多线程-----------lock condirion reentrantlock reentrantreadwritelock

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多线程-----------lock condirion reentrantlock reentrantreadwritelock

1.同步锁 ：synchronized 修饰锁 ，在方法名前 加上 或者使用synchronized的对象锁
lock
2.lock 的wait 与 noyify
使用 condition

 Condition cona =lock.newCondition();//同步监视器

 public void sleepabya() {
		  lock.lock();
		  try{
			  System.out.println("i will do await by cona");
			  cona.await();
			 System.out.println("now i have get the signal! ");
			  
			  
		  }
		  catch(Exception e) {
			  
		  }
		  finally {
			  lock.unlock();
		  }
		  
		  
	  }

 public void notifyitbya() {//必须在condition.await()方法调用之前调用lock.lock()代码获得同步监视器，不然会报错。
		  lock.lock();
		  try{
		  System.out.println("i will signal it  by a");
		  cona.signal();
		  System.out.println("ok, i do it from a");}
		  finally {
			  lock.unlock();
		  }
	  }

3.读写锁
reentrantreadwritelock

读读是共享的，但是 写写，读写 ，写读是互斥的

import java.util.concurrent.locks.ReentrantReadWriteLock;

/**
 * 
 */

/***
 * @author 18071
 * @Date 2019年2月23日
 * 功能:  读写锁 
 ***/
public class test {
	
	
	
	public static void main(String args[]) {
       service s =new service();
        Thread a=new Thread(new threadA(s));
        Thread b=new Thread(new threadB(s));
        a.start();
        try {
			a.sleep(1000);
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
        b.start();
        
		
	}
	

}

class service{
	ReentrantReadWriteLock  rwlock=new ReentrantReadWriteLock();
	
	public void read() {
		
		rwlock.readLock().lock();
		try {
			System.out.println("我获取到了  read 锁   -by "+ Thread.currentThread().getName());
			Thread.sleep(1000);
			
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		finally {
			
		}
		
		
	}
	
public void write() {
		
		rwlock.writeLock().lock();
		try {
			System.out.println("我获取到了  write 锁   -by "+ Thread.currentThread().getName());
			//Thread.sleep(1000);
			
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		finally {
			
		}
		
		
	}
}


class threadA  implements Runnable {
	private service s=new service();
	
	threadA(service s){
		this.s=s;
		
	}
	/* (non-Javadoc)
	 * @see java.lang.Runnable#run()
	 */
	@Override
	public void run() {
		// TODO Auto-generated method stub
		s.read();
	}
	
	
}

class threadB  implements Runnable {
	private service s=new service();

	threadB(service s){
		this.s=s;
		
	}
	/* (non-Javadoc)
	 * @see java.lang.Runnable#run()
	 */
	@Override
	public void run() {
		// TODO Auto-generated method stub
		s.read();
	}
	
	
}