LinkedBlockingQueue阻塞队列offer()操作抛出中断异常

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说明

在使用LinkedBlockingQueue的offer方法时，出现了中断异常，现分析一下出现这个中断异常的原因。

会产生中断异常的Demo

import java.util.concurrent.LinkedBlockingQueue;import java.util.concurrent.TimeUnit;public class TestLinkedBlockingQueue {    public static void main(String[] args) {        LinkedBlockingQueue lbq = new LinkedBlockingQueue(3);        for(int i = 0; i < 10; i++){            try {                System.out.println(lbq);                //这里用offer方法往阻塞队列里面添加对象，此方法表示若队列满了，则等待1秒，1秒后若队列还是满的，则丢弃数据。                lbq.offer(i, 1000, TimeUnit.MILLISECONDS);            } catch (InterruptedException e) {                // TODO Auto-generated catch block                e.printStackTrace();            }            Thread.currentThread().interrupt();//如果注释掉这行代码，则此程序不会抛出异常        }    }}

LinkedBlockingQueue的offer源码方法

    public boolean offer(E e, long timeout, TimeUnit unit)        throws InterruptedException {        if (e == null) throw new NullPointerException();        long nanos = unit.toNanos(timeout);        int c = -1;        final ReentrantLock putLock = this.putLock;        final AtomicInteger count = this.count;        putLock.lockInterruptibly();        try {            while (count.get() == capacity) {                if (nanos <= 0)                    return false;                nanos = notFull.awaitNanos(nanos);            }            enqueue(new Node<E>(e));            c = count.getAndIncrement();            if (c + 1 < capacity)                notFull.signal();        } finally {            putLock.unlock();        }        if (c == 0)            signalNotEmpty();        return true;    }    //lockInterruptibly方法    public void lockInterruptibly() throws InterruptedException {        sync.acquireInterruptibly(1);    }    //acquireInterruptibly方法        public final void acquireInterruptibly(int arg)            throws InterruptedException {        if (Thread.interrupted())            throw new InterruptedException();        if (!tryAcquire(arg))            doAcquireInterruptibly(arg);    }

所以，当线程被标记有中断标志时，offer添加时将获取不到锁，直接抛出中断异常。

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