ThreadPoolManager.java

/*
 * Copyright 2014 jts
 *
 * 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
 *
 * 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 ru.jts.common.threading;

import java.util.concurrent.*;

/**
 * @author : Camelion
 * @date : 15.08.12  14:04
 */
public class ThreadPoolManager {
	private static final long MAX_DELAY = TimeUnit.NANOSECONDS.toMillis(Long.MAX_VALUE - System.nanoTime()) / 2;
	private boolean initied = false;

	private ScheduledThreadPoolExecutor scheduledExecutor;
	private ThreadPoolExecutor executor;

	private static ThreadPoolManager ourInstance = new ThreadPoolManager();

	public static ThreadPoolManager getInstance() {
		return ourInstance;
	}

	private ThreadPoolManager() {
	}

	public void init(int scheduledThreadPoolSize, int executorThreadPoolSize) {
		if (!initied) {
			scheduledExecutor = new ScheduledThreadPoolExecutor(scheduledThreadPoolSize);
			executor = new ThreadPoolExecutor(executorThreadPoolSize, Integer.MAX_VALUE, 5L, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>());
			initied = true;
		}
	}

	private static long validate(long delay) {
		return Math.max(0, Math.min(MAX_DELAY, delay));
	}

	public ScheduledFuture<?> schedule(Runnable r, long delay) {
		if (!initied)
			throw new IllegalStateException("ThreadPoolManager schedule() called, but manager is not initialized");
		return scheduledExecutor.schedule(r, validate(delay), TimeUnit.MILLISECONDS);
	}

	public ScheduledFuture<?> scheduleAtFixedRate(Runnable r, long initial, long delay) {
		if (!initied)
			throw new IllegalStateException("ThreadPoolManager scheduleAtFixedRate() called, but manager is not initialized");
		return scheduledExecutor.scheduleAtFixedRate(r, validate(initial), validate(delay), TimeUnit.MILLISECONDS);
	}

	public void execute(Runnable r) {
		if (!initied)
			throw new IllegalStateException("ThreadPoolManager execute() called, but manager is not initialized");
		executor.execute(r);
	}
}