doublevalue.java

一个非常有用的操作MCRSOFT EXCEL文件的工具。可以用JAVA方便的新建

/*********************************************************************
*
*      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.biff.formula;

import common.Logger;

import jxl.Cell;
import jxl.biff.DoubleHelper;

/**
 * A cell reference in a formula
 */
class DoubleValue extends NumberValue implements ParsedThing
{
  /**
   * The logger
   */
  private static Logger logger = Logger.getLogger(DoubleValue.class);

  /**
   * The value of this double in the formula
   */
  private double value;

  /**
   * Constructor
   */
  public DoubleValue()
  {
  }

  /**
   * Constructor - invoked when writing an integer value that's out
   * of range for a short
   */
  DoubleValue(double v)
  {
    value = v;
  }

  /**
   * Constructor for a double value when reading from a string
   */
  public DoubleValue(String s)
  {
    try
    {
      value = Double.parseDouble(s);
    }
    catch (NumberFormatException e)
    {
      logger.warn(e, e);
      value = 0;
    }
  }

  /** 
   * Reads the ptg data from the array starting at the specified position
   *
   * @param data the RPN array
   * @param pos the current position in the array, excluding the ptg identifier
   * @return the number of bytes read
   */
  public int read(byte[] data, int pos)
  {
    value = DoubleHelper.getIEEEDouble(data, pos);

    return 8;
  }

  /**
   * Gets the token representation of this item in RPN
   *
   * @return the bytes applicable to this formula
   */
  byte[] getBytes()
  {
    byte[] data = new byte[9];
    data[0] = Token.DOUBLE.getCode();

    DoubleHelper.getIEEEBytes(value, data, 1);

    return data;
  }

  public double getValue()
  {
    return value;
  }
}