unsignedinteger32.java

这是linux下ssl vpn的实现程序

/*
 *  SSL-Explorer
 *
 *  Copyright (C) 2003-2006 3SP LTD. All Rights Reserved
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version 2 of
 *  the License, or (at your option) any later version.
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public
 *  License along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
			
package com.maverick.crypto.io;

/**
 * This class provides a 32bit unsigned integer.
 *
 * @author Lee David Painter
 * @version $Revision: 1.2 $
 */
public class UnsignedInteger32 {

  /** The maximum value of a 32bit unsigned integer */
  public final static long MAX_VALUE = 0xffffffffL;

  /** The minimum value of a 32bit unsigned integer */
  public final static long MIN_VALUE = 0;
  private Long value;

  /**
   * Creates a new UnsignedInteger32 object.
   *
   * @param a
   *
   * @throws NumberFormatException
   */
  public UnsignedInteger32(long a) {
    if ( (a < MIN_VALUE) || (a > MAX_VALUE)) {
      throw new NumberFormatException();
    }

    value = new Long(a);
  }

  /**
   * Creates a new UnsignedInteger32 object.
   *
   * @param a
   *
   * @throws NumberFormatException
   */
  public UnsignedInteger32(String a) throws NumberFormatException {

    long longValue = Long.parseLong(a);

    if ( (longValue < MIN_VALUE) || (longValue > MAX_VALUE)) {
      throw new NumberFormatException();
    }

    value = new Long(longValue);
  }

  /**
   *
   *
   * @return
   */
  public int intValue() {
    return (int) value.longValue();
  }

  /**
   * Returns the long value of this unsigned integer.
   *
   * @return
   */
  public long longValue() {
    return value.longValue();
  }


  /**
   * Returns a String representation of the unsigned integer.
   *
   * @return
   */
  public String toString() {
    return value.toString();
  }

  /**
   * Returns the objects hash code.
   *
   * @return
   */
  public int hashCode() {
    return value.hashCode();
  }

  /**
   * Compares an object.
   *
   * @param o
   *
   * @return
   */
  public boolean equals(Object o) {
    if (! (o instanceof UnsignedInteger32)) {
      return false;
    }

    return ( ( (UnsignedInteger32) o).value.equals(this.value));
  }

  /**
   * Add two unsigned integers together.
   *
   * @param x
   * @param y
   *
   * @return
   */
  public static UnsignedInteger32 add(UnsignedInteger32 x, UnsignedInteger32 y) {
    return new UnsignedInteger32(x.longValue() + y.longValue());
  }

  /**
   * Add an int to an unsigned integer.
   *
   * @param x
   * @param y
   *
   * @return
   */
  public static UnsignedInteger32 add(UnsignedInteger32 x, int y) {
    return new UnsignedInteger32(x.longValue() + y);
  }
}