global.java

移动Agent编程工具Naplet

package naplet.nsocket;

import java.util.*;
import java.math.BigInteger;

/**
 * This class contains some of constants used in this package
 * <p>Title: </p>
 * <p>Description: </p>
 * <p>Copyright: Copyright (c) 2003</p>
 * <p>Company: </p>
 * @author Xiliang Zhong
 * @version 1.0
 */
public class Global
{

  /** states of current NSocket */
  public static final int SUSPENDED_LOCAL = 0;
  public static final int SUSPENDED_REMOTE = 0;
  public static final int RESUMED = 2;
  public static final int CLOSED = 3;

  /** the peer is suspending */
  public static final int SUSPEND_ACKWAIT = 4;
  public static final int SUSPEND_SENT = 5;
  public static final int SUSPEND_ACK_SEND = 6;
  public static final int SUSPEND_ACK_RCD = 7;
  public static final int HALF_RESUMED = 8;

  public static final int SUSPENDED = 0;

  /** Type of current socket */
  public static final int TRANSIENT = 0;
  public static final int PERSISTENT = 1;

  public static final int BUFFER_SIZE = 2048000;

  public static final String ACKMSG = "AckMsg:";
  public static final String ACK_WAIT_MSG = "AckWaitMsg:";
  public static final String ACK_STOP_RESUME = "AckStopResume";

  public static final int HIGH_PRIORITY = 1;
  public static final int LOW_PRIORITY = 2;

  /** port used by socket server of the control channel. can be changed
   * by socket controller */
      // public static int CONTROL_PORT = 5001;

  /** port used by some test application */
  public static int TCPPORT = 3868;

  /** port used by UDP server, if only one server, then use the port; if more
   * than one, the next one will use UDPPORT+1,the next UDPPORT+2, and so on*/
//  public static final int UDPPORT = 8683;

  /** time out value for UDP in mili seconds*/
  public static final int UDPTIMEOUT = 4000;

  public static final int UDPRETRY = 3;

  /** length of message send between client and server, for both tcp and udp*/
  public static final int MESSLEN = 256;

  /** Message displayed when nothing found*/
  public static final String NOTFOUND = "not found";

  /** query by author name*/
  public static final int AUTHOR = 1;

  /** query by book name*/
  public static final int NAME = 2;

  /** query by book number*/
  public static final int NUMBER = 3;

  /** unkown query */
  public static final int UNKNOWN = -1;

  /** use for Diffie-Hellman key exchange, */
  public static final BigInteger N = new BigInteger( "999" );

  public static final BigInteger G = new BigInteger( "2" );

  public static final int KEYSIZE = 8;

  /**
   * Generate a socket ID for NapletSocket
   * @return
   */
  public static String generateID()
  {
    return String.valueOf( System.currentTimeMillis() ) + "-" +
        String.valueOf( random.nextInt() ) + "-" + String.valueOf( counter++ );

  }

  /**
   * seed used by the ID generator
   */
  private static Random random = new Random();

  /**
   * counter used by the ID generator
   */
  private static int counter = 0;
}