LinkedList实现BlockingQueue

package com.bjsxt.base.conn009;

import java.util.LinkedList;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;

public class MyQueue {

   //1 需要一个承装元素的集合
   private LinkedList<Object> list = new LinkedList<Object>();

   //2 需要一个计数器
   private AtomicInteger count = new AtomicInteger(0);

   //3 需要制定上限和下限
   private final int minSize = 0;

   private final int maxSize ;

   //4 构造方法
   public MyQueue(int size){
       this.maxSize = size;
   }

   //5 初始化一个对象用于加锁
   private final Object lock = new Object();


// put(anObject): 把anObject加到BlockingQueue里,
//   如果BlockQueue没有空间,则调用此方法的线程被阻断，
//   直到BlockingQueue里面有空间再继续.
   public void put(Object obj){
       synchronized (lock) {
           while(count.get() == this.maxSize){
               try {
                   lock.wait();
               } catch (InterruptedException e) {
                   e.printStackTrace();
               }
           }
           //1 加入元素
           list.add(obj);
           //2 计数器累加
           count.incrementAndGet();
           //3 通知另外一个线程（唤醒）
           lock.notify();
           System.out.println("新加入的元素为:" + obj);
       }
   }


   //take: 取走BlockingQueue里排在首位的对象,若BlockingQueue为空,阻断进入等待状态直到BlockingQueue有新的数据被加入.
   public Object take(){
       Object ret = null;
       synchronized (lock) {
           while(count.get() == this.minSize){
               try {
                   lock.wait();
               } catch (InterruptedException e) {
                   e.printStackTrace();
               }
           }
           //1 做移除元素操作
           ret = list.removeFirst();
           //2 计数器递减
           count.decrementAndGet();
           //3 唤醒另外一个线程
           lock.notify();
       }
       return ret;
   }

   public int getSize(){
       return this.count.get();
   }


   public static void main(String[] args) {

       final MyQueue mq = new MyQueue(5);//队长为5
       mq.put("a");
       mq.put("b");
       mq.put("c");
       mq.put("d");
       mq.put("e");

       System.out.println("当前容器的长度:" + mq.getSize());

       Thread t1 = new Thread(new Runnable() {
           @Override
           public void run() {
               mq.put("f");
               mq.put("g");
           }
       },"t1");

       t1.start();


       Thread t2 = new Thread(new Runnable() {
           @Override
           public void run() {
               Object o1 = mq.take();
               System.out.println("移除的元素为:" + o1);
               Object o2 = mq.take();
               System.out.println("移除的元素为:" + o2);
           }
       },"t2");


       try {
           TimeUnit.SECONDS.sleep(2);
       } catch (InterruptedException e) {
           e.printStackTrace();
       }

       t2.start();


   }



}

LinkedList实现BlockingQueue

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