rkutil.java

Office格式转换代码

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package org.apache.poi.hssf.util;

/**
 * Utility class for helping convert RK numbers.
 *
 * @author Andrew C. Oliver (acoliver at apache dot org)
 * @author Glen Stampoultzis (glens at apache.org)
 * @author Rolf-J黵gen Moll
 *
 * @see org.apache.poi.hssf.record.MulRKRecord
 * @see org.apache.poi.hssf.record.RKRecord
 */
public class RKUtil
{
    private RKUtil()
    {
    }

    /**
     * Do the dirty work of decoding; made a private static method to
     * facilitate testing the algorithm
     */

    public static double decodeNumber(int number)
    {
        long raw_number = number;

        // mask off the two low-order bits, 'cause they're not part of
        // the number
        raw_number = raw_number >> 2;
        double rvalue = 0;

        if ((number & 0x02) == 0x02)
        {
            // ok, it's just a plain ol' int; we can handle this
            // trivially by casting
            rvalue = ( double ) (raw_number);
        }
        else
        {

            // also trivial, but not as obvious ... left shift the
            // bits high and use that clever static method in Double
            // to convert the resulting bit image to a double
            rvalue = Double.longBitsToDouble(raw_number << 34);
        }
        if ((number & 0x01) == 0x01)
        {

            // low-order bit says divide by 100, and so we do. Why?
            // 'cause that's what the algorithm says. Can't fight city
            // hall, especially if it's the city of Redmond
            rvalue /= 100;
        }

        return rvalue;
    }

}