API java : DESedeKeySpec

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 specifies a DES-EDE ("triple-DES") key.

Since:

1.4

Field Summary
static int	DES_EDE_KEY_LEN           The constant which defines the length of a DESede key in bytes.

 

Constructor Summary
DESedeKeySpec(byte[] key)           Creates a DESedeKeySpec object using the first 24 bytes in key as the key material for the DES-EDE key.
DESedeKeySpec(byte[] key, int offset)           Creates a DESedeKeySpec object using the first 24 bytes in key, beginning at offset inclusive, as the key material for the DES-EDE key.

 

Method Summary
byte[]	getKey()           Returns the DES-EDE key.
static boolean	isParityAdjusted(byte[] key, int offset)           Checks if the given DES-EDE key, starting at offset inclusive, is parity-adjusted.

 

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 constant which defines the length of a DESede key in bytes.

See Also:

Constant Field Values

DESedeKeySpec

public DESedeKeySpec(byte[] key)
              throws InvalidKeyException

Creates a DESedeKeySpec object using the first 24 bytes in key as the key material for the DES-EDE key.

The bytes that constitute the DES-EDE key are those between key[0] and key[23] inclusive

Parameters:

key - the buffer with the DES-EDE key material. The first 24 bytes of the buffer are copied to protect against subsequent modification.

Throws:

NullPointerException - if key is null.

InvalidKeyException - if the given key material is shorter than 24 bytes.

DESedeKeySpec

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

Creates a DESedeKeySpec object using the first 24 bytes in key, beginning at offset inclusive, as the key material for the DES-EDE key.

The bytes that constitute the DES-EDE key are those between key[offset] and key[offset+23] inclusive.

Parameters:

key - the buffer with the DES-EDE key material. The first 24 bytes of the buffer beginning at offset inclusive are copied to protect against subsequent modification.

offset - the offset in key, where the DES-EDE key material starts.

Throws:

NullPointerException - if key is null.

InvalidKeyException - if the given key material, starting at offset inclusive, is shorter than 24 bytes

getKey

public byte[] getKey()

Returns the DES-EDE key.

Returns:

the DES-EDE key. Returns a new array each time this method is called.

isParityAdjusted

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

Checks if the given DES-EDE key, starting at offset inclusive, is parity-adjusted.

Parameters:

key - a byte array which holds the key value

offset - the offset into the byte array

Returns:

true if the given DES-EDE key is parity-adjusted, false otherwise

Throws:

NullPointerException - if key is null.

InvalidKeyException - if the given key material, starting at offset inclusive, is shorter than 24 bytes