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. |