死锁的实现

死锁：就是当程序拿着锁A的时候再想拿锁B去做一些事情，在没拿到锁B之前这个锁B被另外一个线程拿去了，另外一个线程拿到B再想拿锁A去做事情。但是线程1没有释放锁A，所以线程2一直不能继续做事情，就释放不了锁B导致线程1也无法继续进行下面的事情。所以形成了死锁。

死锁必须是多线程的。

public class DealLockDemo implements Runnable{
   private boolean flag ;
   private static final Object locka = new Object();
   private static final Object lockb = new Object();

   public DealLockDemo(boolean flag){
       this.flag = flag;
   }

   @Override
   public void run() {
       // TODO Auto-generated method stub
       if(flag){
           synchronized(locka)
           {
               System.out.println(Thread.currentThread().getName()+" .. if locka");
               synchronized(lockb){
                   System.out.println(Thread.currentThread().getName()+".. if lockb");
               }
           }
       }else{
           synchronized(lockb){
               System.out.println(Thread.currentThread().getName()+".. else lockb");
               synchronized (locka) {
                   System.out.println(Thread.currentThread().getName() + ".. else locka");
               }
           }
       }

   }

}

这个是调用类：

public class RunDealLock {
       public static void main(String[] args) {
           DealLockDemo dealLockDemo = new DealLockDemo(true);
       DealLockDemo dealLockDemo2 = new DealLockDemo(false);

       Thread thread = new Thread(dealLockDemo);
       Thread thread2 = new Thread(dealLockDemo2);
       thread.start();
       thread2.start();
       }

}

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