java 多线程synchronized互斥锁demo

import java.sql.Timestamp; public class Long{ private int i = 0; private static Object lock = new Object(); // static确保只有一把锁 public void increaseI() { synchronized (lock) {//加锁 for(int k=0;k<10;k++) { // 对i执行10次增1操作 i++; } System.out.println(Thread.currentThread().getName() + "线程, i现在的值：" + i); } } public static void main(String[] args){ int threadNum = 1000; // 选择1000个线程让结果更加容易观测到 Long ld = new Long(); MyThread[] threads = new MyThread[threadNum]; for(int i=0;i<threads.length;i++) { threads[i] = new Long().new MyThread(ld); // 所有线程共用一个LockDemo对象 threads[i].start(); } } class MyThread extends Thread{ Long ld; public MyThread(Long ld) { this.ld = ld; } public void run() { ld.increaseI(); } } }