org.springframework.integration.util.WhileLockedProcessor.java Source code

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Here is the source code for org.springframework.integration.util.WhileLockedProcessor.java

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/*
 * Copyright 2002-2019 the original author or authors.
 *
 * Licensed 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
 *
 *      https://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.springframework.integration.util;

import java.io.IOException;
import java.util.concurrent.locks.Lock;

import org.springframework.integration.support.locks.LockRegistry;
import org.springframework.messaging.MessagingException;

/**
 * A simple strategy callback class that allows you to provide
 * a code that needs to be executed under {@link Lock} provided by
 * {@link LockRegistry}
 * A typical usage would be to provide implementation of {@link #whileLocked()} method and
 * then call {@link #doWhileLocked()}
 *
 * @author Oleg Zhurakousky
 * @since 2.2
 *
 */
public abstract class WhileLockedProcessor {

    private final Object key;

    private final LockRegistry lockRegistry;

    public WhileLockedProcessor(LockRegistry lockRegistry, Object key) {
        this.key = key;
        this.lockRegistry = lockRegistry;
    }

    public final void doWhileLocked() throws IOException {
        Lock lock = this.lockRegistry.obtain(this.key);
        try {
            lock.lockInterruptibly();
            try {
                this.whileLocked();
            } finally {
                lock.unlock();
            }
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
            throw new MessagingException("Thread was interrupted while performing task", e);
        }
    }

    /**
     * Override this method to provide the behavior that needs to be executed
     * while under the lock.
     *
     * @throws IOException Any IOException.
     */
    protected abstract void whileLocked() throws IOException;

}