Package javacardx.framework.math

Class ParityBit

java.lang.Object

javacardx.framework.math.ParityBit

public final class ParityBit
extends Object

The ParityBit class is a utility to assist with DES key parity bit generation.

Since:

2.2.2

Constructor Summary

Constructors

Constructor	Description
ParityBit()	Intended to be package visible.

Method Summary

Modifier and Type	Method	Description
static void	set(byte[] bArray, short bOff, short bLen, boolean isEven)	Inserts the computed parity bit of the specified type as the last bit(LSB) in each of the bytes of the specified byte array.

Methods inherited from class java.lang.Object

equals

Constructor Detail

ParityBit

public ParityBit()

Intended to be package visible. Retain for compatibility

Method Detail

set

public static void set(byte[] bArray,
                       short bOff,
                       short bLen,
                       boolean isEven)

Inserts the computed parity bit of the specified type as the last bit(LSB) in each of the bytes of the specified byte array. The parity is computed over the first(MS) 7 bits of each byte. The incoming last bit of each byte is ignored.

Note:

• If bOff or bLen is negative an ArrayIndexOutOfBoundsException exception is thrown.
• If bLen parameter is equal to 0 no parity bits are inserted.
• If bOff+bLen is greater than bArray.length, the length of the bArray array a ArrayIndexOutOfBoundsException exception is thrown and no parity bits are inserted.
• If bArray parameter is null a NullPointerException exception is thrown.

Parameters:

bArray - input/output byte array

bOff - offset within byte array to start setting parity on

bLen - byte length of input/output bytes

isEven - true if even parity is required and false if odd parity is required

Throws:

NullPointerException - if bArray is null

ArrayIndexOutOfBoundsException - if accessing the input array would cause access of data outside array bounds or if bLen is negative