通过管道进行线程间通信：字节流。字符流的用法及API类似

管道流（PipedStream）可以用于不同线程间直接传送数据。
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取数据。通过使用管道，实现不同线程间的通信，而无须借助于类似临时文件之类的东西。

package thread.communicate;

import java.io.IOException;
import java.io.PipedInputStream;
import java.io.PipedOutputStream;

/*2015-11-19*/
public class CommunicateWithPipedStream {
    public static void main(String[] args) {
        try {
            PipedOutputStream out = new PipedOutputStream();
            DataWriter writer = new DataWriter(out);
            PipedInputStream in = new PipedInputStream();
            DataReader reader = new DataReader(in);
            // out.connect(in);
            in.connect(out);
         new Thread(writer, "Writer").start();
            new Thread(reader, "Reader").start();
        } catch (Exception e) {
            e.printStackTrace();
        }

    }
}

class DataWriter implements Runnable {
    private PipedOutputStream _out;

    public DataWriter(PipedOutputStream out) {
        super();
        this._out = out;
    }

    @Override
    public void run() {
        write();
    }

    public void write() {
        System.out.println(Thread.currentThread() + "Start write....");
        try {
            for (int i = 0; i < 20; i++) {
                String outStr = "" + (i + 1);
                System.out.println(Thread.currentThread() + outStr);
                _out.write(outStr.getBytes());
            }
            _out.close();

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

    }

}

class DataReader implements Runnable {

    private PipedInputStream _in;

    public DataReader(PipedInputStream in) {
        _in = in;
    }

    @Override
    public void run() {
        read();
    }

    public void read() {
        try {
            System.out.println(Thread.currentThread() + "Start read....");
            byte[] byteArray = new byte[20];
            int readLength = _in.read(byteArray);
            while (readLength != -1) {
                String newData = new String(byteArray, 0, readLength);
                System.out.println(Thread.currentThread() + newData);
                readLength = _in.read(byteArray);
            }
            System.out.println();
            _in.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

}

输出：

Thread[Writer,5,main]Start write....
Thread[Writer,5,main]1
Thread[Reader,5,main]Start read....
Thread[Writer,5,main]2
Thread[Reader,5,main]1
Thread[Reader,5,main]2
Thread[Writer,5,main]3
Thread[Writer,5,main]4
Thread[Writer,5,main]5
Thread[Writer,5,main]6
Thread[Writer,5,main]7
Thread[Writer,5,main]8
Thread[Writer,5,main]9
Thread[Writer,5,main]10
Thread[Writer,5,main]11
Thread[Writer,5,main]12
Thread[Writer,5,main]13
Thread[Writer,5,main]14
Thread[Writer,5,main]15
Thread[Writer,5,main]16
Thread[Writer,5,main]17
Thread[Writer,5,main]18
Thread[Writer,5,main]19
Thread[Writer,5,main]20
Thread[Reader,5,main]34567891011121314151
Thread[Reader,5,main]617181920