DESedeKeySpec

AI-generated Key Takeaways

• DESedeKeySpec specifies a DES-EDE (triple-DES) key using a 24-byte key material.

• It provides constructors to create a DESedeKeySpec object from a byte array containing the key material.

• You can retrieve the DES-EDE key using the getKey() method and check for parity adjustment using isParityAdjusted().

• A constant, DES_EDE_KEY_LEN, defines the key length as 24 bytes.

public class DESedeKeySpec extends Object
implements KeySpec

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

Constant Summary

int

DES_EDE_KEY_LEN

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

Public 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.

Public 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.

Inherited Method Summary

From class java.lang.Object

Object	clone() Creates and returns a copy of this Object.
boolean	equals(Object obj) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of Class that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long timeout, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait(long timeout) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object.

Constants

public static final int DES_EDE_KEY_LEN

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

Constant Value: 24

Public Constructors

public DESedeKeySpec (byte[] key)

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.

public 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.

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

Public Methods

public byte[] getKey ()

Returns the DES-EDE key.

Returns

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

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

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