import java.awt.*;
import java.awt.event.*;
public class Card extends WindowAdapter 
{
    Frame f;
    TextArea ta1,ta2,ta3,ta4;
    public void display()
    {
        f = new Frame("Send Card");
        f.setSize(400,300);
        f.setLocation(200,140);
        f.setBackground(Color.lightGray);
        f.setLayout(new GridLayout(2,2));
        f.addWindowListener(this);
        ta1 = new TextArea("",5,10,3);           //文本區沒有滾動條
        ta2 = new TextArea("",5,10,3);
        ta3 = new TextArea("",5,10,3);
        ta4 = new TextArea("",5,10,3);
        Font font1 = new Font("Helvetica", Font.PLAIN, 20);
        ta1.setFont(font1);
        ta2.setFont(font1);
        ta3.setFont(font1);
        ta4.setFont(font1);
        f.add(ta1);
        f.add(ta2);
        f.add(ta4);
        f.add(ta3);
        f.setVisible(true);
    }
    public void windowClosing(WindowEvent e)
    {
        System.exit(0);
    }
    public static void main(String arg[])
    {
        Card p = new Card();
        p.display();
        Buffer3 bf = new Buffer3();
        Sender3 s = new Sender3(bf,52);
        s.start();                               //啟動發牌線程
        s.setPriority(1);                        //設置最高優先級,值為1
        Receiver3 r1=new Receiver3(bf,p.ta1);    //創建四個取牌線程
        Receiver3 r2=new Receiver3(bf,p.ta2);
        Receiver3 r3=new Receiver3(bf,p.ta3);
        Receiver3 r4=new Receiver3(bf,p.ta4);
        r1.start();                        //啟動取牌線程,優先級為5
        r2.start();
        r3.start();
        r4.start();
    }
}
class Buffer3                              //加互斥鎖的緩沖區
{
    private int value;
    private boolean isEmpty = true;        //value是否為空的信號量
    private int sort=0;               //設定當前取牌線程的順序值,從0－3
    synchronized void put(int i)
    {
        while (!isEmpty)                   //當value不空時,等待
        {
            try
            {
                 wait();                   //等待
            }
            catch(InterruptedException e)
            {
                 System.out.println(e.getMessage());
            }
        }
        value = i;                         //當value空時,value獲得值
        isEmpty = false;                   //設置value為不空狀態
        notifyAll();                       //喚醒所有其他等待線程
    }
    synchronized int get(String name)      //name是當前準備取牌的ta組件名
    {
        int ptr;
        //System.out.println(name);        //組件名為：text0－text3
        ptr=Integer.parseInt(name.substring(4));//獲取組件ta的編號0－3
        while (isEmpty||(ptr!=sort))
        {                      //當value空或組件編號與順序值不符時,等待
            try
            {
                 wait();
            }
            catch(InterruptedException e)
            {
                 System.out.println(e.getMessage());
            }
        }
        isEmpty = true;                    //設置value為空狀態,并返回值
        notifyAll();
        sort=(sort+1)%4;                   //順序值加1
        return value;                      
    }
}
class Sender3 extends Thread               //發牌線程
{
    private Buffer3 bf;
    int count;
    public Sender3(Buffer3 bf,int c)
    {
        this.bf = bf;
        this.count = c;
    }
    public void run( )
    {
        for (int i=1;i<=count;i++)
            bf.put( i );
    }
}
class Receiver3 extends Thread             //取牌線程
{
    private Buffer3 bf;
    TextArea ta;
    public Receiver3(Buffer3 bf,TextArea ta)
    {
        this.bf = bf ;
        this.ta = ta ;
    }
    synchronized public void run()
    {
        while(true)
        {
            ta.append(" " +bf.get(ta.getName()));
            try
            {
                 wait(1000);
            }
            catch(InterruptedException e)
            {
                 System.out.println(e.getMessage());
            }
        }
    }
}