/**
* 生產者消費者問題.(蜜蜂Bee,熊Bear)
* 蜜蜂產蜜到罐子中,產滿進入等待并通知熊大熊二來吃漓帅。
* 熊從罐子里吃蜂蜜,罐子不足10L時等待.攢滿10L時吃.
* 罐子在某一時刻只能被熊或蜜蜂獨占(synchronized同步).
* 由于可能產生死鎖,解決方案(1.等待一段時間后重新?lián)屨?2.notifyAll 多人強占)
*/

class Bee extends Thread{
    private String name ;  //蜜蜂的名字,代號
    private java.util.List<Integer> jar ;  //蜜罐
    final static int MAX = 10 ; //蜜罐的最大容量L
    //構造函數(shù)
    public Bee(String name,java.util.List<Integer> jar){
        this.name = name ;
        this.jar = jar ;
    }
    //線程方法
    public void run(){
        while(true){
            synchronized(jar){      //對蜜罐進行獨占同步
                int size = jar.size();
                if(size==MAX){          //如果蜜罐滿了,就停止產蜜
                    try{
                        jar.notify();
                        jar.wait();
                    }
                    catch(Exception e){
                    }
                }
                else{                   //蜜罐沒滿就產蜜并與熊搶占蜜罐
                    jar.add(new Integer(size+1));
                    System.out.println(name+"產蜜 +1 總:"+jar.size()+"L");
                }               
            }
            yield();                    //謙讓一下
        }
    }
}


class Bear extends Thread{
    private String name ;       //熊的名字,代號
    private java.util.List<Integer> jar ;  //蜜罐
    public Bear(String name, java.util.List<Integer> jar){
        this.name = name ;
        this.jar = jar ;
    }
    //線程代碼
    public void run(){
        while(true){
            synchronized(jar){           //對蜜罐進行獨占同步
                int size = jar.size();
                if(size < 10){          //如果蜜罐空了就等待
                    try{
                        jar.wait();
                    }
                    catch(Exception e){

                    }
                }
                else{   
                    for(int i = 9 ;i >=0 ; i--){
                        jar.remove(i);
                    }
                    System.out.println(name+"吃蜜 : "+jar.size());
                    jar.notifyAll();  //notifyAll
                    try{
                        jar.wait();
                    }
                    catch(Exception e){

                    }
                }
            }
            yield();   //謙讓
        }
    }
}


class BearEatHoney{
    public static void main(String[] args) {
        java.util.List<Integer> jar = new java.util.ArrayList<Integer>();
        Bear bear1 = new Bear("Bear1",jar);
        Bear bear2 = new Bear ("Bear2",jar);
        Bee bee1 = new Bee("Bee1",jar);
        Bee bee2 = new Bee("Bee2",jar);
        Bee bee3 = new Bee("Bee3",jar);
        Bee bee4 = new Bee("Bee4",jar);
        Bee bee5 = new Bee("Bee5",jar);
        Bee bee6 = new Bee("Bee6",jar);
        Bee bee7 = new Bee("Bee7",jar);
        Bee bee8 = new Bee("Bee8",jar);
        Bee bee9 = new Bee("Bee9",jar);
        Bee bee10 = new Bee("Bee10",jar);
        
        bear1.start();
        bear2.start();
        bee1.start();
        bee2.start();
        bee3.start();
        bee4.start();
        bee5.start();
        bee6.start();
        bee7.start();
        bee8.start();
        bee9.start();
        bee10.start();
    }
}

結果:

Bee9產蜜 +1 總:1L
Bee4產蜜 +1 總:2L
Bee9產蜜 +1 總:3L
Bee4產蜜 +1 總:4L
Bee8產蜜 +1 總:5L
Bee4產蜜 +1 總:6L
Bee8產蜜 +1 總:7L
Bee2產蜜 +1 總:8L
Bee4產蜜 +1 總:9L
Bee3產蜜 +1 總:10L
Bear1吃蜜 : 0
Bee3產蜜 +1 總:1L
Bee6產蜜 +1 總:2L
Bee3產蜜 +1 總:3L
Bee1產蜜 +1 總:4L
Bee6產蜜 +1 總:5L
Bee7產蜜 +1 總:6L
Bee1產蜜 +1 總:7L
Bee10產蜜 +1 總:8L
Bee7產蜜 +1 總:9L
Bee10產蜜 +1 總:10L
Bear2吃蜜 : 0
Bee8產蜜 +1 總:1L
Bee7產蜜 +1 總:2L
Bee8產蜜 +1 總:3L
Bee1產蜜 +1 總:4L
Bee7產蜜 +1 總:5L
Bee6產蜜 +1 總:6L
Bee8產蜜 +1 總:7L
Bee1產蜜 +1 總:8L
Bee7產蜜 +1 總:9L
Bee3產蜜 +1 總:10L
Bear2吃蜜 : 0