[Java] 纯文本查看 复制代码

class Window extends Thread{
	static int num = 1;
	public Window(String name){
		super(name);
	}
	@Override
	public void run() {
		for(;num <= 50; num++){
			try{
				synchronized ("锁"){
				this.sleep(100);
				System.out.println(Thread.currentThread().getName() + "售出" + num + "号");
				}
			}catch(InterruptedException e){};
		}
		
	}
}

public class ticket {
	public static void main(String[] args) {
		Window w1 = new Window("窗口1");	
		Window w2 = new Window("窗口2");	
		Window w3 = new Window("窗口3");
		w1.start();
		w2.start();
		w3.start();
	}
}

为什么会出现51，52张票，是因为for的原因吗？while就没有

[Java] 纯文本查看 复制代码

class Window extends Thread{
	static int num = 1;
	public Window(String name){
		super(name);
	}
	@Override
	public void run() {
		for(;num <= 50; num++){
			try{
				synchronized ("锁"){
				this.sleep(100);
				System.out.println(Thread.currentThread().getName() + "售出" + num + "号");
				}
			}catch(InterruptedException e){};
		}
		
	}
}

public class ticket {
	public static void main(String[] args) {
		Window w1 = new Window("窗口1");	
		Window w2 = new Window("窗口2");	
		Window w3 = new Window("窗口3");
		w1.start();
		w2.start();
		w3.start();
	}
}

为什么会出现51，52张票，是因为for的原因吗？while就没有