tcpmasterconnection.java

jamod is an object oriented implementation of the Modbus protocol, realized 100 in Java. It allows

//License
/***
 * Java Modbus Library (jamod)
 * Copyright (c) 2002-2004, jamod development team
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the author nor the names of its contributors
 * may be used to endorse or promote products derived from this software
 * without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS ``AS
 * IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 ***/
package net.wimpi.modbus.net;

import java.io.IOException;
import java.net.InetAddress;
import java.net.Socket;

import net.wimpi.modbus.Modbus;
import net.wimpi.modbus.io.ModbusTCPTransport;
import net.wimpi.modbus.io.ModbusTransport;

/**
 * Class that implements a TCPMasterConnection.
 *
 * @author Dieter Wimberger
 * @version 1.2rc1 (09/11/2004)
 */
public class TCPMasterConnection {

  //instance attributes
  private Socket m_Socket;
  private int m_Timeout = Modbus.DEFAULT_TIMEOUT;
  private boolean m_Connected;

  private InetAddress m_Address;
  private int m_Port = Modbus.DEFAULT_PORT;

  //private int m_Retries = Modbus.DEFAULT_RETRIES;
  private ModbusTCPTransport m_ModbusTransport;

  /**
   * Constructs a <tt>TCPMasterConnection</tt> instance
   * with a given destination address.
   *
   * @param adr the destination <tt>InetAddress</tt>.
   */
  public TCPMasterConnection(InetAddress adr) {
    m_Address = adr;
  }//constructor

  /**
   * Opens this <tt>TCPMasterConnection</tt>.
   *
   * @throws Exception if there is a network failure.
   */
  public synchronized void connect()
      throws Exception {
    if(!m_Connected) {
      if(Modbus.debug) System.out.println("connect()");
      m_Socket = new Socket(m_Address, m_Port);
      setTimeout(m_Timeout);
      prepareTransport();
      m_Connected = true;
    }
  }//connect

  /**
   * Closes this <tt>TCPMasterConnection</tt>.
   */
  public void close() {
    if(m_Connected) {
      try {
        m_ModbusTransport.close();
      } catch (IOException ex) {
        if(Modbus.debug) System.out.println("close()");
      }
      m_Connected = false;
    }
  }//close

  /**
   * Returns the <tt>ModbusTransport</tt> associated with this
   * <tt>TCPMasterConnection</tt>.
   *
   * @return the connection's <tt>ModbusTransport</tt>.
   */
  public ModbusTransport getModbusTransport() {
    return m_ModbusTransport;
  }//getModbusTransport

  /**
   * Prepares the associated <tt>ModbusTransport</tt> of this
   * <tt>TCPMasterConnection</tt> for use.
   *
   * @throws IOException if an I/O related error occurs.
   */
  private void prepareTransport() throws IOException {
    if (m_ModbusTransport == null) {
      m_ModbusTransport = new ModbusTCPTransport(m_Socket);
    } else {
      m_ModbusTransport.setSocket(m_Socket);
    }
  }//prepareIO

  /**
   * Returns the timeout for this <tt>TCPMasterConnection</tt>.
   *
   * @return the timeout as <tt>int</tt>.
   */
  public int getTimeout() {
    return m_Timeout;
  }//getTimeout

  /**
   * Sets the timeout for this <tt>TCPMasterConnection</tt>.
   *
   * @param timeout the timeout as <tt>int</tt>.
   */
  public void setTimeout(int timeout) {
    m_Timeout = timeout;
    try {
      m_Socket.setSoTimeout(m_Timeout);
    } catch (IOException ex) {
      //handle?
    }
  }//setTimeout

  /**
   * Returns the destination port of this
   * <tt>TCPMasterConnection</tt>.
   *
   * @return the port number as <tt>int</tt>.
   */
  public int getPort() {
    return m_Port;
  }//getPort

  /**
   * Sets the destination port of this
   * <tt>TCPMasterConnection</tt>.
   * The default is defined as <tt>Modbus.DEFAULT_PORT</tt>.
   *
   * @param port the port number as <tt>int</tt>.
   */
  public void setPort(int port) {
    m_Port = port;
  }//setPort

  /**
   * Returns the destination <tt>InetAddress</tt> of this
   * <tt>TCPMasterConnection</tt>.
   *
   * @return the destination address as <tt>InetAddress</tt>.
   */
  public InetAddress getAddress() {
    return m_Address;
  }//getAddress

  /**
   * Sets the destination <tt>InetAddress</tt> of this
   * <tt>TCPMasterConnection</tt>.
   *
   * @param adr the destination address as <tt>InetAddress</tt>.
   */
  public void setAddress(InetAddress adr) {
    m_Address = adr;
  }//setAddress

  /**
   * Tests if this <tt>TCPMasterConnection</tt> is connected.
   *
   * @return <tt>true</tt> if connected, <tt>false</tt> otherwise.
   */
  public boolean isConnected() {
    return m_Connected;
  }//isConnected


}//class TCPMasterConnection