java BoundedExecutor

BoundedExecutor.java

package com.lavector.concurrency;

import java.util.concurrent.*;

/**
 * @author seveniu
 * @date 2017-01-09
 * @Description
 */
public class BoundedExecutor {

    public static ExecutorService getFixedExecutorService(int queueSize, int threadNum) {
        BlockingQueue<Runnable> blockingQueue;
        if (threadNum < 1) {
            throw new IllegalArgumentException("thread number is illegal : " + threadNum);
        }
        if (queueSize < 0) {
            throw new IllegalArgumentException("queue size is illegal : " + threadNum);
        }
        if (queueSize == 0) {
            blockingQueue = new SynchronousQueue<>();
        } else {
            blockingQueue = new LinkedBlockingDeque<>();
        }
        return new ThreadPoolExecutor(threadNum, threadNum,
                0L, TimeUnit.MILLISECONDS,
                blockingQueue, Executors.defaultThreadFactory(), new RejectedExecutionHandler() {
            @Override
            public void rejectedExecution(Runnable r, ThreadPoolExecutor executor) {
                if (!executor.isShutdown()) {
                    try {
                        executor.getQueue().put(r);
                    } catch (InterruptedException e) {
                        // should not be interrupted
                    }
                }
            }
        });
    }

}