[Javadocs] add to o.o.cluster (#3170) (#3178)

Adds javadocs to classes in the o.o.cluster package.

Signed-off-by: Nicholas Walter Knize <nknize@apache.org>

server/src/main/java/org/opensearch/cluster/AbstractDiffable.java

@@ -41,6 +41,8 @@
 /**
  * Abstract diffable object with simple diffs implementation that sends the entire object if object has changed or
  * nothing if object remained the same.
+ *
+ * @opensearch.internal
  */
 public abstract class AbstractDiffable<T extends Diffable<T>> implements Diffable<T> {
 

server/src/main/java/org/opensearch/cluster/AbstractNamedDiffable.java

@@ -43,6 +43,8 @@
 /**
  * Abstract diffable object with simple diffs implementation that sends the entire object if object has changed or
  * nothing is object remained the same. Comparing to AbstractDiffable, this class also works with NamedWriteables
+ *
+ * @opensearch.internal
  */
 public abstract class AbstractNamedDiffable<T extends NamedDiffable<T>> implements Diffable<T>, NamedWriteable {
 

server/src/main/java/org/opensearch/cluster/AckedClusterStateTaskListener.java

@@ -35,6 +35,11 @@
 import org.opensearch.common.Nullable;
 import org.opensearch.common.unit.TimeValue;
 
+/**
+ * Listener when cluster state task is acknowledged
+ *
+ * @opensearch.internal
+ */
 public interface AckedClusterStateTaskListener extends ClusterStateTaskListener {
 
     /**

server/src/main/java/org/opensearch/cluster/AckedClusterStateUpdateTask.java

@@ -41,6 +41,8 @@
 /**
  * An extension interface to {@link ClusterStateUpdateTask} that allows to be notified when
  * all the nodes have acknowledged a cluster state update request
+ *
+ * @opensearch.internal
  */
 public abstract class AckedClusterStateUpdateTask<Response> extends ClusterStateUpdateTask implements AckedClusterStateTaskListener {
 

server/src/main/java/org/opensearch/cluster/ClusterChangedEvent.java

@@ -53,6 +53,8 @@
 
 /**
  * An event received by the local node, signaling that the cluster state has changed.
+ *
+ * @opensearch.internal
  */
 public class ClusterChangedEvent {
 

server/src/main/java/org/opensearch/cluster/ClusterInfo.java

@@ -55,6 +55,8 @@
  * and a map of shard ids to shard sizes, see
  * <code>InternalClusterInfoService.shardIdentifierFromRouting(String)</code>
  * for the key used in the shardSizes map
+ *
+ * @opensearch.internal
  */
 public class ClusterInfo implements ToXContentFragment, Writeable {
     private final ImmutableOpenMap<String, DiskUsage> leastAvailableSpaceUsage;

server/src/main/java/org/opensearch/cluster/ClusterInfoService.java

@@ -36,6 +36,8 @@
 
 /**
  * Interface for a class used to gather information about a cluster periodically.
+ *
+ * @opensearch.internal
  */
 @FunctionalInterface
 public interface ClusterInfoService {

server/src/main/java/org/opensearch/cluster/ClusterModule.java

@@ -110,6 +110,8 @@
 
 /**
  * Configures classes and services that affect the entire cluster.
+ *
+ * @opensearch.internal
  */
 public class ClusterModule extends AbstractModule {
 

server/src/main/java/org/opensearch/cluster/ClusterName.java

@@ -42,6 +42,11 @@
 import java.util.Objects;
 import java.util.function.Predicate;
 
+/**
+ * Cluster Name
+ *
+ * @opensearch.internal
+ */
 public class ClusterName implements Writeable {
 
     public static final Setting<ClusterName> CLUSTER_NAME_SETTING = new Setting<>("cluster.name", "opensearch", (s) -> {

server/src/main/java/org/opensearch/cluster/ClusterState.java

@@ -97,6 +97,8 @@
  * make sure that the correct diffs are applied. If uuids don’t match, the {@link ClusterStateDiff#apply} method
  * throws the {@link IncompatibleClusterStateVersionException}, which causes the publishing mechanism to send
  * a full version of the cluster state to the node on which this exception was thrown.
+ *
+ * @opensearch.internal
  */
 public class ClusterState implements ToXContentFragment, Diffable<ClusterState> {
 

server/src/main/java/org/opensearch/cluster/ClusterStateApplier.java

@@ -37,6 +37,8 @@
 /**
  * A component that is in charge of applying an incoming cluster state to the node internal data structures.
  * The single apply method is called before the cluster state becomes visible via {@link ClusterService#state()}.
+ *
+ * @opensearch.internal
  */
 public interface ClusterStateApplier {
 

server/src/main/java/org/opensearch/cluster/ClusterStateListener.java

@@ -35,7 +35,7 @@
 /**
  * A listener to be notified when a cluster state changes.
  *
- *
+ * @opensearch.internal
  */
 public interface ClusterStateListener {
 

server/src/main/java/org/opensearch/cluster/ClusterStateObserver.java

@@ -50,6 +50,8 @@
  * A utility class which simplifies interacting with the cluster state in cases where
  * one tries to take action based on the current state but may want to wait for a new state
  * and retry upon failure.
+ *
+ * @opensearch.internal
  */
 public class ClusterStateObserver {
 

server/src/main/java/org/opensearch/cluster/ClusterStateTaskConfig.java

@@ -37,6 +37,8 @@
 
 /**
  * Cluster state update task configuration for timeout and priority
+ *
+ * @opensearch.internal
  */
 public interface ClusterStateTaskConfig {
     /**

server/src/main/java/org/opensearch/cluster/ClusterStateTaskExecutor.java

@@ -37,6 +37,11 @@
 import java.util.List;
 import java.util.Map;
 
+/**
+ * Interface that updates the cluster state based on the task
+ *
+ * @opensearch.internal
+ */
 public interface ClusterStateTaskExecutor<T> {
     /**
      * Update the cluster state based on the current state and the given tasks. Return the *same instance* if no state

server/src/main/java/org/opensearch/cluster/ClusterStateTaskListener.java

@@ -35,6 +35,11 @@
 
 import java.util.List;
 
+/**
+ * Interface to implement a cluster state change listener
+ *
+ * @opensearch.internal
+ */
 public interface ClusterStateTaskListener {
 
     /**

server/src/main/java/org/opensearch/cluster/ClusterStateUpdateTask.java

@@ -40,6 +40,8 @@
 
 /**
  * A task that can update the cluster state.
+ *
+ * @opensearch.internal
  */
 public abstract class ClusterStateUpdateTask
     implements

server/src/main/java/org/opensearch/cluster/Diff.java

@@ -36,6 +36,8 @@
 
 /**
  * Represents difference between states of cluster state parts
+ *
+ * @opensearch.internal
  */
 public interface Diff<T> extends Writeable {
 

server/src/main/java/org/opensearch/cluster/Diffable.java

@@ -36,6 +36,8 @@
 
 /**
  * Cluster state part, changes in which can be serialized
+ *
+ * @opensearch.internal
  */
 public interface Diffable<T> extends Writeable {
 

server/src/main/java/org/opensearch/cluster/DiffableUtils.java

@@ -53,6 +53,11 @@
 import java.util.Map;
 import java.util.Set;
 
+/**
+ * Utility class for a diffable
+ *
+ * @opensearch.internal
+ */
 public final class DiffableUtils {
     private DiffableUtils() {}
 

server/src/main/java/org/opensearch/cluster/DiskUsage.java

@@ -45,6 +45,8 @@
 
 /**
  * Encapsulation class used to represent the amount of disk used on a node.
+ *
+ * @opensearch.internal
  */
 public class DiskUsage implements ToXContentFragment, Writeable {
     final String nodeId;

server/src/main/java/org/opensearch/cluster/EmptyClusterInfoService.java

@@ -36,6 +36,8 @@
 
 /**
  * {@link ClusterInfoService} that provides empty maps for disk usage and shard sizes
+ *
+ * @opensearch.internal
  */
 public class EmptyClusterInfoService implements ClusterInfoService {
     public static final EmptyClusterInfoService INSTANCE = new EmptyClusterInfoService();

server/src/main/java/org/opensearch/cluster/IncompatibleClusterStateVersionException.java

@@ -39,6 +39,8 @@
 
 /**
  * Thrown by {@link Diff#apply} method
+ *
+ * @opensearch.internal
  */
 public class IncompatibleClusterStateVersionException extends OpenSearchException {
     public IncompatibleClusterStateVersionException(String msg) {

server/src/main/java/org/opensearch/cluster/InternalClusterInfoService.java

@@ -83,6 +83,8 @@
  *
  * Every time the timer runs, gathers information about the disk usage and
  * shard sizes across the cluster.
+ *
+ * @opensearch.internal
  */
 public class InternalClusterInfoService implements ClusterInfoService, ClusterStateListener {
 

server/src/main/java/org/opensearch/cluster/LocalClusterUpdateTask.java

@@ -38,7 +38,9 @@
 import java.util.List;
 
 /**
- * Used to apply state updates on nodes that are not necessarily master
+ * Used to apply state updates on nodes that are not necessarily cluster-manager
+ *
+ * @opensearch.internal
  */
 public abstract class LocalClusterUpdateTask
     implements

server/src/main/java/org/opensearch/cluster/LocalNodeMasterListener.java

@@ -32,8 +32,10 @@
 package org.opensearch.cluster;
 
 /**
- * Enables listening to master changes events of the local node (when the local node becomes the master, and when the local
- * node cease being a master).
+ * Enables listening to cluster-manager changes events of the local node (when the local node becomes the cluster-manager, and when the local
+ * node cease being a cluster-manager).
+ *
+ * @opensearch.internal
  */
 public interface LocalNodeMasterListener extends ClusterStateListener {
 

server/src/main/java/org/opensearch/cluster/MasterNodeChangePredicate.java

@@ -36,6 +36,11 @@
 
 import java.util.function.Predicate;
 
+/**
+ * Utility class to build a predicate that accepts cluster state changes
+ *
+ * @opensearch.internal
+ */
 public final class MasterNodeChangePredicate {
 
     private MasterNodeChangePredicate() {

server/src/main/java/org/opensearch/cluster/MergableCustomMetadata.java

@@ -40,6 +40,8 @@
  * Custom metadata can be merged using {@link #merge(Metadata.Custom)}.
  *
  * @param <T> type of custom meta data
+ *
+ * @opensearch.internal
  */
 public interface MergableCustomMetadata<T extends Metadata.Custom> {
 

server/src/main/java/org/opensearch/cluster/NamedDiff.java

@@ -37,6 +37,8 @@
 
 /**
  * Diff that also support NamedWriteable interface
+ *
+ * @opensearch.internal
  */
 public interface NamedDiff<T extends Diffable<T>> extends Diff<T>, NamedWriteable {
     /**

server/src/main/java/org/opensearch/cluster/NamedDiffable.java

@@ -36,5 +36,7 @@
 
 /**
  * Diff that also support {@link VersionedNamedWriteable} interface
+ *
+ * @opensearch.internal
  */
 public interface NamedDiffable<T> extends Diffable<T>, VersionedNamedWriteable {}

server/src/main/java/org/opensearch/cluster/NamedDiffableValueSerializer.java

@@ -39,6 +39,8 @@
 
 /**
  * Value Serializer for named diffables
+ *
+ * @opensearch.internal
  */
 public class NamedDiffableValueSerializer<T extends NamedDiffable<T>> extends DiffableUtils.DiffableValueSerializer<String, T> {
 

server/src/main/java/org/opensearch/cluster/NodeConnectionsService.java

@@ -80,6 +80,8 @@
  * <p>
  * This component does not block on disconnections at all, because a disconnection might need to wait for an ongoing (background) connection
  * attempt to complete first.
+ *
+ * @opensearch.internal
  */
 public class NodeConnectionsService extends AbstractLifecycleComponent {
     private static final Logger logger = LogManager.getLogger(NodeConnectionsService.class);

server/src/main/java/org/opensearch/cluster/NotMasterException.java

@@ -37,9 +37,11 @@
 import java.io.IOException;
 
 /**
- * Thrown when a node join request or a master ping reaches a node which is not
- * currently acting as a master or when a cluster state update task is to be executed
- * on a node that is no longer master.
+ * Thrown when a node join request or a cluster-manager ping reaches a node which is not
+ * currently acting as a cluster-manager or when a cluster state update task is to be executed
+ * on a node that is no longer cluster-manager.
+ *
+ * @opensearch.internal
  */
 public class NotMasterException extends OpenSearchException {
 

server/src/main/java/org/opensearch/cluster/RepositoryCleanupInProgress.java

@@ -45,6 +45,11 @@
 import java.util.Collections;
 import java.util.List;
 
+/**
+ * Information passed during repository cleanup
+ *
+ * @opensearch.internal
+ */
 public final class RepositoryCleanupInProgress extends AbstractNamedDiffable<ClusterState.Custom> implements ClusterState.Custom {
 
     public static final RepositoryCleanupInProgress EMPTY = new RepositoryCleanupInProgress(Collections.emptyList());

server/src/main/java/org/opensearch/cluster/RestoreInProgress.java

@@ -54,6 +54,8 @@
 
 /**
  * Meta data about restore processes that are currently executing
+ *
+ * @opensearch.internal
  */
 public class RestoreInProgress extends AbstractNamedDiffable<Custom> implements Custom, Iterable<RestoreInProgress.Entry> {
 

server/src/main/java/org/opensearch/cluster/SnapshotDeletionsInProgress.java

@@ -57,6 +57,8 @@
 
 /**
  * A class that represents the snapshot deletions that are in progress in the cluster.
+ *
+ * @opensearch.internal
  */
 public class SnapshotDeletionsInProgress extends AbstractNamedDiffable<Custom> implements Custom {
 

server/src/main/java/org/opensearch/cluster/SnapshotsInProgress.java

@@ -71,6 +71,8 @@
 
 /**
  * Meta data about snapshots that are currently executing
+ *
+ * @opensearch.internal
  */
 public class SnapshotsInProgress extends AbstractNamedDiffable<Custom> implements Custom {
 

server/src/main/java/org/opensearch/cluster/TimeoutClusterStateListener.java

@@ -37,7 +37,7 @@
 /**
  * An exception to cluster state listener that allows for timeouts and for post added notifications.
  *
- *
+ * @opensearch.internal
  */
 public interface TimeoutClusterStateListener extends ClusterStateListener {
 

server/src/main/java/org/opensearch/cluster/ack/AckedRequest.java

@@ -36,6 +36,8 @@
 
 /**
  * Identifies a cluster state update request with acknowledgement support
+ *
+ * @opensearch.internal
  */
 public interface AckedRequest {
 

server/src/main/java/org/opensearch/cluster/ack/ClusterStateUpdateRequest.java

@@ -37,6 +37,8 @@
 /**
  * Base class to be used when needing to update the cluster state
  * Contains the basic fields that are always needed
+ *
+ * @opensearch.internal
  */
 public abstract class ClusterStateUpdateRequest<T extends ClusterStateUpdateRequest<T>> implements AckedRequest {