当线程池满且等待任务queue也满时，submit(task)会block的executor

BlockingSubmissionExecutor.java

package test;

import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

/**
 * 当线程池满且等待任务queue也满时，submit(task)会block的executor
 * @author pf-miles Feb 25, 2016 1:51:39 PM
 */
public class BlockingSubmissionExecutor extends ThreadPoolExecutor {

    // 由于ThreadPoolExecutor中调用了workQueue的offer方法来加入task到队列，但offer方法天生不会block，这里将offer方法重写为block的put实现
    private static final class OfferBlockingQueue<E> extends ArrayBlockingQueue<E> {

        private static final long serialVersionUID = -8186794176623972764L;

        public OfferBlockingQueue(int capacity) {
            super(capacity);
        }

        @Override
        public boolean offer(E e) {
            try {
                put(e);
                return true;
            } catch (InterruptedException ie) {
                Thread.currentThread().interrupt();
            }
            return false;
        }
    }

    public BlockingSubmissionExecutor(int corePoolSize, int maximumPoolSize, long keepAliveTime,
                                      TimeUnit unit, int taskQueueSize, ThreadFactory threadFactory) {
        super(corePoolSize, maximumPoolSize, keepAliveTime, unit, new OfferBlockingQueue<Runnable>(
            taskQueueSize), threadFactory);
    }

}