Java创建多线程的两种方式对比

 package org.frzh.thread;
 
 public class FirstThread extends Thread{
     private int i;
    
     //重写run方法，run方法的方法体就是线程执行体
     public void run() {
         for (; i < 100; i++) {
             //当线程类继承Thread类时，可以直接调用getName方法获得当前线程名
             //如果想获得当前线程，直接使用this
             //Thread对象的getName方法返回当前线程的名字
             System.out.println(getName() + " " + i);
         }
     }
    
     public static void main(String[] args) {
         for (int i = 0; i < 100; i++) {
             //调用Thead的currentThread方法获取当前线程
             System.out.println(Thread.currentThread().getName() + " " +i);
             if (i == 20) {
                 new FirstThread().start();
                 new FirstThread().start();
             }
         }
     }
 }

 package org.frzh.thread;
 
 public class SecondThread implements Runnable{
     private int i;
    
     @Override
     public void run() {
         // TODO Auto-generated method stub
         for (; i < 100; i++) {
             System.out.println(Thread.currentThread().getName() + " " + i);
         }
     }
    
     public static void main(String[] args) {
         for (int i = 0; i < 100; i++) {
             System.out.println(Thread.currentThread().getName() + " " + i);
             if (i == 20) {
                 SecondThread st = new SecondThread();
                 new Thread(st, "子线程1").start();
                 new Thread(st, "子线程2").start();
             }
         }
     }
 
 }