uk.ac.starlink.ttools.func

Class Bits

java.lang.Object

uk.ac.starlink.ttools.func.Bits

public class Bits
extends Object

Bit manipulation functions.

Note that for bitwise AND, OR, XOR of integer values etc you can use the java bitwise operators "&", "|", "^".

Since:

4 Apr 2022

Author:

Mark Taylor

Method Summary

Modifier and Type	Method and Description
static int	bitCount(long i) Returns the number of set bits in the 64-bit two's complement representation of the integer argument.
static int	fromBinary(String binVal) Converts a string representing a binary number to its integer value.
static boolean	hasBit(long value, int bitIndex) Determines whether a given integer has a certain bit set to 1.
static String	toBinary(long value) Converts the integer argument to a binary string consisting only of 1s and 0s.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

hasBit

public static boolean hasBit(long value,
                             int bitIndex)

Determines whether a given integer has a certain bit set to 1.

Parameters:

value - integer whose bits are to be tested

bitIndex - index of bit to be tested in range 0..63, where 0 is the least significant bit

Returns:

true if bit is set; more or less equivalent to (value & 1L<<bitIndex) != 0

bitCount

public static int bitCount(long i)

Returns the number of set bits in the 64-bit two's complement representation of the integer argument.

Parameters:

i - integer value

Returns:

number of "1" bits in the binary representation of i

toBinary

public static String toBinary(long value)

Converts the integer argument to a binary string consisting only of 1s and 0s.

Parameters:

value - integer value

Returns:

binary representation of value

fromBinary

public static int fromBinary(String binVal)

Converts a string representing a binary number to its integer value.

Parameters:

binVal - binary representation of value

Returns:

integer value represented by binary string binVal