java多线程---顺序打印ABC的三种实现---ReentrantLock方式

使用jdk1.5并发包中引入的lock方式，这种方式使用比synchronized这种方式更加灵活，也提供了在获取锁时阻塞的办法

代码如下：

package com.zcj.thread;import java.util.concurrent.locks.Condition;import java.util.concurrent.locks.ReentrantLock;public class PrintABC {    private int status =1;    private ReentrantLock lock = new ReentrantLock();    private Condition conditionA = lock.newCondition();    private Condition conditionB = lock.newCondition();    private Condition conditionC = lock.newCondition();        public void printA(){    lock.lock();    try{    if(status!=1){    conditionA.await();    }    System.out.print("A");        status=2;        conditionB.signal();    }catch(InterruptedException e){    e.printStackTrace();    }finally{    lock.unlock();    }    }    public void printB(){    lock.lock();    try{    if(status!=2){    conditionB.await();    }    System.out.print("B");        status=3;        conditionC.signal();    }catch(InterruptedException e){    e.printStackTrace();    }finally{    lock.unlock();    }    }    public void printC(){    lock.lock();    try{    if(status!=3){    conditionC.await();    }    System.out.println("C");        status=1;        conditionA.signal();    }catch(InterruptedException e){    e.printStackTrace();    }finally{    lock.unlock();    }    }        public static void main(String[] args){    PrintABC print = new PrintABC();    Thread threadA = new Thread(new RunnableA(print));    Thread threadB = new Thread(new RunnableB(print));    Thread threadC = new Thread(new RunnableC(print));    threadA.start();    threadB.start();    threadC.start();    }}class RunnableA implements Runnable{    private PrintABC print;    public RunnableA(PrintABC print) {super();this.print = print;}@Overridepublic void run() {// TODO Auto-generated method stubfor(int i=0;i<10;i++){print.printA();}}}class RunnableB implements Runnable{    private PrintABC print;    public RunnableB(PrintABC print) {super();this.print = print;}@Overridepublic void run() {// TODO Auto-generated method stubfor(int i=0;i<10;i++){print.printB();}}}class RunnableC implements Runnable{    private PrintABC print;    public RunnableC(PrintABC print) {super();this.print = print;}@Overridepublic void run() {// TODO Auto-generated method stubfor(int i=0;i<10;i++){print.printC();}}}