大佬们求解释一段 Java 代码

public class MyRun implements Runnable {

	private boolean stop;

	MyRun(boolean status) {
		this.stop = status;
	}
	@Override
	public void run() {
		while(!stop) {
			// System.out.println("running");
		}
		System.out.println("stop");
	}
	public boolean isStop() {
		return stop;
	}
	public void setStop(boolean stop) {
		this.stop = stop;
	}
}


// 测试代码
MyRun myRun = new MyRun(false);
new Thread(myRun).start();
Thread.sleep(1000);// 等待线程执行
myRun.setStop(true);

上面这段代码 while 语句内容里注释掉和不注释会不会打印 stop.为什么？