com.tangosol.util
Class BitHelper

java.lang.Object
  com.tangosol.util.Base
      com.tangosol.util.BitHelper

Direct Known Subclasses:

ExternalizableHelper, PartitionSet

public class BitHelper
extends Base

A collection of methods for bit-based operations.

Author:

cp 2006.01.10 starting from the MemberSet implementation

Constructor Summary

BitHelper()

Method Summary

static int	countBits(byte b) Count the number of bits set in the passed integral value.
static int	countBits(int n) Count the number of bits set in the passed integral value.
static int	countBits(long l) Count the number of bits set in the passed integral value.
static int	indexOfLSB(byte b) Determine the least significant bit of the passed integral value.
static int	indexOfLSB(int n) Determine the least significant bit of the passed integral value.
static int	indexOfLSB(long l) Determine the least significant bit of the passed integral value.
static int	indexOfMSB(byte b) Determine the most significant bit of the passed integral value.
static int	indexOfMSB(int n) Determine the most significant bit of the passed integral value.
static int	indexOfMSB(long l) Determine the most significant bit of the passed integral value.
static String	toBitString(byte b) Convert a byte to a String of ones and zeros.
static String	toBitString(int n) Convert an int to a String of ones and zeros.
static String	toBitString(long l) Convert a long to a String of ones and zeros.

Constructor Detail

BitHelper

public BitHelper()

Method Detail

countBits

public static int countBits(byte b)

Count the number of bits set in the passed integral value.

Parameters:

b - a byte

Returns:

the number of bits set in the byte [0..8]

countBits

public static int countBits(int n)

Count the number of bits set in the passed integral value.

Parameters:

n - an int

Returns:

the number of bits set in the int [0..32]

countBits

public static int countBits(long l)

Count the number of bits set in the passed integral value.

Parameters:

l - a long

Returns:

the number of bits set in the long [0..64]

indexOfMSB

public static int indexOfMSB(byte b)

Determine the most significant bit of the passed integral value.

Parameters:

b - a byte

Returns:

-1 if no bits are set; otherwise, the bit position p of the most significant bit such that 1 << p is the most significant bit of b

indexOfMSB

public static int indexOfMSB(int n)

Determine the most significant bit of the passed integral value.

Parameters:

n - an int

Returns:

-1 if no bits are set; otherwise, the bit position p of the most significant bit such that 1 << p is the most significant bit of n

indexOfMSB

public static int indexOfMSB(long l)

Determine the most significant bit of the passed integral value.

Parameters:

l - a long

Returns:

-1 if no bits are set; otherwise, the bit position p of the most significant bit such that 1 << p is the most significant bit of l

indexOfLSB

public static int indexOfLSB(byte b)

Determine the least significant bit of the passed integral value.

Parameters:

b - a byte

Returns:

-1 if no bits are set; otherwise, the bit position p of the least significant bit such that 1 << p is the least significant bit of b

indexOfLSB

public static int indexOfLSB(int n)

Determine the least significant bit of the passed integral value.

Parameters:

n - an int

Returns:

-1 if no bits are set; otherwise, the bit position p of the least significant bit such that 1 << p is the least significant bit of n

indexOfLSB

public static int indexOfLSB(long l)

Determine the least significant bit of the passed integral value.

Parameters:

l - a long

Returns:

-1 if no bits are set; otherwise, the bit position p of the least significant bit such that 1 << p is the least significant bit of l

toBitString

public static String toBitString(byte b)

Convert a byte to a String of ones and zeros.

Parameters:

b - a byte

Returns:

a String of ones and zeros representing the byte value

toBitString

public static String toBitString(int n)

Convert an int to a String of ones and zeros.

Parameters:

n - an int

Returns:

a String of ones and zeros representing the int value

toBitString

public static String toBitString(long l)

Convert a long to a String of ones and zeros.

Parameters:

l - a long

Returns:

a String of ones and zeros representing the long value