理解notify与wait在线程里面的使用
public class MultiThread {
?/**
? * @param args
? */
?public static void main(String[] args) {
??// TODO Auto-generated method stub 8
??new Thread(new Thread1()).start();
??try {
???Thread.sleep(1000);
??} catch (InterruptedException e) {
???// TODO Auto-generated catch block
???e.printStackTrace();
??}
??new Thread(new Thread2()).start();??
?}
?
?
?private static class Thread1 implements Runnable
?{
??
??public void run() {
???// TODO Auto-generated method stub
//由于这里的Thread1和下面的Thread2内部run方法要用同一对象作为监视器，我们这里不能用this，因为在Thread2里面的this和这个Thread1的this不是同一个对象。我们用MultiThread.class这个字节码对象，当前虚拟机里引用这个变量时，指向的都是同一个对象。
???synchronized (MultiThread.class) {
????System.out.println("enter thread1...");
????
????System.out.println("thread1 is waiting");
????try {
???//释放锁有两种方式，第一种方式是程序自然离开监视器的范围，也就是离开了synchronized关键字管辖的代码范围，另一种方式就是在synchronized关键字管辖的代码内部调用监视器对象的wait方法。这里，使用wait方法释放锁。
?????MultiThread.class.wait();
????} catch (InterruptedException e) {
?????// TODO Auto-generated catch block
?????e.printStackTrace();
????}
????
????System.out.println("thread1 is going on...");
????System.out.println("thread1 is being over!");???
???}
??}
??
?}
?
?private static class Thread2 implements Runnable
?{
?
??public void run() {
???// TODO Auto-generated method stub
???synchronized (MultiThread.class) {
???
????System.out.println("enter thread2...");
????
????System.out.println("thread2 notify other thread can release wait status..");
//由于notify方法并不释放锁， 即使thread2调用下面的sleep方法休息了10毫秒，但thread1仍然不会执行，因为thread2没有释放锁，所以Thread1无法得不到锁。
????MultiThread.class.notify();
????
????System.out.println("thread2 is sleeping ten millisecond...");
????try {
?????Thread.sleep(1000);
????} catch (InterruptedException e) {
?????// TODO Auto-generated catch block
?????e.printStackTrace();
????}
????
????System.out.println("thread2 is going on...");
????System.out.println("thread2 is being over!");
????
???}
??}
??
?}?
}
注解：wait()使进同步方法的线程战时让出锁 放在锁吃池里面，让其他线程去竞争。当其他线程调用notify（）唤醒调用过wait()方法的线程，如果此时notify线程后面还有代码那么久先执行此线程后面的代码，然后执行以前调用过wait（）方法的线程
?
