rkhelper.java

JAVA 文章管理系统源码

/*********************************************************************
*
*      Copyright (C) 2002 Andrew Khan
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
***************************************************************************/

package jxl.read.biff;

/**
 * Helper to convert an RK number into a double or an integer
 */
final class RKHelper
{
  /**
   * Private constructor to prevent instantiation
   */
  private RKHelper()
  {
  }

  /**
   * Converts excel's internal RK format into a double value
   *
   * @param rk the rk number in bits
   * @return the double representation
   */
  public static double getDouble(int rk)
  {
    if ((rk & 0x02) != 0)
    {
      int intval = rk >> 2;

      double value = (double) intval;
      if ((rk & 0x01) != 0)
      {
        value /= 100;
      }

      return value;
    }
    else
    {
      long valbits = (rk & 0xfffffffc);
      valbits <<= 32;
      double value = Double.longBitsToDouble(valbits);

      if ((rk & 0x01) != 0)
      {
        value /= 100;
      }

      return value;
    }
  }
}