java:多线程(JDK1.5的新特性互斥锁)

* 1.同步
    * 使用ReentrantLock类的lock()和unlock()方法进行同步
* 2.通信
    * 使用ReentrantLock类的newCondition()方法可以获取Condition对象
    * 需要等待的时候使用Condition的await()方法, 唤醒的时候用signal()方法
    * 不同的线程使用不同的Condition, 这样就能区分唤醒的时候找哪个线程了
 

import java.net.ConnectException;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.ReentrantLock;

public class Demo3_ReentrantLock {

	public static void main(String[] args) {
	 Printer3 p = new Printer3();
		new Thread() {
			public void run() {
				while(true) {
					try {
						p.print1();
					} catch (InterruptedException e) {
						
						e.printStackTrace();
					}
				}
			}
		}.start();
		
		new Thread() {
			public void run() {
				while(true) {
					try {
						p.print2();
					} catch (InterruptedException e) {
						
						e.printStackTrace();
					}
				}
			}
		}.start();
		
		new Thread() {
			public void run() {
				while(true) {
					try {
						p.print3();
					} catch (InterruptedException e) {
						
						e.printStackTrace();
					}
				}
			}
		}.start();
	}

}

class Printer3 {
	private ReentrantLock r=new ReentrantLock();
	private Condition c1=r.newCondition();
	private Condition c2=r.newCondition();
	private Condition c3=r.newCondition();
	
	private int flag = 1;
	public void print1() throws InterruptedException {	
		r.lock();//获取锁
			if(flag != 1) {
				c1.await();					
			}
			System.out.print(\"1\");
			System.out.print(\"2\");
			System.out.print(\"3\");
			System.out.print(\"\\r\\n\");
			flag = 2;
			c2.signal();
			r.unlock();//释放锁
		}

	
	public void print2() throws InterruptedException {
		r.lock();//获取锁
			if(flag != 2) {
				c2.await();					
			}
			System.out.print(\"4\");
			System.out.print(\"5\");
			System.out.print(\"6\");
			System.out.print(\"\\r\\n\");
			flag = 3;
			c3.signal();
		r.unlock();//释放锁
	}
	
	public void print3() throws InterruptedException {
		r.lock();//获取锁
			if(flag != 3) {
				c3.await();						
												
			}
			System.out.print(\"7\");
			System.out.print(\"8\");
			System.out.print(\"9\");

			System.out.print(\"\\r\\n\");
			flag = 1;
			c1.signal();
		r.unlock();//释放锁
	}

}