OperatorState.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.runtime.checkpoint;

import org.apache.flink.runtime.jobgraph.OperatorID;
import org.apache.flink.runtime.state.CompositeStateHandle;
import org.apache.flink.runtime.state.SharedStateRegistry;
import org.apache.flink.util.Preconditions;

import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Objects;

/**
 * Simple container class which contains the raw/managed/legacy operator state and key-group state handles for the sub
 * tasks of an operator.
 */
public class OperatorState implements CompositeStateHandle {

	private static final long serialVersionUID = -4845578005863201810L;

	/** id of the operator */
	private final OperatorID operatorID;

	/** handles to non-partitioned states, subtaskindex -> subtaskstate */
	private final Map<Integer, OperatorSubtaskState> operatorSubtaskStates;

	/** parallelism of the operator when it was checkpointed */
	private final int parallelism;

	/** maximum parallelism of the operator when the job was first created */
	private final int maxParallelism;

	public OperatorState(OperatorID operatorID, int parallelism, int maxParallelism) {
		Preconditions.checkArgument(
			parallelism <= maxParallelism,
			"Parallelism " + parallelism + " is not smaller or equal to max parallelism " + maxParallelism + ".");

		this.operatorID = operatorID;

		this.operatorSubtaskStates = new HashMap<>(parallelism);

		this.parallelism = parallelism;
		this.maxParallelism = maxParallelism;
	}

	public OperatorID getOperatorID() {
		return operatorID;
	}

	public void putState(int subtaskIndex, OperatorSubtaskState subtaskState) {
		Preconditions.checkNotNull(subtaskState);

		if (subtaskIndex < 0 || subtaskIndex >= parallelism) {
			throw new IndexOutOfBoundsException("The given sub task index " + subtaskIndex +
				" exceeds the maximum number of sub tasks " + operatorSubtaskStates.size());
		} else {
			operatorSubtaskStates.put(subtaskIndex, subtaskState);
		}
	}

	public OperatorSubtaskState getState(int subtaskIndex) {
		if (subtaskIndex < 0 || subtaskIndex >= parallelism) {
			throw new IndexOutOfBoundsException("The given sub task index " + subtaskIndex +
				" exceeds the maximum number of sub tasks " + operatorSubtaskStates.size());
		} else {
			return operatorSubtaskStates.get(subtaskIndex);
		}
	}

	public Collection<OperatorSubtaskState> getStates() {
		return operatorSubtaskStates.values();
	}

	public int getNumberCollectedStates() {
		return operatorSubtaskStates.size();
	}

	public int getParallelism() {
		return parallelism;
	}

	public int getMaxParallelism() {
		return maxParallelism;
	}

	public boolean hasNonPartitionedState() {
		for (OperatorSubtaskState sts : operatorSubtaskStates.values()) {
			if (sts != null && sts.getLegacyOperatorState() != null) {
				return true;
			}
		}
		return false;
	}

	@Override
	public void discardState() throws Exception {
		for (OperatorSubtaskState operatorSubtaskState : operatorSubtaskStates.values()) {
			operatorSubtaskState.discardState();
		}
	}

	@Override
	public void registerSharedStates(SharedStateRegistry sharedStateRegistry) {
		for (OperatorSubtaskState operatorSubtaskState : operatorSubtaskStates.values()) {
			operatorSubtaskState.registerSharedStates(sharedStateRegistry);
		}
	}

	@Override
	public long getStateSize() {
		long result = 0L;

		for (int i = 0; i < parallelism; i++) {
			OperatorSubtaskState operatorSubtaskState = operatorSubtaskStates.get(i);
			if (operatorSubtaskState != null) {
				result += operatorSubtaskState.getStateSize();
			}
		}

		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (obj instanceof OperatorState) {
			OperatorState other = (OperatorState) obj;

			return operatorID.equals(other.operatorID)
				&& parallelism == other.parallelism
				&& operatorSubtaskStates.equals(other.operatorSubtaskStates);
		} else {
			return false;
		}
	}

	@Override
	public int hashCode() {
		return parallelism + 31 * Objects.hash(operatorID, operatorSubtaskStates);
	}

	public Map<Integer, OperatorSubtaskState> getSubtaskStates() {
		return Collections.unmodifiableMap(operatorSubtaskStates);
	}

	@Override
	public String toString() {
		// KvStates are always null in 1.1. Don't print this as it might
		// confuse users that don't care about how we store it internally.
		return "OperatorState(" +
			"operatorID: " + operatorID +
			", parallelism: " + parallelism +
			", maxParallelism: " + maxParallelism +
			", sub task states: " + operatorSubtaskStates.size() +
			", total size (bytes): " + getStateSize() +
			')';
	}
}