简略的java多线程联络

[代码] 多线程操练 package cn.thread;

public class Through_out_bridge {

    public static void main(String[] args) {
 Bridge b = Bridge.getInstance();//实例化桥
 //实例化左端9自己，此刻所有人都不能过桥，桥的能够状况象征为不能够用
 for  ; (int i = 1; i <= 9; i  ) {
     Thread t = new Thread(new Person(false, i, b));
     t.start();
 }
 //实例化右端12自己，此刻所有人都不能过桥，桥的能够状况象征为不能够用
 for( int i=1 ;i<=12;i  )
 {
     Thread t = new Thread(new Person(true,i,b));
     t.start();
 }
 //桥的可用状况给左端第10自己，能够自定义给谁
 b.state = true;
 Thread t = new Thread(new Person(false, 10, b));
    }

}

class Person implements Runnable {

    public Bridge bridge;//桥
    private String hand;//在桥哪一端
    int No;//序号

    public Person(boolean side, int i, Bridge bridge) {

 this.No = i;
 this.bridge = bridge;
 if(bridge.state)
 {
     System.out.println(i "现已过桥。");
 }
 if (side) {
     this.hand = new String("右");
 } else {
     this.hand = new String("左");
 }
    }

    //过桥办法
    public synchronized void through() throws InterruptedException {

 if (bridge.state) {
     System.out.println(hand "边第" No   "在过桥");
     bridge.open( No);
 } else {
     bridge.lock(No);
    
}
    }

    public void run() {
 try {
     Thread.sleep(1000);
//     System.out.println(No hand " 边现已过桥!");
     through();
 } catch (InterruptedException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
 }
    }
}

class Bridge {
    //可用状况判别true：可用
    public boolean state = false;
    //自行实例化
    public static Bridge getInstance() {
 return new Bridge();
    }

    public synchronized void open(int i) throws InterruptedException {
 if (state) {
     Thread.sleep(1000);
     this.state=true;
     notify();
 }
    }

    public synchronized void lock(int i) throws InterruptedException {
 if (!state) {
     this.state=false;
     System.out.println(i   " 在等候.");
     wait();
 }
    }
} ;