J.U.C包学习

package com.fh.interview;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.Serializable;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.AbstractQueuedSynchronizer;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;


/**
 * 同步队列测试类
 *
 * @author
 * @create 2018-06-02 上午10:58
 **/
public class Mutex implements Lock,Serializable {


    private static class Sync extends AbstractQueuedSynchronizer{
        @Override
        protected boolean tryAcquire(int arg) {
            assert arg == 1;
            if(compareAndSetState(0,1)){
             setExclusiveOwnerThread(Thread.currentThread());
             return true;
            }
            return false;
        }

        @Override
        protected boolean tryRelease(int arg) {
            assert arg == 1;
            if(getState()==0) throw new IllegalStateException();
            setExclusiveOwnerThread(null);
            setState(0);
            return true;
        }

        //是否被当前线程所独占
        @Override
        protected boolean isHeldExclusively() {
            return getState() == 1;
        }

        Condition newCondition(){
            return new ConditionObject();
        }

        private void readObject(ObjectInputStream s)throws IOException,ClassNotFoundException{
            s.defaultReadObject();
            setState(0);
        }
    }

    private final Sync sync = new Sync();

    public void lock() {
        sync.acquire(1);
    }

    public void lockInterruptibly() throws InterruptedException {
        sync.acquireInterruptibly(1);
    }

    public boolean tryLock() {
        return sync.tryAcquire(1);
    }

    public boolean tryLock(long time, TimeUnit unit) throws InterruptedException {
        return sync.tryAcquireNanos(1,unit.toNanos(time));
    }

    public void unlock() {
        sync.release(1);
    }

    public Condition newCondition() {
        return sync.newCondition();
    }
}

测试代码

package com.fh.interview;

/**
 * 测试
 *
 * @author
 * @create 2018-06-02 上午11:22
 **/
public class MutexDemo {

    private static final Mutex mutex = new Mutex();

    public static void main(String[] args) {
        for (int i =0;i<10;i++){
            Thread thread = new Thread(new Runnable() {
                @Override
                public void run() {
                    mutex.lock();
                    try {
                        Thread.sleep(3000);
                    }catch (Exception e){
                        e.printStackTrace();
                    }finally {
                        mutex.unlock();
                    }
                }
            },"hi"+i);
            thread.start();
        }
    }
}
原文地址:https://www.cnblogs.com/nihaofenghao/p/9108312.html