目录

Java通过管道进行进程间通信

目录

Java通过管道进行进程间通信

Java语言中提供了各种各样的输入输出流Stream,使我们能够很方便地对数据进行操作,其中管道流(pipeStream)是一种特殊的流,用于在不同线程间之间传送数据。一个线程发送数据到输出管道,另一个线程从输入管道中读数据。通过使用管道,实现不同线程间的通信,而无须借助类似于临时文件之类的东西。

在Java的JDK中提供了4个类来使线程间可以相互通信:

1)PipedInputSteam和PipedOutputStream

2)PipedReader和PipedWriter

PipedReader和PipedWriter在管道间传送字符流,下面以其为例说明使用。

ThreadWrite类,发送数据的线程。

import java.io.IOException;
import java.io.PipedWriter;

public class ThreadWrite extends Thread{
    private PipedWriter out;

    public ThreadWrite(PipedWriter out){
        super();
        this.out = out;
    }
    @Override
    public void run(){
        try{
            System.out.println("write:");
            for(int i=0;i<300;i++){
                String outData = ""+(i+1);
                out.write(outData);
                System.out.print(outData);
            }
            System.out.println();
            out.close();
        }catch (IOException e){
            e.printStackTrace();
        }
    }
}

ThreadRead类,读取数据的线程。

import java.io.IOException;
import java.io.PipedReader;

public class ThreadRead extends Thread{
    private PipedReader input;

    public ThreadRead(PipedReader input){
        super();
        this.input = input;
    }

    @Override
    public void run(){

        try{
            System.out.println("read:");
            char[] byteArray = new char[100];
            int readLength = input.read(byteArray);
            while (readLength!=-1){
                String newData = new String(byteArray,0,readLength);
                System.out.print(newData);
                readLength = input.read(byteArray);
            }
            System.out.println();
            input.close();

        }catch (IOException e){
            e.printStackTrace();
        }
    }
}

测试类:

import java.io.PipedReader;
import java.io.PipedWriter;

public class RunTest {

    public static void main(String[] args){
        try{

            PipedReader pipedReader = new PipedReader();
            PipedWriter pipedWriter = new PipedWriter();

            //inputStream.connect(outputStream);
            pipedWriter.connect(pipedReader);   //将pipedWriter和pipeRead通过connect相连

            ThreadRead threadRead = new ThreadRead(pipedReader);    //启动读线程
            threadRead.start();

            Thread.sleep(2000);

            ThreadWrite threadWrite = new ThreadWrite(pipedWriter);  //启动写线程
            threadWrite.start();

        }catch (IOException e){
            e.printStackTrace();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

}

程序输入如下所示:

https://img-blog.csdn.net/20160501122811391

参考《Java多线程编程核心技术》