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package org.apache.poi.hssf.util;
/**
* Utility class for helping convert RK numbers.
*
* @see org.apache.poi.hssf.record.MulRKRecord
* @see org.apache.poi.hssf.record.RKRecord
*/
public final class RKUtil {
private RKUtil() {
// no instances of this class
}
/**
* 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 = 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;
}
}