Java Bit Count countBitsSet(int bitfield)

Description

count Bits Set

License

Open Source License

Declaration

public static int countBitsSet(int bitfield) 

Method Source Code

//package com.java2s;
/******************************************************************************
 * Copyright (c) 2004-2008 Whirlwind Match Limited. All rights reserved.
 *
 * This is open source software; you can use, redistribute and/or modify
 * it under the terms of the Open Software Licence v 3.0 as published by the 
 * Open Source Initiative./* ww w  .  j a v  a2s .  c  o m*/
 *
 * You should have received a copy of the Open Software Licence along with this
 * application. if not, contact the Open Source Initiative (www.opensource.org)
 *****************************************************************************/

public class Main {
    public static int countBitsSet(int bitfield) {
        int count = 0;
        for (short i = 0; i < Integer.SIZE; i++) {
            if ((bitfield & 0x01) != 0) {
                count++;
            }
            bitfield >>>= 1;
        }
        return count;
    }

    public static int countBitsSet(long bitfield) {
        int count = 0;
        for (short i = 0; i < Long.SIZE; i++) {
            if ((bitfield & 0x01) != 0) {
                count++;
            }
            bitfield >>>= 1;
        }
        return count;
    }
}

Related

1. countBits(int x)
2. countBits(long num)
3. countBits(long value)
4. countBitsInMask(int mask)
5. countBitsNeeded(int value)