DESKeySpec
public
class
DESKeySpec
extends Object
implements
KeySpec
| java.lang.Object | |
| ↳ | javax.crypto.spec.DESKeySpec |
This class specifies a DES key.
Summary
Constants | |
|---|---|
int |
DES_KEY_LEN
The constant which defines the length of a DES key in bytes. |
Public constructors | |
|---|---|
DESKeySpec(byte[] key)
Creates a DESKeySpec object using the first 8 bytes in
|
|
DESKeySpec(byte[] key, int offset)
Creates a DESKeySpec object using the first 8 bytes in
|
|
Public methods | |
|---|---|
byte[]
|
getKey()
Returns the DES key material. |
static
boolean
|
isParityAdjusted(byte[] key, int offset)
Checks if the given DES key material, starting at |
static
boolean
|
isWeak(byte[] key, int offset)
Checks if the given DES key material is weak or semi-weak. |
Inherited methods | |
|---|---|
Constants
DES_KEY_LEN
public static final int DES_KEY_LEN
The constant which defines the length of a DES key in bytes.
Constant Value: 8 (0x00000008)
Public constructors
DESKeySpec
public DESKeySpec (byte[] key)
Creates a DESKeySpec object using the first 8 bytes in
key as the key material for the DES key.
The bytes that constitute the DES key are those between
key[0] and key[7] inclusive.
| Parameters | |
|---|---|
key |
byte: the buffer with the DES key material. The first 8 bytes
of the buffer are copied to protect against subsequent modification. |
| Throws | |
|---|---|
NullPointerException |
if the given key material is
null |
InvalidKeyException |
if the given key material is shorter than 8 bytes. |
DESKeySpec
public DESKeySpec (byte[] key,
int offset)Creates a DESKeySpec object using the first 8 bytes in
key, beginning at offset inclusive,
as the key material for the DES key.
The bytes that constitute the DES key are those between
key[offset] and key[offset+7] inclusive.
| Parameters | |
|---|---|
key |
byte: the buffer with the DES key material. The first 8 bytes
of the buffer beginning at offset inclusive are copied
to protect against subsequent modification. |
offset |
int: the offset in key, where the DES key
material starts. |
| Throws | |
|---|---|
NullPointerException |
if the given key material is
null |
InvalidKeyException |
if the given key material, starting at
offset inclusive, is shorter than 8 bytes. |
Public methods
getKey
public byte[] getKey ()
Returns the DES key material.
| Returns | |
|---|---|
byte[] |
the DES key material. Returns a new array each time this method is called. |
isParityAdjusted
public static boolean isParityAdjusted (byte[] key,
int offset)Checks if the given DES key material, starting at offset
inclusive, is parity-adjusted.
| Parameters | |
|---|---|
key |
byte: the buffer with the DES key material. |
offset |
int: the offset in key, where the DES key
material starts. |
| Returns | |
|---|---|
boolean |
true if the given DES key material is parity-adjusted, false otherwise. |
| Throws | |
|---|---|
InvalidKeyException |
if the given key material is
null, or starting at offset inclusive, is
shorter than 8 bytes. |
isWeak
public static boolean isWeak (byte[] key,
int offset)Checks if the given DES key material is weak or semi-weak.
| Parameters | |
|---|---|
key |
byte: the buffer with the DES key material. |
offset |
int: the offset in key, where the DES key
material starts. |
| Returns | |
|---|---|
boolean |
true if the given DES key material is weak or semi-weak, false otherwise. |
| Throws | |
|---|---|
InvalidKeyException |
if the given key material is
null, or starting at offset inclusive, is
shorter than 8 bytes. |