//
//  PO_NetClient.java
//
//  WELD Java Client Persistent Object Management Package
//  Copyright Francis Chan (fchan@ic.eecs.berkeley.edu), 1997
//  University of California, Berkeley
//
//
//  This program is in the public domain.
//  Permission to use, copy, modify, and distribute this software
//  and its documentation for NON-COMMERCIAL purposes and
//  without fee is hereby granted, as long as credit is given.

import java.net.*;
import java.io.*;

/**
 *
 * PO_NetClient Class
 *
 * This is a class which handles network socket connections and
 * closings.
 * It is also where the remote server and port number is specified.
 *
 * @version 1.3 Nov 1996
 * @author  Francis Chan
 */

public class PO_NetClient{

  private OutputStream outStream = null;
  private String outStreamString = new String();
  //private String server = "yoyodyne.eecs.berkeley.edu";
  private String server;
  private Socket netSocket;

  /**
   * Port number for the data server
   */
  private int port;

  private boolean debugFlag = true;

  /**
   *
   * Constructor of a PO_NetClient
   * @param server  The name of the server to connect to
   * @param port    The port of the server to connect to
   */

  public PO_NetClient(String server, int port){

    this.server = server;
    this.port = port;
  }


  /**
   *
   * Method that opens a socket connection to the designated server.
   * (set to yoyodyne.eecs.berkeley.edu,
   *  port 701x right now)
   * Returns a socket if connection is completed,
   * null if not.
   *
   * Server and port number should/could be passed in in the future
   */

  public Socket openConnection()
  {

    DEBUG("connecting to port: " + port + " ...");

    try {
      netSocket = new Socket(server, port);
      DEBUG("Opened Port!!");
      return netSocket;
    } catch (Exception e) {
      System.out.println("Port can't be opened");
      e.printStackTrace();
      return null;
    }
  }

  /**
   *
   * Closes the network connection
   */

  public void closeConnection(Socket netSocket) {

    try {
      netSocket.close();
    } catch (Exception e) {
      System.out.println("Socket can't be closed!");
    }
  }


  /**
   *
   * Sends the message to the pre-designated network server
   *
   * @param message     Message to be sent
   */

  public void sendString(String message) {

    try {
      outStream = netSocket.getOutputStream();
    } catch (Exception e) {
      System.out.println("can't open output stream");
      e.printStackTrace();
    }

    try {
      for (int i=0; i<message.length(); i++) {
	outStream.write(message.charAt(i));
      }
    } catch (Exception e) {
      System.out.println("Out Stream Error! (Prepare Stream)");
      e.printStackTrace();
    }

  }


  /**
   *
   * Debug
   * Prints debugging statements if the debug flag is set to true
   *
   * @param debugStmt The debugging statement supplied
   */

  static protected void DEBUG(String debugStmt){

    if (PersistentObject.debugFlag == true) {
      System.out.println("PO_NetClient: " + debugStmt);
    }

  }

}