javax.crypto.spec

Class DESedeKeySpec

java.lang.Object

javax.crypto.spec.DESedeKeySpec

All Implemented Interfaces:

KeySpec

public class DESedeKeySpec
extends Object
implements KeySpec

This class is a transparent wrapper for DES-EDE (Triple-DES) keys, which are arrays of 24 bytes.

Since:

1.4

Field Summary

Fields

Modifier and Type	Field and Description
static int	DES_EDE_KEY_LEN The length of a triple-DES key, in bytes.

Constructor Summary

Constructors

Constructor and Description
DESedeKeySpec(byte[] key) Create a new DES-EDE key spec, copying the first 24 bytes from the byte array.
DESedeKeySpec(byte[] key, int offset) Create a new DES-EDE key spec, starting at offset in the byte array.

Method Summary

Methods

Modifier and Type	Method and Description
byte[]	getKey() Return the key as a byte array.
static boolean	isParityAdjusted(byte[] key, int offset) Returns whether or not the given key is parity adjusted; i.e. every byte in the key has an odd number of "1" bits.

Methods inherited from class java.lang.Object

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

Field Detail

DES_EDE_KEY_LEN

public static final int DES_EDE_KEY_LEN

The length of a triple-DES key, in bytes.

See Also:

Constant Field Values

Constructor Detail

DESedeKeySpec

public DESedeKeySpec(byte[] key)
              throws InvalidKeyException

Create a new DES-EDE key spec, copying the first 24 bytes from the byte array.

Parameters:

key - The key bytes.

Throws:

InvalidKeyException - If there are less than 24 bytes in the array.

DESedeKeySpec

public DESedeKeySpec(byte[] key,
             int offset)
              throws InvalidKeyException

Create a new DES-EDE key spec, starting at offset in the byte array. The first 24 bytes starting at offset are copied.

Parameters:

key - The key bytes.

offset - The offset into the byte array at which to begin.

Throws:

InvalidKeyException - If there are less than 24 bytes starting at offset.

Method Detail

isParityAdjusted

public static boolean isParityAdjusted(byte[] key,
                       int offset)
                                throws InvalidKeyException

Returns whether or not the given key is parity adjusted; i.e. every byte in the key has an odd number of "1" bits.

Parameters:

key - The key bytes, considered between [offset, offset+23]

offset - The offset into the byte array at which to begin.

Returns:

True if all bytes have an odd number of "1" bits.

Throws:

InvalidKeyException - If there are not enough bytes in the array.

getKey

public byte[] getKey()

Return the key as a byte array. This method does not copy the byte array.

Returns:

The key bytes.