends BaseTaskOptions {
      * multiple times. If the same resource is set multiple times, the latest quantity will be used.
      *
      * @param name resource name
-     * @param value resource capacity
-     * @return self
+     * @param value resource capacity Returns self
      */
     public Builder setResource(String name, Double value) {
       this.resources.put(name, value);
@@ -47,8 +45,7 @@ public class CallOptions extends BaseTaskOptions {
      * Set custom requirements for multiple resources. This method can be called multiple times. If
      * the same resource is set multiple times, the latest quantity will be used.
      *
-     * @param resources requirements for multiple resources.
-     * @return self
+     * @param resources requirements for multiple resources. Returns self
      */
     public Builder setResources(Map<String, Double> resources) {
       this.resources.putAll(resources);

java/api/src/main/java/io/ray/api/placementgroup/PlacementGroup.java

@@ -1,10 +1,9 @@
 package io.ray.api.placementgroup;
 
 /**
- * A placement group is used to place interdependent actors according to a specific strategy
- * {@link PlacementStrategy}.
- * When a placement group is created, the corresponding actor slots and resources are preallocated.
- * A placement group consists of one or more bundles plus a specific placement strategy.
+ * A placement group is used to place interdependent actors according to a specific strategy {@link
+ * PlacementStrategy}. When a placement group is created, the corresponding actor slots and
+ * resources are preallocated. A placement group consists of one or more bundles plus a specific
+ * placement strategy.
  */
-public interface PlacementGroup {
-}
+public interface PlacementGroup {}

java/api/src/main/java/io/ray/api/placementgroup/PlacementGroupState.java

@@ -1,33 +1,21 @@
 package io.ray.api.placementgroup;
 
-/**
- * State of placement group.
- */
+/** State of placement group. */
 public enum PlacementGroupState {
 
-  /**
-   * Wait for resource to schedule.
-   */
+  /** Wait for resource to schedule. */
   PENDING(0),
 
-  /**
-   * The placement group has created on some node.
-   */
+  /** The placement group has created on some node. */
   CREATED(1),
 
-  /**
-   * The placement group has removed.
-   */
+  /** The placement group has removed. */
   REMOVED(2),
 
-  /**
-   * The placement group is rescheduling.
-   */
+  /** The placement group is rescheduling. */
   RESCHEDULING(3),
 
-  /**
-   * Unrecognized state.
-   */
+  /** Unrecognized state. */
   UNRECOGNIZED(-1);
 
   private int value = 0;

java/api/src/main/java/io/ray/api/placementgroup/PlacementStrategy.java

@@ -1,33 +1,23 @@
 package io.ray.api.placementgroup;
 
-/**
- * The actor placement strategy.
- */
+/** The actor placement strategy. */
 public enum PlacementStrategy {
-  /**
-   * Packs Bundles close together inside nodes as tight as possible.
-   */
+  /** Packs Bundles close together inside nodes as tight as possible. */
   PACK(0),
 
-  /**
-   * Places Bundles across distinct nodes as even as possible.
-   */
+  /** Places Bundles across distinct nodes as even as possible. */
   SPREAD(1),
 
-  /**
-   * Packs Bundles into one node. The group is not allowed to span multiple nodes.
-   */
+  /** Packs Bundles into one node. The group is not allowed to span multiple nodes. */
   STRICT_PACK(2),
 
   /**
-   * Places Bundles across distinct nodes.
-   * The group is not allowed to deploy more than one bundle on a node.
+   * Places Bundles across distinct nodes. The group is not allowed to deploy more than one bundle
+   * on a node.
    */
   STRICT_SPREAD(3),
 
-  /**
-   * Unrecognized strategy.
-   */
+  /** Unrecognized strategy. */
   UNRECOGNIZED(-1);
 
   private int value = 0;

java/api/src/main/java/io/ray/api/runtime/RayRuntime.java

@@ -22,37 +22,31 @@ import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.Callable;
 
-/**
- * Base interface of a Ray runtime.
- */
+/** Base interface of a Ray runtime. */
 public interface RayRuntime {
 
-  /**
-   * Shutdown the runtime.
-   */
+  /** Shutdown the runtime. */
   void shutdown();
 
   /**
    * Store an object in the object store.
    *
-   * @param obj The Java object to be stored.
-   * @return A ObjectRef instance that represents the in-store object.
+   * @param obj The Java object to be stored. Returns A ObjectRef instance that represents the
+   *     in-store object.
    */
   <T> ObjectRef<T> put(T obj);
 
   /**
    * Get an object from the object store.
    *
-   * @param objectRef The reference of the object to get.
-   * @return The Java object.
+   * @param objectRef The reference of the object to get. Returns The Java object.
    */
   <T> T get(ObjectRef<T> objectRef);
 
   /**
    * Get a list of objects from the object store.
    *
-   * @param objectRefs The list of object references.
-   * @return A list of Java objects.
+   * @param objectRefs The list of object references. Returns A list of Java objects.
    */
   <T> List<T> get(List<ObjectRef<T>> objectRefs);
 
@@ -62,8 +56,8 @@ public interface RayRuntime {
    *
    * @param waitList A list of ObjectRef to wait for.
    * @param numReturns The number of objects that should be returned.
-   * @param timeoutMs The maximum time in milliseconds to wait before returning.
-   * @return Two lists, one containing locally available objects, one containing the rest.
+   * @param timeoutMs The maximum time in milliseconds to wait before returning. Returns Two lists,
+   *     one containing locally available objects, one containing the rest.
    */
   <T> WaitResult<T> wait(List<ObjectRef<T>> waitList, int numReturns, int timeoutMs);
 
@@ -88,13 +82,12 @@ public interface RayRuntime {
 
   /**
    * Get a handle to a named actor.
-   * <p>
-   * Gets a handle to a named actor with the given name. The actor must
-   * have been created with name specified.
+   *
+   * <p>Gets a handle to a named actor with the given name. The actor must have been created with
+   * name specified.
    *
    * @param name The name of the named actor.
-   * @param global Whether the named actor is global.
-   * @return ActorHandle to the actor.
+   * @param global Whether the named actor is global. Returns ActorHandle to the actor.
    */
   <T extends BaseActorHandle> Optional<T> getActor(String name, boolean global);
 
@@ -111,8 +104,7 @@ public interface RayRuntime {
    *
    * @param func The remote function to run.
    * @param args The arguments of the remote function.
-   * @param options The options for this call.
-   * @return The result object.
+   * @param options The options for this call. Returns The result object.
    */
   ObjectRef call(RayFunc func, Object[] args, CallOptions options);
 
@@ -121,8 +113,7 @@ public interface RayRuntime {
    *
    * @param pyFunction The Python function.
    * @param args Arguments of the function.
-   * @param options The options for this call.
-   * @return The result object.
+   * @param options The options for this call. Returns The result object.
    */
   ObjectRef call(PyFunction pyFunction, Object[] args, CallOptions options);
 
@@ -131,8 +122,7 @@ public interface RayRuntime {
    *
    * @param actor A handle to the actor.
    * @param func The remote function to run, it must be a method of the given actor.
-   * @param args The arguments of the remote function.
-   * @return The result object.
+   * @param args The arguments of the remote function. Returns The result object.
    */
   ObjectRef callActor(ActorHandle<?> actor, RayFunc func, Object[] args);
 
@@ -141,8 +131,7 @@ public interface RayRuntime {
    *
    * @param pyActor A handle to the actor.
    * @param pyActorMethod The actor method.
-   * @param args Arguments of the function.
-   * @return The result object.
+   * @param args Arguments of the function. Returns The result object.
    */
   ObjectRef callActor(PyActorHandle pyActor, PyActorMethod pyActorMethod, Object[] args);
 
@@ -152,28 +141,25 @@ public interface RayRuntime {
    * @param actorFactoryFunc A remote function whose return value is the actor object.
    * @param args The arguments for the remote function.
    * @param <T> The type of the actor object.
-   * @param options The options for creating actor.
-   * @return A handle to the actor.
+   * @param options The options for creating actor. Returns A handle to the actor.
    */
-  <T> ActorHandle<T> createActor(RayFunc actorFactoryFunc, Object[] args,
-                                 ActorCreationOptions options);
+  <T> ActorHandle<T> createActor(
+      RayFunc actorFactoryFunc, Object[] args, ActorCreationOptions options);
 
   /**
    * Create a Python actor on a remote node.
    *
    * @param pyActorClass The Python actor class.
    * @param args Arguments of the actor constructor.
-   * @param options The options for creating actor.
-   * @return A handle to the actor.
+   * @param options The options for creating actor. Returns A handle to the actor.
    */
-  PyActorHandle createActor(PyActorClass pyActorClass, Object[] args,
-                            ActorCreationOptions options);
+  PyActorHandle createActor(PyActorClass pyActorClass, Object[] args, ActorCreationOptions options);
 
-  PlacementGroup createPlacementGroup(String name, List<Map<String, Double>> bundles,
-      PlacementStrategy strategy);
+  PlacementGroup createPlacementGroup(
+      String name, List<Map<String, Double>> bundles, PlacementStrategy strategy);
 
-  PlacementGroup createPlacementGroup(List<Map<String, Double>> bundles,
-      PlacementStrategy strategy);
+  PlacementGroup createPlacementGroup(
+      List<Map<String, Double>> bundles, PlacementStrategy strategy);
 
   RuntimeContext getRuntimeContext();
 
@@ -184,48 +170,47 @@ public interface RayRuntime {
   /**
    * Wrap a {@link Runnable} with necessary context capture.
    *
-   * @param runnable The runnable to wrap.
-   * @return The wrapped runnable.
+   * @param runnable The runnable to wrap. Returns The wrapped runnable.
    */
   Runnable wrapRunnable(Runnable runnable);
 
   /**
    * Wrap a {@link Callable} with necessary context capture.
    *
-   * @param callable The callable to wrap.
-   * @return The wrapped callable.
+   * @param callable The callable to wrap. Returns The wrapped callable.
    */
   <T> Callable<T> wrapCallable(Callable<T> callable);
 
-  /**
-   * Intentionally exit the current actor.
-   */
+  /** Intentionally exit the current actor. */
   void exitActor();
 
   /**
    * Get a placement group by id.
-   * @param id placement group id.
-   * @return The placement group.
+   *
+   * @param id placement group id. Returns The placement group.
    */
   PlacementGroup getPlacementGroup(PlacementGroupId id);
 
   /**
    * Get all placement groups in this cluster.
-   * @return All placement groups.
+   *
+   * <p>Returns All placement groups.
    */
   List<PlacementGroup> getAllPlacementGroups();
 
   /**
    * Remove a placement group by id.
+   *
    * @param id Id of the placement group.
    */
   void removePlacementGroup(PlacementGroupId id);
 
   /**
    * Wait for the placement group to be ready within the specified time.
+   *
    * @param id Id of placement group.
-   * @param timeoutMs Timeout in milliseconds.
-   * @return True if the placement group is created. False otherwise.
+   * @param timeoutMs Timeout in milliseconds. Returns True if the placement group is created. False
+   *     otherwise.
    */
   boolean waitPlacementGroupReady(PlacementGroupId id, int timeoutMs);
 }

java/api/src/main/java/io/ray/api/runtime/RayRuntimeFactory.java

@@ -1,8 +1,6 @@
 package io.ray.api.runtime;
 
-/**
- * A factory that produces a RayRuntime instance.
- */
+/** A factory that produces a RayRuntime instance. */
 public interface RayRuntimeFactory {
 
   RayRuntime createRayRuntime();

java/api/src/main/java/io/ray/api/runtimecontext/NodeInfo.java

@@ -3,9 +3,7 @@ package io.ray.api.runtimecontext;
 import io.ray.api.id.UniqueId;
 import java.util.Map;
 
-/**
- * A class that represents the information of a node.
- */
+/** A class that represents the information of a node. */
 public class NodeInfo {
 
   public final UniqueId nodeId;
@@ -24,9 +22,15 @@ public class NodeInfo {
 
   public final Map<String, Double> resources;
 
-  public NodeInfo(UniqueId nodeId,  String nodeAddress, String nodeHostname, int nodeManagerPort,
-                  String objectStoreSocketName, String rayletSocketName,
-                  boolean isAlive, Map<String, Double> resources) {
+  public NodeInfo(
+      UniqueId nodeId,
+      String nodeAddress,
+      String nodeHostname,
+      int nodeManagerPort,
+      String objectStoreSocketName,
+      String rayletSocketName,
+      boolean isAlive,
+      Map<String, Double> resources) {
     this.nodeId = nodeId;
     this.nodeAddress = nodeAddress;
     this.nodeHostname = nodeHostname;
@@ -39,12 +43,19 @@ public class NodeInfo {
 
   public String toString() {
     return "NodeInfo{"
-        + "nodeId='" + nodeId + '\''
-        + ", nodeAddress='" + nodeAddress + "\'"
-        + ", nodeHostname'" + nodeHostname + "\'"
-        + ", isAlive=" + isAlive
-        + ", resources=" + resources
+        + "nodeId='"
+        + nodeId
+        + '\''
+        + ", nodeAddress='"
+        + nodeAddress
+        + "\'"
+        + ", nodeHostname'"
+        + nodeHostname
+        + "\'"
+        + ", isAlive="
+        + isAlive
+        + ", resources="
+        + resources
         + "}";
   }
-
 }

java/api/src/main/java/io/ray/api/runtimecontext/RuntimeContext.java

@@ -4,27 +4,23 @@ import io.ray.api.id.ActorId;
 import io.ray.api.id.JobId;
 import java.util.List;
 
-/**
- * A class used for getting information of Ray runtime.
- */
+/** A class used for getting information of Ray runtime. */
 public interface RuntimeContext {
 
-  /**
-   * Get the current Job ID.
-   */
+  /** Get the current Job ID. */
   JobId getCurrentJobId();
 
   /**
    * Get the current actor ID.
    *
-   * Note, this can only be called in actors.
+   * <p>Note, this can only be called in actors.
    */
   ActorId getCurrentActorId();
 
   /**
    * Returns true if the current actor was restarted, false if it's created for the first time.
    *
-   * Note, this method should only be called from an actor creation task.
+   * <p>Note, this method should only be called from an actor creation task.
    */
   boolean wasCurrentActorRestarted();
 
@@ -33,8 +29,6 @@ public interface RuntimeContext {
    */
   boolean isSingleProcess();
 
-  /**
-   * Get all node information in Ray cluster.
-   */
+  /** Get all node information in Ray cluster. */
   List<NodeInfo> getAllNodeInfo();
 }

java/checkstyle-suppressions.xml

@@ -4,13 +4,4 @@
 
 <suppressions>
   <suppress checks="OperatorWrap" files=".*" />
-  <suppress checks="JavadocParagraph" files=".*" />
-  <suppress checks="SummaryJavadoc" files=".*" />
-  <suppress checks="MemberNameCheck" files="PathConfig.java"/>
-  <suppress checks="MemberNameCheck" files="RayParameters.java"/>
-  <suppress checks="AbbreviationAsWordInNameCheck" files="RayParameters.java"/>
-  <suppress checks=".*" files="RayCall.java"/>
-  <suppress checks=".*" files="ActorCall.java"/>
-  <!-- suppress check for flatbuffer-generated files. -->
-  <suppress checks=".*" files="io[\\/]ray[\\/]runtime[\\/]generated[\\/]" />
 </suppressions>

java/checkstyle.xml

@@ -26,6 +26,11 @@
     <module name="FileTabCharacter">
         <property name="eachLine" value="true"/>
     </module>
+    <!-- exclude the generated files from being parsed, which make checkstyle check more fast -->
+    <module name="BeforeExecutionExclusionFileFilter">
+        <property name="fileNamePattern"
+                  value="io[\\/]ray[\\/].*runtime[\\/]generated[\\/]|RayCall.java|ActorCall.java"/>
+    </module>
 
     <module name="TreeWalker">
         <!-- Below are custom config items in addition to the original google style config. -->
@@ -58,20 +63,6 @@
                       value="LITERAL_TRY, LITERAL_FINALLY, LITERAL_IF, LITERAL_ELSE, LITERAL_SWITCH"/>
         </module>
         <module name="NeedBraces"/>
-        <module name="LeftCurly"/>
-        <module name="RightCurly">
-            <property name="id" value="RightCurlySame"/>
-            <property name="tokens"
-                      value="LITERAL_TRY, LITERAL_CATCH, LITERAL_FINALLY, LITERAL_IF, LITERAL_ELSE,
-                    LITERAL_DO"/>
-        </module>
-        <module name="RightCurly">
-            <property name="id" value="RightCurlyAlone"/>
-            <property name="option" value="alone"/>
-            <property name="tokens"
-                      value="CLASS_DEF, METHOD_DEF, CTOR_DEF, LITERAL_FOR, LITERAL_WHILE, STATIC_INIT,
-                    INSTANCE_INIT"/>
-        </module>
         <module name="WhitespaceAround">
             <property name="allowEmptyConstructors" value="true"/>
             <property name="allowEmptyMethods" value="true"/>
@@ -164,14 +155,6 @@
             <message key="ws.notPreceded"
                      value="GenericWhitespace ''{0}'' is not preceded with whitespace."/>
         </module>
-        <module name="Indentation">
-            <property name="basicOffset" value="2"/>
-            <property name="braceAdjustment" value="0"/>
-            <property name="caseIndent" value="2"/>
-            <property name="throwsIndent" value="4"/>
-            <property name="lineWrappingIndentation" value="4"/>
-            <property name="arrayInitIndent" value="2"/>
-        </module>
         <module name="AbbreviationAsWordInName">
             <property name="ignoreFinal" value="false"/>
             <property name="allowedAbbreviationLength" value="1"/>
@@ -232,9 +215,6 @@
             <message key="name.invalidPattern"
                      value="Method name ''{0}'' must match pattern ''{1}''."/>
         </module>
-        <module name="SingleLineJavadoc">
-        <property name="ignoreInlineTags" value="false"/>
-        </module>
         <module name="EmptyCatchBlock">
             <property name="exceptionVariableName" value="expected"/>
         </module>

java/pom.xml

@@ -63,6 +63,7 @@
     <java.version>1.8</java.version>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <projetct.version>1.1.0-SNAPSHOT</projetct.version>
+    <projetct.version>1.1.0-SNAPSHOT</projetct.version>
   </properties>
 
   <profiles>
@@ -176,7 +177,14 @@
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-checkstyle-plugin</artifactId>
-          <version>3.0.0</version>
+          <version>3.1.0</version>
+          <dependencies>
+            <dependency>
+              <groupId>com.puppycrawl.tools</groupId>
+              <artifactId>checkstyle</artifactId>
+              <version>8.19</version>
+            </dependency>
+          </dependencies>
           <executions>
             <execution>
               <id>validate</id>
@@ -218,6 +226,26 @@
             </execution>
           </executions>
         </plugin>
+
+        <plugin>
+          <groupId>com.diffplug.spotless</groupId>
+          <artifactId>spotless-maven-plugin</artifactId>
+          <version>2.5.0</version>
+          <configuration>
+            <java>
+              <excludes>
+                <exclude>**/RayCall.java</exclude>
+                <exclude>**/ActorCall.java</exclude>
+                <exclude>**/PyActorCall.java</exclude>
+                <exclude>**/runtime/generated/**/*.*</exclude>
+              </excludes>
+              <googleJavaFormat>
+                <version>1.7</version>
+                <style>GOOGLE</style>
+              </googleJavaFormat>
+            </java>
+          </configuration>
+        </plugin>
       </plugins>
     </pluginManagement>
     <plugins>
@@ -229,6 +257,10 @@
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-source-plugin</artifactId>
       </plugin>
+      <plugin>
+        <groupId>com.diffplug.spotless</groupId>
+        <artifactId>spotless-maven-plugin</artifactId>
+      </plugin>
     </plugins>
   </build>
 

java/runtime/src/main/java/io/ray/runtime/AbstractRayRuntime.java

@@ -45,9 +45,7 @@ import java.util.stream.Collectors;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-/**
- * Core functionality to implement Ray APIs.
- */
+/** Core functionality to implement Ray APIs. */
 public abstract class AbstractRayRuntime implements RayRuntimeInternal {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(AbstractRayRuntime.class);
@@ -63,9 +61,7 @@ public abstract class AbstractRayRuntime implements RayRuntimeInternal {
   protected TaskSubmitter taskSubmitter;
   protected WorkerContext workerContext;
 
-  /**
-   * Whether the required thread context is set on the current thread.
-   */
+  /** Whether the required thread context is set on the current thread. */
   final ThreadLocal<Boolean> isContextSet = ThreadLocal.withInitial(() -> false);
 
   public AbstractRayRuntime(RayConfig rayConfig) {
@@ -78,7 +74,7 @@ public abstract class AbstractRayRuntime implements RayRuntimeInternal {
   @Override
   public <T> ObjectRef<T> put(T obj) {
     ObjectId objectId = objectStore.put(obj);
-    return new ObjectRefImpl<T>(objectId, (Class<T>)(obj == null ? Object.class : obj.getClass()));
+    return new ObjectRefImpl<T>(objectId, (Class<T>) (obj == null ? Object.class : obj.getClass()));
   }
 
   @Override
@@ -101,8 +97,11 @@ public abstract class AbstractRayRuntime implements RayRuntimeInternal {
 
   @Override
   public void free(List<ObjectRef<?>> objectRefs, boolean localOnly) {
-    objectStore.delete(objectRefs.stream().map(ref -> ((ObjectRefImpl<?>) ref).getId()).collect(
-        Collectors.toList()), localOnly);
+    objectStore.delete(
+        objectRefs.stream()
+            .map(ref -> ((ObjectRefImpl<?>) ref).getId())
+            .collect(Collectors.toList()),
+        localOnly);
   }
 
   @Override
@@ -120,13 +119,11 @@ public abstract class AbstractRayRuntime implements RayRuntimeInternal {
 
   @Override
   public ObjectRef call(PyFunction pyFunction, Object[] args, CallOptions options) {
-    PyFunctionDescriptor functionDescriptor = new PyFunctionDescriptor(
-        pyFunction.moduleName,
-        "",
-        pyFunction.functionName);
+    PyFunctionDescriptor functionDescriptor =
+        new PyFunctionDescriptor(pyFunction.moduleName, "", pyFunction.functionName);
     // Python functions always have a return value, even if it's `None`.
-    return callNormalFunction(functionDescriptor, args,
-        /*returnType=*/Optional.of(pyFunction.returnType), options);
+    return callNormalFunction(
+        functionDescriptor, args, /*returnType=*/ Optional.of(pyFunction.returnType), options);
   }
 
   @Override
@@ -139,17 +136,18 @@ public abstract class AbstractRayRuntime implements RayRuntimeInternal {
 
   @Override
   public ObjectRef callActor(PyActorHandle pyActor, PyActorMethod pyActorMethod, Object... args) {
-    PyFunctionDescriptor functionDescriptor = new PyFunctionDescriptor(pyActor.getModuleName(),
-        pyActor.getClassName(), pyActorMethod.methodName);
+    PyFunctionDescriptor functionDescriptor =
+        new PyFunctionDescriptor(
+            pyActor.getModuleName(), pyActor.getClassName(), pyActorMethod.methodName);
     // Python functions always have a return value, even if it's `None`.
-    return callActorFunction(pyActor, functionDescriptor, args,
-        /*returnType=*/Optional.of(pyActorMethod.returnType));
+    return callActorFunction(
+        pyActor, functionDescriptor, args, /*returnType=*/ Optional.of(pyActorMethod.returnType));
   }
 
   @Override
   @SuppressWarnings("unchecked")
-  public <T> ActorHandle<T> createActor(RayFunc actorFactoryFunc,
-                                        Object[] args, ActorCreationOptions options) {
+  public <T> ActorHandle<T> createActor(
+      RayFunc actorFactoryFunc, Object[] args, ActorCreationOptions options) {
     FunctionDescriptor functionDescriptor =
         functionManager.getFunction(workerContext.getCurrentJobId(), actorFactoryFunc)
             .functionDescriptor;
@@ -157,20 +155,20 @@ public abstract class AbstractRayRuntime implements RayRuntimeInternal {
   }
 
   @Override
-  public PyActorHandle createActor(PyActorClass pyActorClass, Object[] args,
-                                   ActorCreationOptions options) {
-    PyFunctionDescriptor functionDescriptor = new PyFunctionDescriptor(
-        pyActorClass.moduleName,
-        pyActorClass.className,
-        PYTHON_INIT_METHOD_NAME);
+  public PyActorHandle createActor(
+      PyActorClass pyActorClass, Object[] args, ActorCreationOptions options) {
+    PyFunctionDescriptor functionDescriptor =
+        new PyFunctionDescriptor(
+            pyActorClass.moduleName, pyActorClass.className, PYTHON_INIT_METHOD_NAME);
     return (PyActorHandle) createActorImpl(functionDescriptor, args, options);
   }
 
   @Override
-  public PlacementGroup createPlacementGroup(String name,
-      List<Map<String, Double>> bundles, PlacementStrategy strategy) {
-    boolean bundleResourceValid = bundles.stream().allMatch(
-        bundle -> bundle.values().stream().allMatch(resource -> resource > 0));
+  public PlacementGroup createPlacementGroup(
+      String name, List<Map<String, Double>> bundles, PlacementStrategy strategy) {
+    boolean bundleResourceValid =
+        bundles.stream()
+            .allMatch(bundle -> bundle.values().stream().allMatch(resource -> resource > 0));
 
     if (bundles.isEmpty() || !bundleResourceValid) {
       throw new IllegalArgumentException(
@@ -264,12 +262,13 @@ public abstract class AbstractRayRuntime implements RayRuntimeInternal {
 
   private ObjectRef callNormalFunction(
       FunctionDescriptor functionDescriptor,
-      Object[] args, Optional<Class<?>> returnType, CallOptions options) {
+      Object[] args,
+      Optional<Class<?>> returnType,
+      CallOptions options) {
     int numReturns = returnType.isPresent() ? 1 : 0;
-    List<FunctionArg> functionArgs = ArgumentsBuilder
-        .wrap(args, functionDescriptor.getLanguage());
-    List<ObjectId> returnIds = taskSubmitter.submitTask(functionDescriptor,
-        functionArgs, numReturns, options);
+    List<FunctionArg> functionArgs = ArgumentsBuilder.wrap(args, functionDescriptor.getLanguage());
+    List<ObjectId> returnIds =
+        taskSubmitter.submitTask(functionDescriptor, functionArgs, numReturns, options);
     Preconditions.checkState(returnIds.size() == numReturns);
     if (returnIds.isEmpty()) {
       return null;
@@ -284,10 +283,9 @@ public abstract class AbstractRayRuntime implements RayRuntimeInternal {
       Object[] args,
       Optional<Class<?>> returnType) {
     int numReturns = returnType.isPresent() ? 1 : 0;
-    List<FunctionArg> functionArgs = ArgumentsBuilder
-        .wrap(args, functionDescriptor.getLanguage());
-    List<ObjectId> returnIds = taskSubmitter.submitActorTask(rayActor,
-        functionDescriptor, functionArgs, numReturns, null);
+    List<FunctionArg> functionArgs = ArgumentsBuilder.wrap(args, functionDescriptor.getLanguage());
+    List<ObjectId> returnIds =
+        taskSubmitter.submitActorTask(rayActor, functionDescriptor, functionArgs, numReturns, null);
     Preconditions.checkState(returnIds.size() == numReturns);
     if (returnIds.isEmpty()) {
       return null;
@@ -296,10 +294,9 @@ public abstract class AbstractRayRuntime implements RayRuntimeInternal {
     }
   }
 
-  private BaseActorHandle createActorImpl(FunctionDescriptor functionDescriptor,
-                                          Object[] args, ActorCreationOptions options) {
-    List<FunctionArg> functionArgs = ArgumentsBuilder
-        .wrap(args, functionDescriptor.getLanguage());
+  private BaseActorHandle createActorImpl(
+      FunctionDescriptor functionDescriptor, Object[] args, ActorCreationOptions options) {
+    List<FunctionArg> functionArgs = ArgumentsBuilder.wrap(args, functionDescriptor.getLanguage());
     if (functionDescriptor.getLanguage() != Language.JAVA && options != null) {
       Preconditions.checkState(Strings.isNullOrEmpty(options.jvmOptions));
     }

java/runtime/src/main/java/io/ray/runtime/DefaultRayRuntimeFactory.java

@@ -9,9 +9,7 @@ import io.ray.runtime.util.LoggingUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-/**
- * The default Ray runtime factory. It produces an instance of RayRuntime.
- */
+/** The default Ray runtime factory. It produces an instance of RayRuntime. */
 public class DefaultRayRuntimeFactory implements RayRuntimeFactory {
 
   @Override
@@ -22,17 +20,20 @@ public class DefaultRayRuntimeFactory implements RayRuntimeFactory {
 
     if (rayConfig.workerMode == WorkerType.WORKER) {
       // Handle the uncaught exceptions thrown from user-spawned threads.
-      Thread.setDefaultUncaughtExceptionHandler((Thread t, Throwable e) -> {
+      Thread.setDefaultUncaughtExceptionHandler(
+          (Thread t, Throwable e) -> {
             logger.error(String.format("Uncaught worker exception in thread %s", t), e);
           });
     }
 
     try {
       logger.debug("Initializing runtime with config: {}", rayConfig);
-      AbstractRayRuntime innerRuntime = rayConfig.runMode == RunMode.SINGLE_PROCESS
+      AbstractRayRuntime innerRuntime =
+          rayConfig.runMode == RunMode.SINGLE_PROCESS
               ? new RayDevRuntime(rayConfig)
               : new RayNativeRuntime(rayConfig);
-      RayRuntimeInternal runtime = rayConfig.numWorkersPerProcess > 1
+      RayRuntimeInternal runtime =
+          rayConfig.numWorkersPerProcess > 1
               ? RayRuntimeProxy.newInstance(innerRuntime)
               : innerRuntime;
       runtime.start();

java/runtime/src/main/java/io/ray/runtime/RayDevRuntime.java

@@ -35,9 +35,10 @@ public class RayDevRuntime extends AbstractRayRuntime {
     taskExecutor = new LocalModeTaskExecutor(this);
     workerContext = new LocalModeWorkerContext(rayConfig.getJobId());
     objectStore = new LocalModeObjectStore(workerContext);
-    taskSubmitter = new LocalModeTaskSubmitter(this, taskExecutor,
-        (LocalModeObjectStore) objectStore);
-    ((LocalModeObjectStore) objectStore).addObjectPutCallback(
+    taskSubmitter =
+        new LocalModeTaskSubmitter(this, taskExecutor, (LocalModeObjectStore) objectStore);
+    ((LocalModeObjectStore) objectStore)
+        .addObjectPutCallback(
             objectId -> {
               if (taskSubmitter != null) {
                 ((LocalModeTaskSubmitter) taskSubmitter).onObjectPut(objectId);
@@ -72,7 +73,7 @@ public class RayDevRuntime extends AbstractRayRuntime {
   @SuppressWarnings("unchecked")
   @Override
   public <T extends BaseActorHandle> Optional<T> getActor(String name, boolean global) {
-    return (Optional<T>) ((LocalModeTaskSubmitter)taskSubmitter).getActor(name, global);
+    return (Optional<T>) ((LocalModeTaskSubmitter) taskSubmitter).getActor(name, global);
   }
 
   @Override
@@ -87,24 +88,21 @@ public class RayDevRuntime extends AbstractRayRuntime {
   }
 
   @Override
-  public PlacementGroup getPlacementGroup(
-      PlacementGroupId id) {
-    //@TODO(clay4444): We need a LocalGcsClient before implements this.
+  public PlacementGroup getPlacementGroup(PlacementGroupId id) {
+    // @TODO(clay4444): We need a LocalGcsClient before implements this.
     throw new UnsupportedOperationException(
         "Ray doesn't support placement group operations in local mode.");
   }
 
   @Override
   public List<PlacementGroup> getAllPlacementGroups() {
-    //@TODO(clay4444): We need a LocalGcsClient before implements this.
+    // @TODO(clay4444): We need a LocalGcsClient before implements this.
     throw new UnsupportedOperationException(
         "Ray doesn't support placement group operations in local mode.");
   }
 
   @Override
-  public void exitActor() {
-
-  }
+  public void exitActor() {}
 
   private JobId nextJobId() {
     return JobId.fromInt(jobCounter.getAndIncrement());

java/runtime/src/main/java/io/ray/runtime/RayNativeRuntime.java

@@ -29,9 +29,7 @@ import java.util.concurrent.locks.ReentrantReadWriteLock;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-/**
- * Native runtime for cluster mode.
- */
+/** Native runtime for cluster mode. */
 public final class RayNativeRuntime extends AbstractRayRuntime {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(RayNativeRuntime.class);
@@ -39,10 +37,9 @@ public final class RayNativeRuntime extends AbstractRayRuntime {
   private boolean startRayHead = false;
 
   /**
-   * In Java, GC runs in a standalone thread, and we can't control the exact
-   * timing of garbage collection. By using this lock, when
-   * {@link NativeObjectStore#nativeRemoveLocalReference} is executing, the core
-   * worker will not be shut down, therefore it guarantees some kind of
+   * In Java, GC runs in a standalone thread, and we can't control the exact timing of garbage
+   * collection. By using this lock, when {@link NativeObjectStore#nativeRemoveLocalReference} is
+   * executing, the core worker will not be shut down, therefore it guarantees some kind of
    * thread-safety. Note that this guarantee only works for driver.
    */
   private final ReadWriteLock shutdownLock = new ReentrantReadWriteLock();
@@ -117,21 +114,29 @@ public final class RayNativeRuntime extends AbstractRayRuntime {
         rayletConfigStringMap.put(entry.getKey(), entry.getValue().toString());
       }
 
-      nativeInitialize(rayConfig.workerMode.getNumber(),
-          rayConfig.nodeIp, rayConfig.getNodeManagerPort(),
+      nativeInitialize(
+          rayConfig.workerMode.getNumber(),
+          rayConfig.nodeIp,
+          rayConfig.getNodeManagerPort(),
           rayConfig.workerMode == WorkerType.DRIVER ? System.getProperty("user.dir") : "",
-          rayConfig.objectStoreSocketName, rayConfig.rayletSocketName,
+          rayConfig.objectStoreSocketName,
+          rayConfig.rayletSocketName,
           (rayConfig.workerMode == WorkerType.DRIVER ? rayConfig.getJobId() : JobId.NIL).getBytes(),
-          new GcsClientOptions(rayConfig), numWorkersPerProcess,
-          rayConfig.logDir, rayletConfigStringMap, serializedJobConfig);
+          new GcsClientOptions(rayConfig),
+          numWorkersPerProcess,
+          rayConfig.logDir,
+          rayletConfigStringMap,
+          serializedJobConfig);
 
       taskExecutor = new NativeTaskExecutor(this);
       workerContext = new NativeWorkerContext();
       objectStore = new NativeObjectStore(workerContext, shutdownLock);
       taskSubmitter = new NativeTaskSubmitter();
 
-      LOGGER.debug("RayNativeRuntime started with store {}, raylet {}",
-          rayConfig.objectStoreSocketName, rayConfig.rayletSocketName);
+      LOGGER.debug(
+          "RayNativeRuntime started with store {}, raylet {}",
+          rayConfig.objectStoreSocketName,
+          rayConfig.rayletSocketName);
     } catch (Exception e) {
       if (startRayHead) {
         try {
@@ -201,8 +206,8 @@ public final class RayNativeRuntime extends AbstractRayRuntime {
 
   @Override
   public Object getAsyncContext() {
-    return new AsyncContext(workerContext.getCurrentWorkerId(),
-        workerContext.getCurrentClassLoader());
+    return new AsyncContext(
+        workerContext.getCurrentWorkerId(), workerContext.getCurrentClassLoader());
   }
 
   @Override
@@ -229,10 +234,18 @@ public final class RayNativeRuntime extends AbstractRayRuntime {
   }
 
   private static native void nativeInitialize(
-      int workerMode, String ndoeIpAddress,
-      int nodeManagerPort, String driverName, String storeSocket, String rayletSocket,
-      byte[] jobId, GcsClientOptions gcsClientOptions, int numWorkersPerProcess,
-      String logDir, Map<String, String> rayletConfigParameters, byte[] serializedJobConfig);
+      int workerMode,
+      String ndoeIpAddress,
+      int nodeManagerPort,
+      String driverName,
+      String storeSocket,
+      String rayletSocket,
+      byte[] jobId,
+      GcsClientOptions gcsClientOptions,
+      int numWorkersPerProcess,
+      String logDir,
+      Map<String, String> rayletConfigParameters,
+      byte[] serializedJobConfig);
 
   private static native void nativeRunTaskExecutor(TaskExecutor taskExecutor);
 

java/runtime/src/main/java/io/ray/runtime/RayRuntimeInternal.java

@@ -8,14 +8,10 @@ import io.ray.runtime.gcs.GcsClient;
 import io.ray.runtime.object.ObjectStore;
 import io.ray.runtime.task.TaskExecutor;
 
-/**
- * This interface is required to make {@link RayRuntimeProxy} work.
- */
+/** This interface is required to make {@link RayRuntimeProxy} work. */
 public interface RayRuntimeInternal extends RayRuntime {
 
-  /**
-   * Start runtime.
-   */
+  /** Start runtime. */
   void start();
 
   WorkerContext getWorkerContext();

java/runtime/src/main/java/io/ray/runtime/RayRuntimeProxy.java

@@ -13,9 +13,7 @@ import java.lang.reflect.Method;
  */
 public class RayRuntimeProxy implements InvocationHandler {
 
-  /**
-   * The original runtime.
-   */
+  /** The original runtime. */
   private AbstractRayRuntime obj;
 
   private RayRuntimeProxy(AbstractRayRuntime obj) {
@@ -26,19 +24,20 @@ public class RayRuntimeProxy implements InvocationHandler {
     return obj;
   }
 
-  /**
-   * Generate a new instance of {@link RayRuntimeInternal} with additional context check.
-   */
+  /** Generate a new instance of {@link RayRuntimeInternal} with additional context check. */
   static RayRuntimeInternal newInstance(AbstractRayRuntime obj) {
-    return (RayRuntimeInternal) java.lang.reflect.Proxy
-        .newProxyInstance(obj.getClass().getClassLoader(), new Class<?>[]{RayRuntimeInternal.class},
+    return (RayRuntimeInternal)
+        java.lang.reflect.Proxy.newProxyInstance(
+            obj.getClass().getClassLoader(),
+            new Class<?>[] {RayRuntimeInternal.class},
             new RayRuntimeProxy(obj));
   }
 
   @Override
   public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
-    if (isInterfaceMethod(method) && !method.getName().equals("shutdown") && !method.getName()
-        .equals("setAsyncContext")) {
+    if (isInterfaceMethod(method)
+        && !method.getName().equals("shutdown")
+        && !method.getName().equals("setAsyncContext")) {
       checkIsContextSet();
     }
     try {
@@ -52,9 +51,7 @@ public class RayRuntimeProxy implements InvocationHandler {
     }
   }
 
-  /**
-   * Whether the method is defined in the {@link RayRuntime} interface.
-   */
+  /** Whether the method is defined in the {@link RayRuntime} interface. */
   private boolean isInterfaceMethod(Method method) {
     try {
       RayRuntime.class.getMethod(method.getName(), method.getParameterTypes());
@@ -66,8 +63,8 @@ public class RayRuntimeProxy implements InvocationHandler {
 
   /**
    * Check if thread context is set.
-   * <p/>
-   * This method should be invoked at the beginning of most public methods of {@link RayRuntime},
+   *
+   * <p>This method should be invoked at the beginning of most public methods of {@link RayRuntime},
    * otherwise the native code might crash due to thread local core worker was not set. We check it
    * for {@link AbstractRayRuntime} instead of {@link RayNativeRuntime} because we want to catch the
    * error even if the application runs in {@link RunMode#SINGLE_PROCESS} mode.

java/runtime/src/main/java/io/ray/runtime/actor/LocalModeActorHandle.java

@@ -9,9 +9,7 @@ import java.io.ObjectInput;
 import java.io.ObjectOutput;
 import java.util.concurrent.atomic.AtomicReference;
 
-/**
- * Implementation of actor handle for local mode.
- */
+/** Implementation of actor handle for local mode. */
 public class LocalModeActorHandle implements ActorHandle, Externalizable {
 
   private ActorId actorId;
@@ -23,11 +21,8 @@ public class LocalModeActorHandle implements ActorHandle, Externalizable {
     this.previousActorTaskDummyObjectId.set(previousActorTaskDummyObjectId);
   }
 
-  /**
-   * Required by FST
-   */
-  public LocalModeActorHandle() {
-  }
+  /** Required by FST. */
+  public LocalModeActorHandle() {}
 
   @Override
   public ActorId getId() {

java/runtime/src/main/java/io/ray/runtime/actor/NativeActorHandle.java

@@ -16,9 +16,7 @@ import java.util.List;
  */
 public abstract class NativeActorHandle implements BaseActorHandle, Externalizable {
 
-  /**
-   * ID of the actor.
-   */
+  /** ID of the actor. */
   byte[] actorId;
 
   private Language language;
@@ -29,11 +27,8 @@ public abstract class NativeActorHandle implements BaseActorHandle, Externalizab
     this.language = language;
   }
 
-  /**
-   * Required by FST
-   */
-  NativeActorHandle() {
-  }
+  /** Required by FST. */
+  NativeActorHandle() {}
 
   public static NativeActorHandle create(byte[] actorId) {
     Language language = Language.forNumber(nativeGetLanguage(actorId));
@@ -76,7 +71,7 @@ public abstract class NativeActorHandle implements BaseActorHandle, Externalizab
   /**
    * Serialize this actor handle to bytes.
    *
-   * @return  the bytes of the actor handle
+   * <p>Returns the bytes of the actor handle
    */
   public byte[] toBytes() {
     return nativeSerialize(actorId);
@@ -85,7 +80,7 @@ public abstract class NativeActorHandle implements BaseActorHandle, Externalizab
   /**
    * Deserialize an actor handle from bytes.
    *
-   * @return  the bytes of an actor handle
+   * <p>Returns the bytes of an actor handle
    */
   public static NativeActorHandle fromBytes(byte[] bytes) {
     byte[] actorId = nativeDeserialize(bytes);

java/runtime/src/main/java/io/ray/runtime/actor/NativeActorHandleSerializer.java

@@ -7,20 +7,24 @@ import org.nustaq.serialization.FSTClazzInfo.FSTFieldInfo;
 import org.nustaq.serialization.FSTObjectInput;
 import org.nustaq.serialization.FSTObjectOutput;
 
-/**
- * To deal with serialization about {@link NativeActorHandle}.
- */
+/** To deal with serialization about {@link NativeActorHandle}. */
 public class NativeActorHandleSerializer extends FSTBasicObjectSerializer {
 
   @Override
-  public void writeObject(FSTObjectOutput out, Object toWrite, FSTClazzInfo clzInfo,
-      FSTClazzInfo.FSTFieldInfo referencedBy, int streamPosition) throws IOException {
+  public void writeObject(
+      FSTObjectOutput out,
+      Object toWrite,
+      FSTClazzInfo clzInfo,
+      FSTClazzInfo.FSTFieldInfo referencedBy,
+      int streamPosition)
+      throws IOException {
     ((NativeActorHandle) toWrite).writeExternal(out);
   }
 
   @Override
-  public void readObject(FSTObjectInput in, Object toRead, FSTClazzInfo clzInfo,
-      FSTFieldInfo referencedBy) throws Exception {
+  public void readObject(
+      FSTObjectInput in, Object toRead, FSTClazzInfo clzInfo, FSTFieldInfo referencedBy)
+      throws Exception {
     super.readObject(in, toRead, clzInfo, referencedBy);
     ((NativeActorHandle) toRead).readExternal(in);
   }

java/runtime/src/main/java/io/ray/runtime/actor/NativeJavaActorHandle.java

@@ -6,18 +6,14 @@ import io.ray.runtime.generated.Common.Language;
 import java.io.IOException;
 import java.io.ObjectInput;
 
-/**
- * Java implementation of actor handle for cluster mode.
- */
+/** Java implementation of actor handle for cluster mode. */
 public class NativeJavaActorHandle extends NativeActorHandle implements ActorHandle {
 
   NativeJavaActorHandle(byte[] actorId) {
     super(actorId, Language.JAVA);
   }
 
-  /**
-   * Required by FST
-   */
+  /** Required by FST. */
   public NativeJavaActorHandle() {
     super();
   }

java/runtime/src/main/java/io/ray/runtime/actor/NativePyActorHandle.java

@@ -6,18 +6,14 @@ import io.ray.runtime.generated.Common.Language;
 import java.io.IOException;
 import java.io.ObjectInput;
 
-/**
- * Python actor handle implementation for cluster mode.
- */
+/** Python actor handle implementation for cluster mode. */
 public class NativePyActorHandle extends NativeActorHandle implements PyActorHandle {
 
   NativePyActorHandle(byte[] actorId) {
     super(actorId, Language.PYTHON);
   }
 
-  /**
-   * Required by FST
-   */
+  /** Required by FST. */
   public NativePyActorHandle() {
     super();
   }

java/runtime/src/main/java/io/ray/runtime/config/RayConfig.java

@@ -20,10 +20,7 @@ import org.apache.commons.lang3.BooleanUtils;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.commons.lang3.math.NumberUtils;
 
-/**
- * Configurations of Ray runtime.
- * See `ray.default.conf` for the meaning of each field.
- */
+/** Configurations of Ray runtime. See `ray.default.conf` for the meaning of each field. */
 public class RayConfig {
 
   public static final String DEFAULT_CONFIG_FILE = "ray.default.conf";
@@ -31,10 +28,9 @@ public class RayConfig {
 
   private Config config;
 
-  /**
-   * IP of this node. if not provided, IP will be automatically detected.
-   */
+  /** IP of this node. if not provided, IP will be automatically detected. */
   public final String nodeIp;
+
   public final WorkerType workerMode;
   public final RunMode runMode;
   private JobId jobId;
@@ -64,8 +60,8 @@ public class RayConfig {
 
   private void validate() {
     if (workerMode == WorkerType.WORKER) {
-      Preconditions.checkArgument(redisAddress != null,
-          "Redis address must be set in worker mode.");
+      Preconditions.checkArgument(
+          redisAddress != null, "Redis address must be set in worker mode.");
     }
   }
 
@@ -145,7 +141,8 @@ public class RayConfig {
     if (config.hasPath("ray.raylet.node-manager-port")) {
       nodeManagerPort = config.getInt("ray.raylet.node-manager-port");
     } else {
-      Preconditions.checkState(workerMode != WorkerType.WORKER,
+      Preconditions.checkState(
+          workerMode != WorkerType.WORKER,
           "Worker started by raylet should accept the node manager port from raylet.");
     }
 
@@ -217,9 +214,7 @@ public class RayConfig {
     return config;
   }
 
-  /**
-   * Renders the config value as a HOCON string.
-   */
+  /** Renders the config value as a HOCON string. */
   @Override
   public String toString() {
     // These items might be dynamically generated or mutated at runtime.
@@ -257,10 +252,8 @@ public class RayConfig {
   }
 
   /**
-   * Create a RayConfig by reading configuration in the following order:
-   * 1. System properties.
-   * 2. `ray.conf` file.
-   * 3. `ray.default.conf` file.
+   * Create a RayConfig by reading configuration in the following order: 1. System properties. 2.
+   * `ray.conf` file. 3. `ray.default.conf` file.
    */
   public static RayConfig create() {
     ConfigFactory.invalidateCaches();
@@ -274,5 +267,4 @@ public class RayConfig {
     config = config.withFallback(ConfigFactory.load(DEFAULT_CONFIG_FILE));
     return new RayConfig(config.withOnlyPath("ray"));
   }
-
 }

java/runtime/src/main/java/io/ray/runtime/config/RunMode.java

@@ -3,13 +3,11 @@ package io.ray.runtime.config;
 public enum RunMode {
 
   /**
-   * Ray is running in one single Java process, without Raylet backend, object store, and GCS.
-   * It's useful for debug.
+   * Ray is running in one single Java process, without Raylet backend, object store, and GCS. It's
+   * useful for debug.
    */
   SINGLE_PROCESS,
 
-  /**
-   * Ray is running on one or more nodes, with multiple processes.
-   */
+  /** Ray is running on one or more nodes, with multiple processes. */
   CLUSTER,
 }

java/runtime/src/main/java/io/ray/runtime/context/LocalModeWorkerContext.java

@@ -10,9 +10,7 @@ import io.ray.runtime.generated.Common.TaskSpec;
 import io.ray.runtime.generated.Common.TaskType;
 import io.ray.runtime.task.LocalModeTaskSubmitter;
 
-/**
- * Worker context for local mode.
- */
+/** Worker context for local mode. */
 public class LocalModeWorkerContext implements WorkerContext {
 
   private final JobId jobId;
@@ -52,8 +50,7 @@ public class LocalModeWorkerContext implements WorkerContext {
   }
 
   @Override
-  public void setCurrentClassLoader(ClassLoader currentClassLoader) {
-  }
+  public void setCurrentClassLoader(ClassLoader currentClassLoader) {}
 
   @Override
   public TaskType getCurrentTaskType() {

java/runtime/src/main/java/io/ray/runtime/context/NativeWorkerContext.java

@@ -9,9 +9,7 @@ import io.ray.runtime.generated.Common.Address;
 import io.ray.runtime.generated.Common.TaskType;
 import java.nio.ByteBuffer;
 
-/**
- * Worker context for cluster mode. This is a wrapper class for worker context of core worker.
- */
+/** Worker context for cluster mode. This is a wrapper class for worker context of core worker. */
 public class NativeWorkerContext implements WorkerContext {
 
   private final ThreadLocal<ClassLoader> currentClassLoader = new ThreadLocal<>();

java/runtime/src/main/java/io/ray/runtime/context/RuntimeContextImpl.java

@@ -26,15 +26,16 @@ public class RuntimeContextImpl implements RuntimeContext {
   @Override
   public ActorId getCurrentActorId() {
     ActorId actorId = runtime.getWorkerContext().getCurrentActorId();
-    Preconditions.checkState(actorId != null && !actorId.isNil(),
-        "This method should only be called from an actor.");
+    Preconditions.checkState(
+        actorId != null && !actorId.isNil(), "This method should only be called from an actor.");
     return actorId;
   }
 
   @Override
   public boolean wasCurrentActorRestarted() {
     TaskType currentTaskType = runtime.getWorkerContext().getCurrentTaskType();
-    Preconditions.checkState(currentTaskType == TaskType.ACTOR_CREATION_TASK,
+    Preconditions.checkState(
+        currentTaskType == TaskType.ACTOR_CREATION_TASK,
         "This method can only be called from an actor creation task.");
     if (isSingleProcess()) {
       return false;

java/runtime/src/main/java/io/ray/runtime/context/WorkerContext.java

@@ -7,24 +7,16 @@ import io.ray.api.id.UniqueId;
 import io.ray.runtime.generated.Common.Address;
 import io.ray.runtime.generated.Common.TaskType;
 
-/**
- * The context of worker.
- */
+/** The context of worker. */
 public interface WorkerContext {
 
-  /**
-   * ID of the current worker.
-   */
+  /** ID of the current worker. */
   UniqueId getCurrentWorkerId();
 
-  /**
-   * ID of the current job.
-   */
+  /** ID of the current job. */
   JobId getCurrentJobId();
 
-  /**
-   * ID of the current actor.
-   */
+  /** ID of the current actor. */
   ActorId getCurrentActorId();
 
   /**
@@ -33,19 +25,13 @@ public interface WorkerContext {
    */
   ClassLoader getCurrentClassLoader();
 
-  /**
-   * Set the current class loader.
-   */
+  /** Set the current class loader. */
   void setCurrentClassLoader(ClassLoader currentClassLoader);
 
-  /**
-   * Type of the current task.
-   */
+  /** Type of the current task. */
   TaskType getCurrentTaskType();
 
-  /**
-   * ID of the current task.
-   */
+  /** ID of the current task. */
   TaskId getCurrentTaskId();
 
   Address getRpcAddress();

java/runtime/src/main/java/io/ray/runtime/exception/CrossLanguageException.java

@@ -7,8 +7,10 @@ public class CrossLanguageException extends RayException {
   private Language language;
 
   public CrossLanguageException(io.ray.runtime.generated.Common.RayException exception) {
-    super(String.format("An exception raised from %s:\n%s", exception.getLanguage().name(),
-        exception.getFormattedExceptionString()));
+    super(
+        String.format(
+            "An exception raised from %s:\n%s",
+            exception.getLanguage().name(), exception.getFormattedExceptionString()));
     this.language = exception.getLanguage();
   }
 

java/runtime/src/main/java/io/ray/runtime/exception/RayActorException.java

@@ -5,7 +5,7 @@ import io.ray.api.id.ActorId;
 /**
  * Indicates that the actor died unexpectedly before finishing a task.
  *
- * This exception could happen either because the actor process dies while executing a task, or
+ * <p>This exception could happen either because the actor process dies while executing a task, or
  * because a task is submitted to a dead actor.
  */
 public class RayActorException extends RayException {
@@ -17,8 +17,7 @@ public class RayActorException extends RayException {
   }
 
   public RayActorException(ActorId actorId) {
-    super(String.format(
-        "The actor %s died unexpectedly before finishing this task.", actorId));
+    super(String.format("The actor %s died unexpectedly before finishing this task.", actorId));
     this.actorId = actorId;
   }
 
@@ -29,5 +28,4 @@ public class RayActorException extends RayException {
   public RayActorException(String message, Throwable cause) {
     super(message, cause);
   }
-
 }

java/runtime/src/main/java/io/ray/runtime/exception/RayException.java

@@ -16,8 +16,8 @@ public class RayException extends RuntimeException {
   }
 
   public byte[] toBytes() {
-    String formattedException = org.apache.commons.lang3.exception.ExceptionUtils
-        .getStackTrace(this);
+    String formattedException =
+        org.apache.commons.lang3.exception.ExceptionUtils.getStackTrace(this);
     io.ray.runtime.generated.Common.RayException.Builder builder =
         io.ray.runtime.generated.Common.RayException.newBuilder();
     builder.setLanguage(Language.JAVA);
@@ -26,13 +26,12 @@ public class RayException extends RuntimeException {
     return builder.build().toByteArray();
   }
 
-  public static RayException fromBytes(byte[] serialized)
-      throws InvalidProtocolBufferException {
+  public static RayException fromBytes(byte[] serialized) throws InvalidProtocolBufferException {
     io.ray.runtime.generated.Common.RayException exception =
         io.ray.runtime.generated.Common.RayException.parseFrom(serialized);
     if (exception.getLanguage() == Language.JAVA) {
-      return Serializer
-          .decode(exception.getSerializedException().toByteArray(), RayException.class);
+      return Serializer.decode(
+          exception.getSerializedException().toByteArray(), RayException.class);
     } else {
       return new CrossLanguageException(exception);
     }

java/runtime/src/main/java/io/ray/runtime/exception/RayIntentionalSystemExitException.java

@@ -1,8 +1,6 @@
 package io.ray.runtime.exception;
 
-/**
- * The exception represents that there is an intentional system exit.
- */
+/** The exception represents that there is an intentional system exit. */
 public class RayIntentionalSystemExitException extends RuntimeException {
 
   public RayIntentionalSystemExitException(String message) {

java/runtime/src/main/java/io/ray/runtime/exception/RayTaskException.java

@@ -6,8 +6,9 @@ import io.ray.runtime.util.SystemUtil;
 public class RayTaskException extends RayException {
 
   public RayTaskException(String message, Throwable cause) {
-    super(String.format("(pid=%d, ip=%s) %s",
-        SystemUtil.pid(), NetworkUtil.getIpAddress(null), message), cause);
+    super(
+        String.format(
+            "(pid=%d, ip=%s) %s", SystemUtil.pid(), NetworkUtil.getIpAddress(null), message),
+        cause);
   }
-
 }

java/runtime/src/main/java/io/ray/runtime/exception/RayWorkerException.java

@@ -1,8 +1,6 @@
 package io.ray.runtime.exception;
 
-/**
- * Indicates that the worker died unexpectedly while executing a task.
- */
+/** Indicates that the worker died unexpectedly while executing a task. */
 public class RayWorkerException extends RayException {
 
   public RayWorkerException() {
@@ -16,5 +14,4 @@ public class RayWorkerException extends RayException {
   public RayWorkerException(String message, Throwable cause) {
     super(message, cause);
   }
-
 }

java/runtime/src/main/java/io/ray/runtime/exception/UnreconstructableException.java

@@ -3,18 +3,18 @@ package io.ray.runtime.exception;
 import io.ray.api.id.ObjectId;
 
 /**
- * Indicates that an object is lost (either evicted or explicitly deleted) and cannot be
- * restarted.
+ * Indicates that an object is lost (either evicted or explicitly deleted) and cannot be restarted.
  *
- * Note, this exception only happens for actor objects. If actor's current state is after object's
- * creating task, the actor cannot re-run the task to reconstruct the object.
+ * <p>Note, this exception only happens for actor objects. If actor's current state is after
+ * object's creating task, the actor cannot re-run the task to reconstruct the object.
  */
 public class UnreconstructableException extends RayException {
 
   public ObjectId objectId;
 
   public UnreconstructableException(ObjectId objectId) {
-    super(String.format(
+    super(
+        String.format(
             "Object %s is lost (either evicted or explicitly deleted) and cannot be reconstructed.",
             objectId));
     this.objectId = objectId;
@@ -27,5 +27,4 @@ public class UnreconstructableException extends RayException {
   public UnreconstructableException(String message, Throwable cause) {
     super(message, cause);
   }
-
 }

java/runtime/src/main/java/io/ray/runtime/functionmanager/FunctionDescriptor.java

@@ -6,18 +6,14 @@ import java.util.List;
 /**
  * Base interface of a Ray task's function descriptor.
  *
- * A function descriptor is a list of strings that can uniquely describe a function. It's used to
+ * <p>A function descriptor is a list of strings that can uniquely describe a function. It's used to
  * load a function in workers.
  */
 public interface FunctionDescriptor {
 
-  /**
-   * @return A list of strings represents the functions.
-   */
+  /** Returns A list of strings represents the functions. */
   List<String> toList();
 
-  /**
-   * @return The language of the function.
-   */
+  /** Returns The language of the function. */
   Language getLanguage();
 }

java/runtime/src/main/java/io/ray/runtime/functionmanager/FunctionManager.java

@@ -34,9 +34,7 @@ import org.objectweb.asm.Type;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-/**
- * Manages functions by job id.
- */
+/** Manages functions by job id. */
 public class FunctionManager {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(FunctionManager.class);
@@ -52,21 +50,16 @@ public class FunctionManager {
   private static final ThreadLocal<WeakHashMap<Class<? extends RayFunc>, JavaFunctionDescriptor>>
       RAY_FUNC_CACHE = ThreadLocal.withInitial(WeakHashMap::new);
 
-  /**
-   * Mapping from the job id to the functions that belong to this job.
-   */
+  /** Mapping from the job id to the functions that belong to this job. */
   private ConcurrentMap<JobId, JobFunctionTable> jobFunctionTables = new ConcurrentHashMap<>();
 
-  /**
-   * The resource path which we can load the job's jar resources.
-   */
+  /** The resource path which we can load the job's jar resources. */
   private final List<String> codeSearchPath;
 
   /**
    * Construct a FunctionManager with the specified code search path.
    *
-   * @param codeSearchPath The specified job resource that can store the job's
-   *                        resources.
+   * @param codeSearchPath The specified job resource that can store the job's resources.
    */
   public FunctionManager(List<String> codeSearchPath) {
     this.codeSearchPath = codeSearchPath;
@@ -76,8 +69,7 @@ public class FunctionManager {
    * Get the RayFunction from a RayFunc instance (a lambda).
    *
    * @param jobId current job id.
-   * @param func  The lambda.
-   * @return A RayFunction object.
+   * @param func The lambda. Returns A RayFunction object.
    */
   public RayFunction getFunction(JobId jobId, RayFunc func) {
     JavaFunctionDescriptor functionDescriptor = RAY_FUNC_CACHE.get().get(func.getClass());
@@ -98,11 +90,9 @@ public class FunctionManager {
    * Get the RayFunction from a function descriptor.
    *
    * @param jobId Current job id.
-   * @param functionDescriptor The function descriptor.
-   * @return A RayFunction object.
+   * @param functionDescriptor The function descriptor. Returns A RayFunction object.
    */
-  public RayFunction getFunction(JobId jobId,
-                                 JavaFunctionDescriptor functionDescriptor) {
+  public RayFunction getFunction(JobId jobId, JavaFunctionDescriptor functionDescriptor) {
     JobFunctionTable jobFunctionTable = jobFunctionTables.get(jobId);
     if (jobFunctionTable == null) {
       synchronized (this) {
@@ -121,21 +111,27 @@ public class FunctionManager {
     if (codeSearchPath == null || codeSearchPath.isEmpty()) {
       classLoader = getClass().getClassLoader();
     } else {
-      URL[] urls = codeSearchPath.stream()
+      URL[] urls =
+          codeSearchPath.stream()
               .filter(p -> StringUtils.isNotBlank(p) && Files.exists(Paths.get(p)))
-          .flatMap(p -> {
+              .flatMap(
+                  p -> {
                     try {
                       if (!Files.isDirectory(Paths.get(p))) {
                         if (!p.endsWith(".jar")) {
-                  return Stream.of(Paths.get(p).getParent().toAbsolutePath().toUri().toURL());
+                          return Stream.of(
+                              Paths.get(p).getParent().toAbsolutePath().toUri().toURL());
                         } else {
                           return Stream.of(Paths.get(p).toAbsolutePath().toUri().toURL());
                         }
                       } else {
                         List<URL> subUrls = new ArrayList<>();
                         subUrls.add(Paths.get(p).toAbsolutePath().toUri().toURL());
-                Collection<File> jars = FileUtils.listFiles(new File(p),
-                    new RegexFileFilter(".*\\.jar"), DirectoryFileFilter.DIRECTORY);
+                        Collection<File> jars =
+                            FileUtils.listFiles(
+                                new File(p),
+                                new RegexFileFilter(".*\\.jar"),
+                                DirectoryFileFilter.DIRECTORY);
                         for (File jar : jars) {
                           subUrls.add(jar.toPath().toUri().toURL());
                         }
@@ -144,7 +140,8 @@ public class FunctionManager {
                     } catch (MalformedURLException e) {
                       throw new RuntimeException(String.format("Illegal %s resource path", p));
                     }
-          }).toArray(URL[]::new);
+                  })
+              .toArray(URL[]::new);
       classLoader = new URLClassLoader(urls);
       LOGGER.debug("Resource loaded for job {} from path {}.", jobId, urls);
     }
@@ -152,18 +149,12 @@ public class FunctionManager {
     return new JobFunctionTable(classLoader);
   }
 
-  /**
-   * Manages all functions that belong to one job.
-   */
+  /** Manages all functions that belong to one job. */
   static class JobFunctionTable {
 
-    /**
-     * The job's corresponding class loader.
-     */
+    /** The job's corresponding class loader. */
     final ClassLoader classLoader;
-    /**
-     * Functions per class, per function name + type descriptor.
-     */
+    /** Functions per class, per function name + type descriptor. */
     ConcurrentMap<String, Map<Pair<String, String>, RayFunction>> functions;
 
     JobFunctionTable(ClassLoader classLoader) {
@@ -187,7 +178,8 @@ public class FunctionManager {
       if (func == null) {
         if (classFunctions.containsKey(key)) {
           throw new RuntimeException(
-                  String.format("RayFunction %s is overloaded, the signature can't be empty.",
+              String.format(
+                  "RayFunction %s is overloaded, the signature can't be empty.",
                   descriptor.toString()));
         } else {
           throw new RuntimeException(
@@ -197,9 +189,7 @@ public class FunctionManager {
       return func;
     }
 
-    /**
-     * Load all functions from a class.
-     */
+    /** Load all functions from a class. */
     Map<Pair<String, String>, RayFunction> loadFunctionsForClass(String className) {
       // If RayFunction is null, the function is overloaded.
       Map<Pair<String, String>, RayFunction> map = new HashMap<>();
@@ -232,8 +222,9 @@ public class FunctionManager {
           final Type type =
               e instanceof Method ? Type.getType((Method) e) : Type.getType((Constructor) e);
           final String signature = type.getDescriptor();
-          RayFunction rayFunction = new RayFunction(e, classLoader,
-              new JavaFunctionDescriptor(className, methodName, signature));
+          RayFunction rayFunction =
+              new RayFunction(
+                  e, classLoader, new JavaFunctionDescriptor(className, methodName, signature));
           map.put(ImmutablePair.of(methodName, signature), rayFunction);
           // For cross language call java function without signature
           final Pair<String, String> emptyDescriptor = ImmutablePair.of(methodName, "");

java/runtime/src/main/java/io/ray/runtime/functionmanager/JavaFunctionDescriptor.java

@@ -5,22 +5,14 @@ import com.google.common.collect.ImmutableList;
 import io.ray.runtime.generated.Common.Language;
 import java.util.List;
 
-/**
- * Represents metadata of Java function.
- */
+/** Represents metadata of Java function. */
 public final class JavaFunctionDescriptor implements FunctionDescriptor {
 
-  /**
-   * Function's class name.
-   */
+  /** Function's class name. */
   public final String className;
-  /**
-   * Function's name.
-   */
+  /** Function's name. */
   public final String name;
-  /**
-   * Function's signature.
-   */
+  /** Function's signature. */
   public final String signature;
 
   public JavaFunctionDescriptor(String className, String name, String signature) {
@@ -43,9 +35,9 @@ public final class JavaFunctionDescriptor implements FunctionDescriptor {
       return false;
     }
     JavaFunctionDescriptor that = (JavaFunctionDescriptor) o;
-    return Objects.equal(className, that.className) &&
-        Objects.equal(name, that.name) &&
-        Objects.equal(signature, that.signature);
+    return Objects.equal(className, that.className)
+        && Objects.equal(name, that.name)
+        && Objects.equal(signature, that.signature);
   }
 
   @Override

java/runtime/src/main/java/io/ray/runtime/functionmanager/PyFunctionDescriptor.java

@@ -5,9 +5,7 @@ import io.ray.runtime.generated.Common.Language;
 import java.util.Arrays;
 import java.util.List;
 
-/**
- * Represents metadata of a Python function.
- */
+/** Represents metadata of a Python function. */
 public class PyFunctionDescriptor implements FunctionDescriptor {
 
   public String moduleName;
@@ -36,9 +34,9 @@ public class PyFunctionDescriptor implements FunctionDescriptor {
       return false;
     }
     PyFunctionDescriptor that = (PyFunctionDescriptor) o;
-    return Objects.equal(moduleName, that.moduleName) &&
-      Objects.equal(className, that.className) &&
-      Objects.equal(functionName, that.functionName);
+    return Objects.equal(moduleName, that.moduleName)
+        && Objects.equal(className, that.className)
+        && Objects.equal(functionName, that.functionName);
   }
 
   @Override
@@ -56,4 +54,3 @@ public class PyFunctionDescriptor implements FunctionDescriptor {
     return Language.PYTHON;
   }
 }
-

java/runtime/src/main/java/io/ray/runtime/functionmanager/RayFunction.java

@@ -5,50 +5,36 @@ import java.lang.reflect.Executable;
 import java.lang.reflect.Method;
 import java.util.Optional;
 
-/**
- * Represents a Ray function (either a Method or a Constructor in Java) and its metadata.
- */
+/** Represents a Ray function (either a Method or a Constructor in Java) and its metadata. */
 public class RayFunction {
 
-  /**
-   * The executor object, can be either a Method or a Constructor.
-   */
+  /** The executor object, can be either a Method or a Constructor. */
   public final Executable executable;
 
-  /**
-   * This function's class loader.
-   */
+  /** This function's class loader. */
   public final ClassLoader classLoader;
 
-  /**
-   * Function's metadata.
-   */
+  /** Function's metadata. */
   public final JavaFunctionDescriptor functionDescriptor;
 
-  public RayFunction(Executable executable, ClassLoader classLoader,
-      JavaFunctionDescriptor functionDescriptor) {
+  public RayFunction(
+      Executable executable, ClassLoader classLoader, JavaFunctionDescriptor functionDescriptor) {
     this.executable = executable;
     this.classLoader = classLoader;
     this.functionDescriptor = functionDescriptor;
   }
 
-  /**
-   * @return True if it's a constructor, otherwise it's a method.
-   */
+  /** Returns True if it's a constructor, otherwise it's a method. */
   public boolean isConstructor() {
     return executable instanceof Constructor;
   }
 
-  /**
-   * @return The underlying constructor object.
-   */
+  /** Returns The underlying constructor object. */
   public Constructor<?> getConstructor() {
     return (Constructor<?>) executable;
   }
 
-  /**
-   * @return The underlying method object.
-   */
+  /** Returns The underlying method object. */
   public Method getMethod() {
     return (Method) executable;
   }
@@ -57,9 +43,7 @@ public class RayFunction {
     return functionDescriptor;
   }
 
-  /**
-   * @return Whether this function has a return value.
-   */
+  /** Returns Whether this function has a return value. */
   public boolean hasReturn() {
     if (isConstructor()) {
       return true;
@@ -68,9 +52,7 @@ public class RayFunction {
     }
   }
 
-  /**
-   * @return Return type.
-   */
+  /** Returns Return type. */
   public Optional<Class<?>> getReturnType() {
     if (hasReturn()) {
       return Optional.of(((Method) executable).getReturnType());

java/runtime/src/main/java/io/ray/runtime/gcs/GcsClient.java

@@ -20,9 +20,7 @@ import org.apache.commons.lang3.ArrayUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-/**
- * An implementation of GcsClient.
- */
+/** An implementation of GcsClient. */
 public class GcsClient {
   private static Logger LOGGER = LoggerFactory.getLogger(GcsClient.class);
   private RedisClient primary;
@@ -35,9 +33,9 @@ public class GcsClient {
   }
 
   /**
-   * Get placement group by {@link PlacementGroupId}
-   * @param placementGroupId Id of placement group.
-   * @return The placement group.
+   * Get placement group by {@link PlacementGroupId}.
+   *
+   * @param placementGroupId Id of placement group. Returns The placement group.
    */
   public PlacementGroup getPlacementGroupInfo(PlacementGroupId placementGroupId) {
     byte[] result = globalStateAccessor.getPlacementGroupInfo(placementGroupId);
@@ -46,7 +44,8 @@ public class GcsClient {
 
   /**
    * Get all placement groups in this cluster.
-   * @return All placement groups.
+   *
+   * <p>Returns All placement groups.
    */
   public List<PlacementGroup> getAllPlacementGroupInfo() {
     List<byte[]> results = globalStateAccessor.getAllPlacementGroupInfo();
@@ -71,15 +70,20 @@ public class GcsClient {
       } catch (InvalidProtocolBufferException e) {
         throw new RuntimeException("Received invalid protobuf data from GCS.");
       }
-      final UniqueId nodeId = UniqueId
-          .fromByteBuffer(data.getNodeId().asReadOnlyByteBuffer());
+      final UniqueId nodeId = UniqueId.fromByteBuffer(data.getNodeId().asReadOnlyByteBuffer());
 
       // NOTE(lingxuan.zlx): we assume no duplicated node id in fetched node list
       // and it's only one final state for each node in recorded table.
-      NodeInfo nodeInfo = new NodeInfo(
-          nodeId, data.getNodeManagerAddress(), data.getNodeManagerHostname(),
-          data.getNodeManagerPort(), data.getObjectStoreSocketName(), data.getRayletSocketName(),
-          data.getState() == GcsNodeInfo.GcsNodeState.ALIVE, new HashMap<>());
+      NodeInfo nodeInfo =
+          new NodeInfo(
+              nodeId,
+              data.getNodeManagerAddress(),
+              data.getNodeManagerHostname(),
+              data.getNodeManagerPort(),
+              data.getObjectStoreSocketName(),
+              data.getRayletSocketName(),
+              data.getState() == GcsNodeInfo.GcsNodeState.ALIVE,
+              new HashMap<>());
       nodes.put(nodeId, nodeInfo);
     }
 
@@ -119,9 +123,7 @@ public class GcsClient {
     return resources;
   }
 
-  /**
-   * If the actor exists in GCS.
-   */
+  /** If the actor exists in GCS. */
   public boolean actorExists(ActorId actorId) {
     byte[] result = globalStateAccessor.getActorInfo(actorId);
     return result != null;
@@ -149,9 +151,7 @@ public class GcsClient {
     return JobId.fromInt(jobCounter);
   }
 
-  /**
-   * Destroy global state accessor when ray native runtime will be shutdown.
-   */
+  /** Destroy global state accessor when ray native runtime will be shutdown. */
   public void destroy() {
     // Only ray shutdown should call gcs client destroy.
     LOGGER.debug("Destroying global state accessor.");

java/runtime/src/main/java/io/ray/runtime/gcs/GcsClientOptions.java

@@ -3,9 +3,7 @@ package io.ray.runtime.gcs;
 import com.google.common.base.Preconditions;
 import io.ray.runtime.config.RayConfig;
 
-/**
- * Options to create GCS Client.
- */
+/** Options to create GCS Client. */
 public class GcsClientOptions {
   public String ip;
   public int port;

java/runtime/src/main/java/io/ray/runtime/gcs/GlobalStateAccessor.java

@@ -6,18 +6,15 @@ import io.ray.api.id.PlacementGroupId;
 import io.ray.api.id.UniqueId;
 import java.util.List;
 
-/**
- * `GlobalStateAccessor` is used for accessing information from GCS.
- *
- **/
+/** `GlobalStateAccessor` is used for accessing information from GCS. */
 public class GlobalStateAccessor {
   // NOTE(lingxuan.zlx): this is a singleton, it can not be changed during a Ray session.
   // Native pointer to the C++ GcsStateAccessor.
   private Long globalStateAccessorNativePointer = 0L;
   private static GlobalStateAccessor globalStateAccessor;
 
-  public static synchronized GlobalStateAccessor getInstance(String redisAddress,
-                                                             String redisPassword) {
+  public static synchronized GlobalStateAccessor getInstance(
+      String redisAddress, String redisPassword) {
     if (null == globalStateAccessor) {
       globalStateAccessor = new GlobalStateAccessor(redisAddress, redisPassword);
     }
@@ -32,8 +29,7 @@ public class GlobalStateAccessor {
   }
 
   private GlobalStateAccessor(String redisAddress, String redisPassword) {
-    globalStateAccessorNativePointer =
-      nativeCreateGlobalStateAccessor(redisAddress, redisPassword);
+    globalStateAccessorNativePointer = nativeCreateGlobalStateAccessor(redisAddress, redisPassword);
     validateGlobalStateAccessorPointer();
     connect();
   }
@@ -43,13 +39,12 @@ public class GlobalStateAccessor {
   }
 
   private void validateGlobalStateAccessorPointer() {
-    Preconditions.checkState(globalStateAccessorNativePointer != 0,
+    Preconditions.checkState(
+        globalStateAccessorNativePointer != 0,
         "Global state accessor native pointer must not be 0.");
   }
 
-  /**
-   * @return A list of job info with JobInfo protobuf schema.
-   */
+  /** Returns A list of job info with JobInfo protobuf schema. */
   public List<byte[]> getAllJobInfo() {
     // Fetch a job list with protobuf bytes format from GCS.
     synchronized (GlobalStateAccessor.class) {
@@ -58,9 +53,7 @@ public class GlobalStateAccessor {
     }
   }
 
-  /**
-   * @return A list of node info with GcsNodeInfo protobuf schema.
-   */
+  /** Returns A list of node info with GcsNodeInfo protobuf schema. */
   public List<byte[]> getAllNodeInfo() {
     // Fetch a node list with protobuf bytes format from GCS.
     synchronized (GlobalStateAccessor.class) {
@@ -70,6 +63,8 @@ public class GlobalStateAccessor {
   }
 
   /**
+   * Get node resource info.
+   *
    * @param nodeId node unique id.
    * @return A map of node resource info in protobuf schema.
    */
@@ -83,8 +78,8 @@ public class GlobalStateAccessor {
   public byte[] getPlacementGroupInfo(PlacementGroupId placementGroupId) {
     synchronized (GlobalStateAccessor.class) {
       validateGlobalStateAccessorPointer();
-      return nativeGetPlacementGroupInfo(globalStateAccessorNativePointer,
-        placementGroupId.getBytes());
+      return nativeGetPlacementGroupInfo(
+          globalStateAccessorNativePointer, placementGroupId.getBytes());
     }
   }
 
@@ -102,9 +97,7 @@ public class GlobalStateAccessor {
     }
   }
 
-  /**
-   * @return A list of actor info with ActorInfo protobuf schema.
-   */
+  /** Returns A list of actor info with ActorInfo protobuf schema. */
   public List<byte[]> getAllActorInfo() {
     // Fetch a actor list with protobuf bytes format from GCS.
     synchronized (GlobalStateAccessor.class) {
@@ -113,9 +106,7 @@ public class GlobalStateAccessor {
     }
   }
 
-  /**
-   * @return An actor info with ActorInfo protobuf schema.
-   */
+  /** Returns An actor info with ActorInfo protobuf schema. */
   public byte[] getActorInfo(ActorId actorId) {
     // Fetch an actor with protobuf bytes format from GCS.
     synchronized (GlobalStateAccessor.class) {
@@ -152,8 +143,7 @@ public class GlobalStateAccessor {
 
   private native byte[] nativeGetActorInfo(long nativePtr, byte[] actorId);
 
-  private native byte[] nativeGetPlacementGroupInfo(long nativePtr,
-      byte[] placementGroupId);
+  private native byte[] nativeGetPlacementGroupInfo(long nativePtr, byte[] placementGroupId);
 
   private native List<byte[]> nativeGetAllPlacementGroupInfo(long nativePtr);
 }

java/runtime/src/main/java/io/ray/runtime/gcs/RedisClient.java

@@ -7,9 +7,7 @@ import redis.clients.jedis.Jedis;
 import redis.clients.jedis.JedisPool;
 import redis.clients.jedis.JedisPoolConfig;
 
-/**
- * Redis client class.
- */
+/** Redis client class. */
 public class RedisClient {
 
   private static final int JEDIS_POOL_SIZE = 1;
@@ -23,19 +21,20 @@ public class RedisClient {
   public RedisClient(String redisAddress, String password) {
     String[] ipAndPort = redisAddress.split(":");
     if (ipAndPort.length != 2) {
-      throw new IllegalArgumentException("The argument redisAddress " +
-          "should be formatted as ip:port.");
+      throw new IllegalArgumentException(
+          "The argument redisAddress " + "should be formatted as ip:port.");
     }
 
     JedisPoolConfig jedisPoolConfig = new JedisPoolConfig();
     jedisPoolConfig.setMaxTotal(JEDIS_POOL_SIZE);
 
     if (Strings.isNullOrEmpty(password)) {
-      jedisPool = new JedisPool(jedisPoolConfig,
-          ipAndPort[0], Integer.parseInt(ipAndPort[1]), 30000);
+      jedisPool =
+          new JedisPool(jedisPoolConfig, ipAndPort[0], Integer.parseInt(ipAndPort[1]), 30000);
     } else {
-      jedisPool = new JedisPool(jedisPoolConfig, ipAndPort[0],
-          Integer.parseInt(ipAndPort[1]), 30000, password);
+      jedisPool =
+          new JedisPool(
+              jedisPoolConfig, ipAndPort[0], Integer.parseInt(ipAndPort[1]), 30000, password);
     }
   }
 
@@ -89,7 +88,7 @@ public class RedisClient {
   /**
    * Return the specified elements of the list stored at the specified key.
    *
-   * @return Multi bulk reply, specifically a list of elements in the specified range.
+   * <p>Returns Multi bulk reply, specifically a list of elements in the specified range.
    */
   public List<byte[]> lrange(byte[] key, long start, long end) {
     try (Jedis jedis = jedisPool.getResource()) {
@@ -97,9 +96,7 @@ public class RedisClient {
     }
   }
 
-  /**
-   * Whether the key exists in Redis.
-   */
+  /** Whether the key exists in Redis. */
   public boolean exists(byte[] key) {
     try (Jedis jedis = jedisPool.getResource()) {
       return jedis.exists(key);

java/runtime/src/main/java/io/ray/runtime/metric/Count.java

@@ -1,14 +1,11 @@
 package io.ray.runtime.metric;
 
 import com.google.common.base.Preconditions;
-
 import java.util.Map;
 import java.util.concurrent.atomic.DoubleAdder;
 import java.util.stream.Collectors;
 
-/**
- * Count measurement is mapped to count object in stats and counts the number.
- */
+/** Count measurement is mapped to count object in stats and counts the number. */
 public class Count extends Metric {
 
   private DoubleAdder count;
@@ -16,7 +13,11 @@ public class Count extends Metric {
   public Count(String name, String description, String unit, Map<TagKey, String> tags) {
     super(name, tags);
     count = new DoubleAdder();
-    metricNativePointer = NativeMetric.registerCountNative(name, description, unit,
+    metricNativePointer =
+        NativeMetric.registerCountNative(
+            name,
+            description,
+            unit,
             tags.keySet().stream().map(TagKey::getTagKey).collect(Collectors.toList()));
     Preconditions.checkState(metricNativePointer != 0, "Count native pointer must not be 0.");
   }

java/runtime/src/main/java/io/ray/runtime/metric/Gauge.java

@@ -4,15 +4,16 @@ import com.google.common.base.Preconditions;
 import java.util.Map;
 import java.util.stream.Collectors;
 
-
-/**
- * Gauge measurement is mapped to gauge object in stats and is recording the last value.
- */
+/** Gauge measurement is mapped to gauge object in stats and is recording the last value. */
 public class Gauge extends Metric {
 
   public Gauge(String name, String description, String unit, Map<TagKey, String> tags) {
     super(name, tags);
-    metricNativePointer = NativeMetric.registerGaugeNative(name, description, unit,
+    metricNativePointer =
+        NativeMetric.registerGaugeNative(
+            name,
+            description,
+            unit,
             tags.keySet().stream().map(TagKey::getTagKey).collect(Collectors.toList()));
     Preconditions.checkState(metricNativePointer != 0, "Gauge native pointer must not be 0.");
   }
@@ -31,4 +32,3 @@ public class Gauge extends Metric {
     this.value.set(value);
   }
 }
-

java/runtime/src/main/java/io/ray/runtime/metric/Histogram.java

@@ -1,7 +1,6 @@
 package io.ray.runtime.metric;
 
 import com.google.common.base.Preconditions;
-
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -9,23 +8,30 @@ import java.util.Map;
 import java.util.stream.Collectors;
 
 /**
- * Histogram measurement is mapped to histogram object in stats.
- * In order to reduce JNI calls overhead, a memory historical window is used
- * for storing transient value and we assume its max size is 100.
+ * Histogram measurement is mapped to histogram object in stats. In order to reduce JNI calls
+ * overhead, a memory historical window is used for storing transient value and we assume its max
+ * size is 100.
  */
 public class Histogram extends Metric {
 
   private List<Double> histogramWindow;
   public static final int HISTOGRAM_WINDOW_SIZE = 100;
 
-  public Histogram(String name, String description, String unit, List<Double> boundaries,
+  public Histogram(
+      String name,
+      String description,
+      String unit,
+      List<Double> boundaries,
       Map<TagKey, String> tags) {
     super(name, tags);
-    metricNativePointer = NativeMetric.registerHistogramNative(name, description, unit,
+    metricNativePointer =
+        NativeMetric.registerHistogramNative(
+            name,
+            description,
+            unit,
             boundaries.stream().mapToDouble(Double::doubleValue).toArray(),
             tags.keySet().stream().map(TagKey::getTagKey).collect(Collectors.toList()));
-    Preconditions.checkState(metricNativePointer != 0,
-        "Histogram native pointer must not be 0.");
+    Preconditions.checkState(metricNativePointer != 0, "Histogram native pointer must not be 0.");
     histogramWindow = Collections.synchronizedList(new ArrayList<>());
   }
 

java/runtime/src/main/java/io/ray/runtime/metric/Metric.java

@@ -8,8 +8,8 @@ import java.util.Map;
 import java.util.stream.Collectors;
 
 /**
- * Class metric is mapped to stats metric object in core worker.
- * it must be in categories set [Gague, Count, Sum, Histogram].
+ * Class metric is mapped to stats metric object in core worker. it must be in categories set
+ * [Gague, Count, Sum, Histogram].
  */
 public abstract class Metric {
   protected String name;
@@ -33,9 +33,7 @@ public abstract class Metric {
   // Metric data will be flushed into stats view data inside core worker immediately after
   // record is called.
 
-  /**
-   * Flush records to stats in last aggregator.
-   */
+  /** Flush records to stats in last aggregator. */
   public void record() {
     Preconditions.checkState(metricNativePointer != 0, "Metric native pointer must not be 0.");
     // Get tag key list from map;
@@ -46,20 +44,22 @@ public abstract class Metric {
       tagValues.add(entry.getValue());
     }
     // Get tag value list from map;
-    NativeMetric.recordNative(metricNativePointer, getAndReset(), nativeTagKeyList.stream()
-        .map(TagKey::getTagKey).collect(Collectors.toList()), tagValues);
+    NativeMetric.recordNative(
+        metricNativePointer,
+        getAndReset(),
+        nativeTagKeyList.stream().map(TagKey::getTagKey).collect(Collectors.toList()),
+        tagValues);
   }
 
   /**
    * Get the value to record and then reset.
    *
-   * @return latest updating value.
+   * <p>Returns latest updating value.
    */
   protected abstract double getAndReset();
 
   /**
-   * Update gauge value without tags.
-   * Update metric info for user.
+   * Update gauge value without tags. Update metric info for user.
    *
    * @param value latest value for updating
    */
@@ -76,14 +76,11 @@ public abstract class Metric {
     this.tags = tags;
   }
 
-  /**
-   * Deallocate object from stats and reset native pointer in null.
-   */
+  /** Deallocate object from stats and reset native pointer in null. */
   public void unregister() {
     if (0 != metricNativePointer) {
       NativeMetric.unregisterMetricNative(metricNativePointer);
     }
     metricNativePointer = 0;
   }
-
 }

java/runtime/src/main/java/io/ray/runtime/metric/MetricConfig.java

@@ -2,17 +2,16 @@ package io.ray.runtime.metric;
 
 import com.google.common.base.MoreObjects;
 
-/**
- * Configurations of the metric.
- */
+/** Configurations of the metric. */
 public class MetricConfig {
 
   private static final long DEFAULT_TIME_INTERVAL_MS = 5000L;
   private static final int DEFAULT_THREAD_POLL_SIZE = 1;
   private static final long DEFAULT_SHUTDOWN_WAIT_TIME_MS = 3000L;
 
-  public static final MetricConfig DEFAULT_CONFIG = new MetricConfig(DEFAULT_TIME_INTERVAL_MS,
-      DEFAULT_THREAD_POLL_SIZE, DEFAULT_SHUTDOWN_WAIT_TIME_MS);
+  public static final MetricConfig DEFAULT_CONFIG =
+      new MetricConfig(
+          DEFAULT_TIME_INTERVAL_MS, DEFAULT_THREAD_POLL_SIZE, DEFAULT_SHUTDOWN_WAIT_TIME_MS);
 
   private final long timeIntervalMs;
   private final int threadPoolSize;
@@ -73,6 +72,4 @@ public class MetricConfig {
       return this;
     }
   }
-
-
 }

java/runtime/src/main/java/io/ray/runtime/metric/MetricId.java

@@ -5,10 +5,9 @@ import java.util.Map;
 import java.util.Objects;
 
 /**
- * MetricId represents a metric with a given type, name and tags.
- * If two metrics have the same type and name but different tags(including key and value), they have
- * a different MetricId. And in this way, {@link MetricRegistry} can register two metrics with same
- * name but different tags.
+ * MetricId represents a metric with a given type, name and tags. If two metrics have the same type
+ * and name but different tags(including key and value), they have a different MetricId. And in this
+ * way, {@link MetricRegistry} can register two metrics with same name but different tags.
  */
 public class MetricId {
 
@@ -31,9 +30,9 @@ public class MetricId {
       return false;
     }
     MetricId metricId = (MetricId) o;
-    return type == metricId.type &&
-        Objects.equals(name, metricId.name) &&
-        Objects.equals(tags, metricId.tags);
+    return type == metricId.type
+        && Objects.equals(name, metricId.name)
+        && Objects.equals(tags, metricId.tags);
   }
 
   @Override

java/runtime/src/main/java/io/ray/runtime/metric/MetricRegistry.java

@@ -9,9 +9,7 @@ import java.util.concurrent.TimeUnit;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-/**
- * MetricRegistry is a registry for metrics to be registered and updates metrics.
- */
+/** MetricRegistry is a registry for metrics to be registered and updates metrics. */
 public class MetricRegistry {
 
   public static final MetricRegistry DEFAULT_REGISTRY = new MetricRegistry();
@@ -32,10 +30,15 @@ public class MetricRegistry {
     synchronized (this) {
       if (!isRunning) {
         this.metricConfig = metricConfig;
-        scheduledExecutorService = new ScheduledThreadPoolExecutor(metricConfig.threadPoolSize(),
+        scheduledExecutorService =
+            new ScheduledThreadPoolExecutor(
+                metricConfig.threadPoolSize(),
                 new ThreadFactoryBuilder().setNameFormat("metric-registry-%d").build());
-        scheduledExecutorService.scheduleAtFixedRate(this::update, metricConfig.timeIntervalMs(),
-            metricConfig.timeIntervalMs(), TimeUnit.MILLISECONDS);
+        scheduledExecutorService.scheduleAtFixedRate(
+            this::update,
+            metricConfig.timeIntervalMs(),
+            metricConfig.timeIntervalMs(),
+            TimeUnit.MILLISECONDS);
         isRunning = true;
         LOG.info("Finished startup metric registry, metricConfig is {}.", metricConfig);
       }
@@ -47,15 +50,18 @@ public class MetricRegistry {
       if (isRunning && scheduledExecutorService != null) {
         try {
           scheduledExecutorService.shutdownNow();
-          if (!scheduledExecutorService.awaitTermination(metricConfig.shutdownWaitTimeMs(),
-              TimeUnit.MILLISECONDS)) {
-            LOG.warn("Metric registry did not shut down in {}ms time, so try to shut down again.",
+          if (!scheduledExecutorService.awaitTermination(
+              metricConfig.shutdownWaitTimeMs(), TimeUnit.MILLISECONDS)) {
+            LOG.warn(
+                "Metric registry did not shut down in {}ms time, so try to shut down again.",
                 metricConfig.shutdownWaitTimeMs());
             scheduledExecutorService.shutdownNow();
           }
         } catch (InterruptedException e) {
-          LOG.warn("Interrupted when shutting down metric registry, so try to shut down again.",
-              e.getMessage(), e);
+          LOG.warn(
+              "Interrupted when shutting down metric registry, so try to shut down again.",
+              e.getMessage(),
+              e);
           scheduledExecutorService.shutdownNow();
         }
         if (scheduledExecutorService.isShutdown()) {
@@ -106,7 +112,8 @@ public class MetricRegistry {
   }
 
   private void update() {
-    registeredMetrics.forEach((id, metric) -> {
+    registeredMetrics.forEach(
+        (id, metric) -> {
           metric.record();
         });
   }
@@ -131,5 +138,4 @@ public class MetricRegistry {
   private MetricId genMetricIdByMetric(Metric metric) {
     return new MetricId(getMetricType(metric), metric.name, metric.tags);
   }
-
 }