一个线程同步例子

package javase2.day05;

import javase2.day05.Table.Person;

/**

* 临界资源访问

**/

public class SyncDemo1 {

public static void main(String[] args) {

Table table = new Table();

Person p1 = table.new Person();

Person p2 = table.new Person();

p1.start();

p2.start();

}

}

class Table{

int beans=20;

Object monitor = new Object(); //同步监视器, 同步锁//boolean monitor.lock = false

public synchronized int getBean(){

int a = 5;

if(beans==0)

throw new RuntimeException("没了");

Thread.yield();

return beans--;

}

// public int getBean(){

// synchronized(this){

// int a = 5;

// if(beans==0)

// throw new RuntimeException("没了");

// Thread.yield();

// return beans--;

// }

// }

// public int getBean(){

// synchronized(monitor){

// int a = 5;

// if(beans==0)

// throw new RuntimeException("没了");

// Thread.yield();

// return beans--;

// }

// }

// public int getBean(){

// if(beans==0)

// throw new RuntimeException("没了");

// //Thread.yield();

// try{

// Thread.sleep(1);

// }catch(InterruptedException e){

// e.printStackTrace();

// }

// return beans--;

// }

class Person extends Thread{

public void run(){

while(true){

int bean = getBean();

System.out.println(getName()+"拿到:"+bean);

Thread.yield();

}

}

}

}