實例分析：例2：使用管道流完成線程之間的通訊。 – JAVA編程語言程序開發技術文章

1 問題分析

本題中需要一個線程向管道寫入數據，另外一個線程從管道中讀出數據，需要使用到與管道有關的流PipedInputStream和PipedOutputStream。

2 使用管道流

PipedInputStream和PipedOutputStream

管道流用來在線程間進行通信。一個線程的PipedInputStream對象從另一個線程的PipedOutputStream對象讀取輸入。要使管道流有用，必須有一個輸入方和一個輸出方。

PipedInputStream  in=new PipedInputStream();

PipedOutputStream out=new PipedOutputStream(in);

3 編寫代碼

[java]
import java.io.*; 
 
public class TestPipeStream { 
    public static void main(String[] args) { 
        try { 
            PipedInputStream in1 = new PipedInputStream(); 
            PipedOutputStream out1 = new PipedOutputStream(in1); 
 
            PipedInputStream in2 = new PipedInputStream(); 
            PipedOutputStream out2 = new PipedOutputStream(in2); 
 
            ThreadC tc = new ThreadC(out1); 
            ThreadZ tz = new ThreadZ(out2, in1); 
            ThreadQ tq = new ThreadQ(in2); 
            tc.start(); 
            tz.start(); 
            tq.start(); 
        } catch (Exception e) { 
            e.printStackTrace(); 
        } 
    } 
 
    static class ThreadC extends Thread { 
        DataOutputStream dos = null; 
 
        public ThreadC(OutputStream os) { 
            dos = new DataOutputStream(os); 
        } 
 
        public void run() { 
            while (true) { 
                try { 
                    double d = Math.random(); 
                    dos.writeDouble(d); 
                    sleep(2); 
                } catch (Exception e) { 
                    e.printStackTrace(); 
                } 
            } 
        } 
    }; 
 
    static class ThreadZ extends Thread { 
        DataOutputStream dos = null; 
 
        DataInputStream dis = null; 
 
        public ThreadZ(OutputStream os, InputStream is) { 
            dos = new DataOutputStream(os); 
            dis = new DataInputStream(is); 
        } 
 
        public void run() { 
            while (true) { 
                try { 
                    double d = dis.readDouble(); 
                    dos.writeDouble(d); 
                } catch (Exception e) { 
                    e.printStackTrace(); 
                } 
            } 
        } 
    }; 
 
    static class ThreadQ extends Thread { 
        DataInputStream dis = null; 
 
        public ThreadQ(InputStream is) { 
            dis = new DataInputStream(is); 
        } 
 
        public void run() { 
            while (true) { 
                try { 
                    double d = dis.readDouble(); 
                    System.out.println(d); 
                } catch (Exception e) { 
                    e.printStackTrace(); 
                } 
            } 
        } 
    }; 
} 
import java.io.*;

public class TestPipeStream {
 public static void main(String[] args) {
  try {
   PipedInputStream in1 = new PipedInputStream();
   PipedOutputStream out1 = new PipedOutputStream(in1);

   PipedInputStream in2 = new PipedInputStream();
   PipedOutputStream out2 = new PipedOutputStream(in2);

   ThreadC tc = new ThreadC(out1);
   ThreadZ tz = new ThreadZ(out2, in1);
   ThreadQ tq = new ThreadQ(in2);
   tc.start();
   tz.start();
   tq.start();
  } catch (Exception e) {
   e.printStackTrace();
  }
 }

 static class ThreadC extends Thread {
  DataOutputStream dos = null;

  public ThreadC(OutputStream os) {
   dos = new DataOutputStream(os);
  }

  public void run() {
   while (true) {
    try {
     double d = Math.random();
     dos.writeDouble(d);
     sleep(2);
    } catch (Exception e) {
     e.printStackTrace();
    }
   }
  }
 };

 static class ThreadZ extends Thread {
  DataOutputStream dos = null;

  DataInputStream dis = null;

  public ThreadZ(OutputStream os, InputStream is) {
   dos = new DataOutputStream(os);
   dis = new DataInputStream(is);
  }

  public void run() {
   while (true) {
    try {
     double d = dis.readDouble();
     dos.writeDouble(d);
    } catch (Exception e) {
     e.printStackTrace();
    }
   }
  }
 };

 static class ThreadQ extends Thread {
  DataInputStream dis = null;

  public ThreadQ(InputStream is) {
   dis = new DataInputStream(is);
  }

  public void run() {
   while (true) {
    try {
     double d = dis.readDouble();
     System.out.println(d);
    } catch (Exception e) {
     e.printStackTrace();
    }
   }
  }
 };
}

編譯運行

javac TestPipeStream.java

java TestPipeStream

 

摘自  Java教程