同步代码块 synchronized

public class demon_syn {

    public static void main(String[] args) {
        final printer p = new printer();
        new Thread(){
            public void run() {
                while(true){
                    p.print1();
                }
            }
        }.start();
        new Thread(){
            public void run() {
                while(true){
                    p.print2();
                }
            }
        }.start();
    }
}
class printer{
    demo d1 = new demo();
    public  void print1(){
        synchronized (d1) { 　　　　　　　　//锁对象可以是任意对象,但是被锁的代码需要保证是同一把锁,不能用匿名对象
            System.out.print("黑");
            System.out.print("马");
            System.out.print("程");
            System.out.print("序");
            System.out.print("员");
            System.out.print("\r\n");
        }
        
        
    }
    public  void print2(){
        synchronized (d1) {
            System.out.print("传");
            System.out.print("智");
            System.out.print("播");
            System.out.print("客");
            System.out.print("\r\n");
        }
        
    }
}

class demo{
    
}