ScheduledThreadPoolExecutor.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.tomcat.util.threads;

import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

/**
 * Class which wraps a ScheduledExecutorService, while preventing
 * lifecycle and configuration operations.
 */
public class ScheduledThreadPoolExecutor implements ScheduledExecutorService {

    protected final ScheduledExecutorService executor;

    /**
     * Builds a wrapper for the given executor.
     * @param executor the wrapped executor
     */
    public ScheduledThreadPoolExecutor(ScheduledExecutorService executor) {
        this.executor = executor;
    }

    @Override
    public void shutdown() {
        // Do nothing
    }


    @Override
    public List<Runnable> shutdownNow() {
        return Collections.emptyList();
    }

    @Override
    public boolean isShutdown() {
        return executor.isShutdown();
    }

    @Override
    public boolean isTerminated() {
        return executor.isTerminated();
    }

    @Override
    public boolean awaitTermination(long timeout, TimeUnit unit)
            throws InterruptedException {
        return executor.awaitTermination(timeout, unit);
    }

    @Override
    public <T> Future<T> submit(Callable<T> task) {
        return executor.submit(task);
    }

    @Override
    public <T> Future<T> submit(Runnable task, T result) {
        return executor.submit(task, result);
    }

    @Override
    public Future<?> submit(Runnable task) {
        return executor.submit(task);
    }

    @Override
    public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks)
            throws InterruptedException {
        return executor.invokeAll(tasks);
    }

    @Override
    public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks, long timeout,
            TimeUnit unit) throws InterruptedException {
        return executor.invokeAll(tasks, timeout, unit);
    }

    @Override
    public <T> T invokeAny(Collection<? extends Callable<T>> tasks)
            throws InterruptedException, ExecutionException {
        return executor.invokeAny(tasks);
    }

    @Override
    public <T> T invokeAny(Collection<? extends Callable<T>> tasks,
            long timeout, TimeUnit unit)
            throws InterruptedException, ExecutionException, TimeoutException {
        return executor.invokeAny(tasks, timeout, unit);
    }

    @Override
    public void execute(Runnable command) {
        executor.execute(command);
    }

    @Override
    public ScheduledFuture<?> schedule(Runnable command, long delay,
            TimeUnit unit) {
        return executor.schedule(command, delay, unit);
    }

    @Override
    public <V> ScheduledFuture<V> schedule(Callable<V> callable, long delay,
            TimeUnit unit) {
        return executor.schedule(callable, delay, unit);
    }

    @Override
    public ScheduledFuture<?> scheduleAtFixedRate(Runnable command,
            long initialDelay, long period, TimeUnit unit) {
        return executor.scheduleAtFixedRate(command, initialDelay, period, unit);
    }

    @Override
    public ScheduledFuture<?> scheduleWithFixedDelay(Runnable command,
            long initialDelay, long delay, TimeUnit unit) {
        return executor.scheduleWithFixedDelay(command, initialDelay, delay, unit);
    }

}