多线程使用PipedStream 通讯

Java 提供了四个相关的管道流，我们可以使用其在多线程进行数据传递,其分别是

类名	作用	备注
PipedInputStream	字节管道输入流	字节流
PipedOutputStream	字节管道输出流	字节流
PipedReader	字符管道读取	字符流
PipedWriter	字符管道写入	字符流

其分为两类：字节流和字符流，基本步骤为：线程A写入数据到输出流/写入，线程B读取数据从输入流/字符读取,从而实现线程通讯，下面我们先看下基于字节流的实现方法.

写数据到输出流

package com.zhoutao.demo.thread.piped;import java.io.IOException;import java.io.PipedOutputStream;import java.util.concurrent.TimeUnit;public class WriteData {  private int count = 0;  public void writeMethod(PipedOutputStream pipedOutputStream) throws InterruptedException, IOException {    while (true) {        // 每隔1s向输出流写入数字字符串      pipedOutputStream.write(String.valueOf(count++).getBytes());      TimeUnit.SECONDS.sleep(1);    }  }}

读数据从输入流

package com.zhoutao.demo.thread.piped;import java.io.IOException;import java.io.PipedInputStream;public class ReadData {  public void readMethod(PipedInputStream inputStream) throws IOException {    byte[] bytes = new byte[20];    int read;      // 当流中不存在数据时候，read方法会进入阻塞状态    while ((read = inputStream.read(bytes)) != -1) {      String newData = new String(bytes, 0, read);      System.out.println("Get Data = " + newData);    }  }}

启动测试

package com.zhoutao.demo.thread.piped;import java.io.IOException;import java.io.PipedInputStream;import java.io.PipedOutputStream;public class PipesStreamDemo {  public static void main(String[] args) throws IOException {    // 创建读写对象    WriteData writeData = new WriteData();    ReadData readData = new ReadData();    // 创建管道输入输出流    PipedInputStream pipedInputStream = new PipedInputStream();    PipedOutputStream pipedOutputStream = new PipedOutputStream();    // 重点:连接管道流    pipedOutputStream.connect(pipedInputStream);    // 创建对应的线程并启动    ThreadRead threadRead = new ThreadRead(readData, pipedInputStream);    ThreadWrite threadWrite = new ThreadWrite(writeData, pipedOutputStream);    threadRead.start();    threadWrite.start();        // 观察控制台输出的数据  }  static class ThreadRead extends Thread {    private ReadData readData;    private PipedInputStream inputStream;    public ThreadRead(ReadData readData, PipedInputStream inputStream) {      this.readData = readData;      this.inputStream = inputStream;    }    @Override    public void run() {      try {        readData.readMethod(inputStream);      } catch (IOException e) {        e.printStackTrace();      }    }  }  static class ThreadWrite extends Thread {    private WriteData writeData;    private PipedOutputStream pipedOutputStream;    public ThreadWrite(WriteData writeData, PipedOutputStream pipedOutputStream) {      this.writeData = writeData;      this.pipedOutputStream = pipedOutputStream;    }    @Override    public void run() {      try {        writeData.writeMethod(pipedOutputStream);      } catch (InterruptedException e) {        e.printStackTrace();      } catch (IOException e) {        e.printStackTrace();      }    }  }}

测试数据

Get Data = 0Get Data = 1Get Data = 2Get Data = 3Get Data = 4Get Data = 5Get Data = 6Get Data = 7