OnJava8-Examples/network/MultiSimpleClient.java

// network/MultiSimpleClient.java
// (c)2016 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
// Client that tests the MultiSimpleServer
// by starting up multiple clients.
// {ValidateByHand}
import java.net.*;
import java.io.*;
import onjava.*;

class SimpleClientThread extends Thread {
  private Socket socket;
  private BufferedReader in;
  private PrintWriter out;
  private static int counter = 0;
  private int id = counter++;
  private static int threadcount = 0;
  public static int threadCount() {
    return threadcount;
  }
  public SimpleClientThread(InetAddress addr) {
    System.out.println("Making client " + id);
    threadcount++;
    try {
      socket =
        new Socket(addr, MultiSimpleServer.PORT);
    } catch(IOException e) {
      // If the creation of the socket fails,
      // nothing needs cleanup.
    }
    try {
      in =
        new BufferedReader(
          new InputStreamReader(
            socket.getInputStream()));
      // Enable auto-flush:
      out =
        new PrintWriter(
          new BufferedWriter(
            new OutputStreamWriter(
              socket.getOutputStream())), true);
      start();
    } catch(IOException e) {
      // The socket should be closed on any
      // failures other than the socket
      // constructor:
      try {
        socket.close();
      } catch(IOException e2) {}
    }
    // Otherwise the socket will be closed by
    // the run() method of the thread.
  }
  @Override
  public void run() {
    try {
      for(int i = 0; i < 25; i++) {
        out.println("Client " + id + ": " + i);
        String str = in.readLine();
        System.out.println(str);
      }
      out.println("END");
    } catch(IOException e) {
    } finally {
      // Always close it:
      try {
        socket.close();
      } catch(IOException e) {}
      threadcount--; // Ending this thread
    }
  }
}

public class MultiSimpleClient {
  static final int MAX_THREADS = 40;
  public static void main(String[] args)
      throws IOException, InterruptedException {
    new TimedAbort(5); // Terminate after 5 seconds
    InetAddress addr =
      InetAddress.getByName(null);
    while(true) {
      if(SimpleClientThread.threadCount()
         < MAX_THREADS)
        new SimpleClientThread(addr);
      Thread.sleep(100);
    }
  }
}