Java 实现读者与写者

  1 package r_d;
  2 /**
  3  * 以下读者与写者实验以swing为主要实现
  4  */
  5 import java.awt.*;
  6 import javax.swing.*;
  7 import javax.swing.border.TitledBorder;
  8 
  9 import java.awt.event.*;
 10 import java.util.Random;
 11 import java.util.concurrent.Semaphore;
 12 import java.util.concurrent.Executors;
 13 import java.util.concurrent.ExecutorService;
 14 public class Rw2 extends JFrame implements ActionListener{
 15     /**
 16      * 
 17      */
 18     private static final long serialVersionUID = 1L;
 19     
 20     final Semaphore mutex=new Semaphore(1);
 21     final Semaphore Rmutex=new Semaphore(5);
 22     private boolean r=false;
 23     private int counter=0;
 24     ExecutorService exc=Executors.newCachedThreadPool();
 25     private Random ran=new Random();
 26     //界面设计控件
 27     Container con=getContentPane();
 28         JLabel bName,blank;
 29         JLabel []read=new JLabel[5];
 30         JLabel []w=new JLabel[2];
 31         JTextArea tf_bContent;
 32         JTextArea []tf_r=new JTextArea[5];
 33         JTextArea []tf_w=new JTextArea[2];
 34         Button b_r,b_w;
 35 
 36     public Rw2(){
 37         con.setLayout(null);
 38         setTitle("读者和写者问题");
 39         bName=new JLabel("三国演义");
 40         bName.setBounds(30, 30, 60, 40);
 41         tf_bContent=new JTextArea("《三国演义》中国古典四大名著之一");
 42         tf_bContent.setBounds(30, 60, 300, 80);
 43         tf_bContent.setBorder(new TitledBorder(null,"",TitledBorder.DEFAULT_JUSTIFICATION,
 44                 TitledBorder.DEFAULT_POSITION,null,Color.blue));
 45         blank=new JLabel();
 46         //读者控件初始化
 47         for(int i=0;i<5;i++)
 48         {
 49             
 50             read[i]=new JLabel();
 51             read[i].setText("读者"+String.valueOf(i));
 52             read[i].setBounds(10, 150+60*i, 60, 50);
 53             
 54             tf_r[i]=new JTextArea();
 55             tf_r[i].setBounds(60, 150+60*i, 100, 50);
 56             tf_r[i].setBorder(new TitledBorder(null, "", TitledBorder.DEFAULT_JUSTIFICATION, 
 57                     TitledBorder.DEFAULT_POSITION, null, Color.BLUE));
 58         
 59         }
 60         for(int j=0;j<2;j++)
 61         {
 62             w[j]=new JLabel();
 63             w[j].setText("写者"+String.valueOf(j));
 64             w[j].setBounds(200, 150+60*j, 100, 50);
 65             tf_w[j]=new JTextArea();
 66             tf_w[j].setBounds(260, 150+60*j, 100, 50);
 67             tf_w[j].setBorder(new TitledBorder(null, "", TitledBorder.DEFAULT_JUSTIFICATION, 
 68                     TitledBorder.DEFAULT_POSITION, null, Color.BLUE));
 69         }
 70         
 71         b_r=new Button("启动读者线程");
 72         b_w=new Button("启动写者线程");
 73         b_r.setBounds(400,100, 100, 50);
 74         b_w.setBounds(510,100, 100, 50);
 75         //安装行动监视器
 76         b_r.addActionListener(this);
 77         b_w.addActionListener(this);
 78         
 79       
 80         con.add(bName);
 81         con.add(tf_bContent);
 82         for(int i=0;i<5;i++)
 83         {
 84             con.add(tf_r[i]);
 85             con.add(read[i]);
 86         }
 87         for(int j=0;j<2;j++)
 88         {
 89             
 90             con.add(w[j]);
 91             con.add(tf_w[j]);
 92         }
 93         con.add(b_r);
 94         con.add(b_w);
 95         setSize(800,500);
 96         setVisible(true);
 97         //关闭窗口
 98         addWindowListener(new WindowAdapter(){
 99         public void windowClosing(WindowEvent e){
100             System.exit(0);
101         }    
102         });
103                 
104     }
105     
106     
107     Runnable run=new Runnable(){
108         public void run(){
109             if(r)
110             {
111                 try {
112                     Rmutex.acquire();
113                     if(counter==0)
114                     {
115                         try {
116                             mutex.acquire();                       
117                         } catch (InterruptedException e) {
118                             // TODO Auto-generated catch block
119                             e.printStackTrace();
120                         }
121                     }
122                     tf_r[counter].setText(tf_bContent.getText().toString()); 
123                     counter++;
124                     Thread.sleep((long)(Math.random()*10000));
125                     tf_r[counter-1].setText("");
126                     if(counter==1)
127                            mutex.release();
128                     counter--;
129                     Rmutex.release();
130                 
131                 } catch (InterruptedException e) {
132                     // TODO Auto-generated catch block
133                     //e.printStackTrace();
134                 }
135                 
136                 
137     
138             }else if(!r)
139             {
140                 try {
141                     mutex.acquire();
142                     tf_bContent.setText(tf_w[ran.nextInt(1)].getText().toString());
143                     Thread.sleep((long)(Math.random()*10000));
144                     mutex.release();
145                 } catch (InterruptedException e) {
146                     // TODO Auto-generated catch block
147                     e.printStackTrace();
148                 }
149                 
150             }
151         }
152         
153     };//run
154     @Override
155     public void actionPerformed(ActionEvent a) {
156         // TODO Auto-generated method stub
157         if(a.getSource()==b_r)
158         {
159             r=true;
160             exc.execute(run);
161             
162         }
163         else if(a.getSource()==b_w){
164             r=false;
165             exc.execute(run);
166         }
167         
168     }
169     public static void main(String args[])
170     {
171         new Rw2();
172     }
173 }