这里定义了一个有界队列 ,保证先进先出,在队列达到上限时应该阻塞,直到队列有元素被取出才能继续往里继续添加 完整代码:
package com.comic.queue;
import java.util.LinkedList;
import java.util.concurrent.atomic.AtomicInteger;
public class BoundedQueue {
// 队列的最大值
private int maxSize;
// 计数器
private AtomicInteger counter = new AtomicInteger(0);
// 数据容器
private LinkedList<Object> content = new LinkedList<Object>();
// 琐
private Object lock = new Object();
public BoundedQueue(int maxSize) {
this.maxSize = maxSize;
}
/**
* 入队列
*
* @param obj
* @throws InterruptedException
*/
public void put(Object obj) throws InterruptedException {
synchronized (lock) {
while (maxSize == counter.get()) {
System.out.println("队列已满,请等待....");
lock.wait();
}
// 添加元素,计数,唤醒线程
content.add(obj);
counter.getAndIncrement();
lock.notify();
System.out.println(obj + "入列");
}
}
/**
* 取
*
* @return
* @throws InterruptedException
*/
public Object take() throws InterruptedException {
Object obj = null;
synchronized (lock) {
while (0 == counter.get()) {
System.out.println("队列已空,请等待....");
lock.wait();
}
// 获取第一个元素,计数,唤醒线程
obj = content.get(0);
content.remove(0);
counter.decrementAndGet();
lock.notify();
}
return obj;
}
public static void main(String[] args) throws InterruptedException {
final BoundedQueue queue = new BoundedQueue(5);
queue.put("aa");
queue.put("bb");
queue.put("cc");
queue.put("dd");
queue.put("ff");
Thread t = new Thread(new Runnable() {
@Override
public void run() {
try {
queue.put("gg");
queue.put("hh");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}, "t1");
t.start();
Thread.sleep(500);
System.out.println("**********************************");
Thread t2 = new Thread(new Runnable() {
@Override
public void run() {
try {
System.out.println("take:" + queue.take());
System.out.println("take:" + queue.take());
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}, "t2");
t2.start();
}
}
控制台部分: aa入列 bb入列 cc入列 dd入列 ff入列 队列已满,请等待.... ********************************** take:aa gg入列 队列已满,请等待.... take:bb hh入列