Java > Threads > Using pipes for inter-thread I/O

// : c13:PipedIO.java
// Using pipes for inter-thread I/O
// From 'Thinking in Java, 3rd ed.' (c) Bruce Eckel 2002
// www.BruceEckel.com. See copyright notice in CopyRight.txt.
import java.util.Timer;
import java.util.TimerTask;

import java.io.IOException;
import java.io.PipedReader;
import java.io.PipedWriter;
import java.util.Random;

class Sender extends Thread {
  private Random rand = new Random();

  private PipedWriter out = new PipedWriter();

  public PipedWriter getPipedWriter() {
    return out;
  }

  public void run() {
    while (true) {
      for (char c = 'A'; c <= 'z'; c++) {
        try {
          out.write(c);
          sleep(rand.nextInt(500));
        } catch (Exception e) {
          throw new RuntimeException(e);
        }
      }
    }
  }
}

class Receiver extends Thread {
  private PipedReader in;

  public Receiver(Sender sender) throws IOException {
    in = new PipedReader(sender.getPipedWriter());
  }

  public void run() {
    try {
      while (true) {
        // Blocks until characters are there:
        System.out.println("Read: " + (char) in.read());
      }
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }
}

public class PipedIO {
  public static void main(String[] args) throws Exception {
    Sender sender = new Sender();
    Receiver receiver = new Receiver(sender);
    sender.start();
    receiver.start();
    new Timeout(4000, "Terminated");
  }
} ///:~
class Timeout extends Timer {
  public Timeout(int delay, final String msg) {
    super(true); // Daemon thread
    schedule(new TimerTask() {
      public void run() {
        System.out.println(msg);
        System.exit(0);
      }
    }, delay);
  }
}