testsenderandreceiver.java

多线程 课堂讲解代码 很经典的

public class TestSenderAndReceiver {
  public static void main (String args[ ]) {
    SharedBuffer buffer = new SharedBuffer () ;
    Sender s1 = new Sender (buffer) ;
    Receiver r2 = new Receiver (buffer) ;
    s1.start () ;
    r2.start () ;
  } // main方法结束
} // 类TestSenderAndReceiver结束

//声明发送者类
class Sender extends Thread {
  SharedBuffer theBuffer ;

  public Sender (SharedBuffer s) {
    theBuffer = s ;
  }

  public void run () {
    char c ;
    for (int i = 0 ;i < 5 ;i++) {
      c = (char) (Math. random()*31 +'A');
      theBuffer.send(c) ;
      System.out .println("Sender : "+ c) ;
      try{
        Thread.sleep( ( int ) ( Math.random() * 1000 ) );
      }catch ( InterruptedException e ){
        System.out.println("Exception:" + e.getMessage());
      } // try/catch 块结束
    } // for 结束
  } // run()方法结束
} // 类Sender结束

// 声明接收者类
class Receiver extends Thread {
  SharedBuffer theBuffer ;

  public Receiver (SharedBuffer s) {
    theBuffer = s ;
  }

  public void run () {
    char c ;
    for (int i = 0 ;i < 5 ;i++) {
      c = theBuffer.receive () ;
      System.out.println("Receiver : "+ c) ;
      try{
        Thread.sleep( ( int ) ( Math.random() * 3000 ) );
      }catch ( InterruptedException e ){
        System.out.println("Exception:" + e.getMessage());
      } // try/catch块结束
    } // for结束
  } // run()方法结束
} // 类Receiver结束

// 共享缓冲区类
class SharedBuffer {
  private static int BUFFERSIZE = 5;
  private int index = 0 ;
  private char buf [ ] = new char[ BUFFERSIZE ] ;

  public synchronized void send (char c) {
    while (index == buf.length) { // 如果缓冲区已满，则发送线程等待
      try {
        wait();
      } catch( InterruptedException e) {}
    } // while结束
    notify();
    buf[index] = c ;
    index++;
  } // send()方法结束

 public synchronized char receive () {
   while (index == 0) { // 如果缓冲区空，则接受线程等待
     try {
       wait () ;
     } catch( InterruptedException e) {}
   } // while结束
   notify();  //接受线程接受后唤醒发送线程发送数据
   index-- ;
   return buf[index] ;
  } // receive方法结束
} // 类SharedBuffer结束