SocketPool.java

/**
 * Sahi - Web Automation and Test Tool
 *
 * Copyright  2006  V Narayan Raman
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package net.sf.sahi.util;

import org.apache.log4j.Logger;

import java.io.IOException;
import java.net.BindException;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.SocketException;
import java.util.LinkedList;
import java.util.List;

/**
 * Unused
 *
 * @author Narayan Raman
 */
public class SocketPool {

  private final List<Integer> unused = new LinkedList<Integer>();

  private static int START_PORT = 13300;

  private int lastPort;
  private static Logger logger = Logger.getLogger(SocketPool.class);

  public SocketPool(final int size) {
    for (int i = 0; i < size; i++) {
      returnToPool(START_PORT + i);
    }
    lastPort = START_PORT + size;
  }

  private Socket createSocket(final int port) throws IOException {
    Socket socket = new Socket();
    try {
      socket.setSoLinger(true, 0);
      socket.setReuseAddress(true);
      socket.bind(new InetSocketAddress(port));
    } catch (SocketException e) {
      e.printStackTrace();
    }
    return socket;
  }

  Socket get() throws IOException {
    Socket socket;
    int port;
    synchronized (unused) {
      while (unused.isEmpty()) {
        try {
          logger.debug("Waiting for socket");
          unused.wait();
        } catch (InterruptedException e) {
          System.out.println("Interrupted!");
        }
      }
      port = ((Integer) unused.remove(0)).intValue();
      socket = createSocket(port);
    }
    logger.debug("Get: " + port);
    return socket;
  }

  public Socket get(final String host, final int port) throws IOException {
    Socket socket = get();
    try {
      logger.debug("Trying: " + socket.getLocalPort());
      socket.connect(new InetSocketAddress(host, port));
    } catch (BindException e) {
      e.printStackTrace();
      lastPort++;
      System.out.println("### Creating New Socket : " + lastPort);
      socket = createSocket(lastPort);
      socket.connect(new InetSocketAddress(host, port));
    } catch (IOException e) {
      System.out.println("Error while connecting to " + host + ":" + port);
      release(socket);
      throw e;
    }
    return socket;
  }

  public void release(final Socket socket) {
    try {
      socket.close();
    } catch (IOException e) {
      e.printStackTrace();
    }
    logger.debug("#socket.getLocalPort()="+socket.getLocalPort());
    logger.debug("#socket.isClosed()="+socket.isClosed());
    logger.debug("#socket.isBound()="+socket.isBound());
    logger.debug("#socket.isInputShutdown()="+socket.isInputShutdown());
    logger.debug("#socket.isOutputShutdown()="+socket.isOutputShutdown());
    logger.debug("#socket.isConnected()="+socket.isConnected());
    returnToPool(socket.getLocalPort());
  }

  void returnToPool(final int port) {
    logger.debug("returned to Pool " + port);
    synchronized (unused) {
      unused.add(new Integer(port));
      unused.notifyAll();
    }
  }
}