import java.util.concurrent.Exchanger;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

class Cup {
    
    int waterVolume = 0;
    
    String cupName="";
    public String getCupName() {
        return cupName;
    }
    
    public void setCupName(String cupName) {
        this.cupName = cupName;
    }
    Cup(int i ,String name){
        waterVolume=i;
        cupName=name;
    }
    @Override
    public String toString() {
        // TODO Auto-generated method stub
        return cupName+"有"+waterVolume+"升水！";
    }
    public int getWaterVolume() {
        return waterVolume;
    }
    public void drinkWater(){
        waterVolume--;
    }
    public void drinkWater( int i ){
        if((waterVolume-i)>=0){
           waterVolume-=i;
        }else{
            System.out.println("没有这么多水可以喝！！！");
            return;
        }
    }
    public void addWater(){
        waterVolume++;
    }
    public void addWater(int i){
        waterVolume=i;
    }
}

class Drinker implements Runnable{
    Cup currentCup;
    Exchanger ex;
    Drinker(Exchanger ex,Cup c){
        currentCup= c;
        this.ex= ex;
    }
    @Override
    public void run() {
        //得到杯子喝水
        /*try {
            currentCup = (Cup)ex.exchange(currentCup);
        } catch (InterruptedException e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }*/
        boolean flag = true;
        while(flag){
            if(currentCup.getWaterVolume() > 0){
                System.out.println("喝水者："+currentCup);
                System.out.println("喝水者：从"+currentCup.getCupName()+"喝2升水，喝水用时1秒");
                currentCup.drinkWater(2);
                try {
                    TimeUnit.SECONDS.sleep(1);
                } catch (InterruptedException e) {
                    // TODO: handle exception
                    e.printStackTrace();
                }
            }
            if(currentCup.getWaterVolume() == 0){
                System.out.println("喝水者："+currentCup+",水喝光了！别加了！");
                flag=false;
            }
            //服务员加完水后的杯子
            try {
                currentCup = (Cup)ex.exchange(currentCup);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        
    }
    
}

class Waiter implements Runnable{
    Cup currentCup;
    Exchanger ex;
    Waiter(Exchanger ex,Cup c){
        currentCup= c;
        this.ex= ex;
    }
    @Override
    public void run() {
        //得到杯子加水
        /*try {
            currentCup = (Cup)ex.exchange(currentCup);
        } catch (InterruptedException e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }*/
        boolean flag = true;
        while(flag){
            System.out.println("服务员："+currentCup);
            System.out.println("服务员：倒入"+currentCup.getCupName()+"  1升水，耗时1秒");
            try {
                TimeUnit.SECONDS.sleep(1);
            } catch (InterruptedException e) {
                // TODO: handle exception
                e.printStackTrace();
            }
            currentCup.addWater();
            //得到顾客递过来的杯子
            try {
                currentCup=(Cup)ex.exchange(currentCup);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            if(currentCup.getWaterVolume() == 0){
                System.out.println("服务员："+currentCup+"水喝光了！！不加了！");
                flag=false;
            }
        }
        
    }
}


public class DrinkWaterDemo {
    public static void main(String[] args) {
        Cup cup1 = new Cup(3,"cup1");
        Cup cup2 = new Cup(0,"cup2");
        final Exchanger<Cup> ec = new Exchanger<Cup>();
        ExecutorService es = Executors.newFixedThreadPool(2);
        es.submit(new Waiter(ec,cup2));
        es.submit(new Drinker(ec, cup1));
        es.shutdown();
        
    }
}