/**
* Copyright (c) 2013, Will Szumski
*
* This file is part of formicidae.
*
* formicidae 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 3 of the License, or
* (at your option) any later version.
*
* formicidae 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 formicidae. If not, see <http://www.gnu.org/licenses/>.
*/
package org.cowboycoders.ant.utils;
/**
* Utilities for dealing with raw bits
* @author will
*
*/
public class BitUtils {
/**
* Calulcates index of left most bit
* for any positive integer
* @param number to check
* @return the index of the left most bit
*/
public static int getMaxBitIndex(int number) {
if (number < 0) {
throw new RuntimeException("negative numbers unsupported");
}
int maxBit = 0;
while((number = number >>> 1) >=0) {
maxBit++;
if (number == 0) {
break;
}
}
return maxBit;
}
/**
* Calculates index of left most zero before first bit
* for any positive integer
* @param number to check
* @return the index of the left most bit (zero based), -1 if no zeros
*/
public static int getMaxZeroBitIndex(int number) {
if (number < 0) {
throw new RuntimeException("negative numbers unsupported");
}
int maxBit = -1;
int mask = 1;
while(mask <= number) {
if((mask & number) != 0) {
break;
}
mask = mask << 1;
maxBit++;
}
return maxBit;
}
private BitUtils() {
}
}