public
class
SecretKeySpec
extends Object
implements
KeySpec,
SecretKey
java.lang.Object | |
↳ | javax.crypto.spec.SecretKeySpec |
This class specifies a secret key in a provider-independent fashion.
It can be used to construct a SecretKey
from a byte array,
without having to go through a (provider-based)
SecretKeyFactory
.
This class is only useful for raw secret keys that can be represented as a byte array and have no key parameters associated with them, e.g., DES or Triple DES keys.
See also:
Inherited constants |
---|
From
interface
javax.crypto.SecretKey
|
From
interface
java.security.Key
|
Public constructors | |
---|---|
SecretKeySpec(byte[] key, String algorithm)
Constructs a secret key from the given byte array. |
|
SecretKeySpec(byte[] key, int offset, int len, String algorithm)
Constructs a secret key from the given byte array, using the first
|
Public methods | |
---|---|
boolean
|
equals(Object obj)
Tests for equality between the specified object and this object. |
String
|
getAlgorithm()
Returns the name of the algorithm associated with this secret key. |
byte[]
|
getEncoded()
Returns the key material of this secret key. |
String
|
getFormat()
Returns the name of the encoding format for this secret key. |
int
|
hashCode()
Calculates a hash code value for the object. |
Inherited methods | |
---|---|
From
class
java.lang.Object
| |
From
interface
java.security.Key
|
SecretKeySpec (byte[] key, String algorithm)
Constructs a secret key from the given byte array.
This constructor does not check if the given bytes indeed specify a
secret key of the specified algorithm. For example, if the algorithm is
DES, this constructor does not check if key
is 8 bytes
long, and also does not check for weak or semi-weak keys.
In order for those checks to be performed, an algorithm-specific
key specification class (in this case:
DESKeySpec
)
should be used.
Parameters | |
---|---|
key |
byte :
the key material of the secret key. The contents of
the array are copied to protect against subsequent modification. |
algorithm |
String :
the name of the secret-key algorithm to be associated
with the given key material.
See Appendix A in the
Java Cryptography Architecture Reference Guide
for information about standard algorithm names. |
Throws | |
---|---|
IllegalArgumentException |
if algorithm
is null or key is null or empty.
|
SecretKeySpec (byte[] key, int offset, int len, String algorithm)
Constructs a secret key from the given byte array, using the first
len
bytes of key
, starting at
offset
inclusive.
The bytes that constitute the secret key are
those between key[offset]
and
key[offset+len-1]
inclusive.
This constructor does not check if the given bytes indeed specify a
secret key of the specified algorithm. For example, if the algorithm is
DES, this constructor does not check if key
is 8 bytes
long, and also does not check for weak or semi-weak keys.
In order for those checks to be performed, an algorithm-specific key
specification class (in this case:
DESKeySpec
)
must be used.
Parameters | |
---|---|
key |
byte :
the key material of the secret key. The first
len bytes of the array beginning at
offset inclusive are copied to protect
against subsequent modification. |
offset |
int :
the offset in key where the key material
starts. |
len |
int :
the length of the key material. |
algorithm |
String :
the name of the secret-key algorithm to be associated
with the given key material.
See Appendix A in the
Java Cryptography Architecture Reference Guide
for information about standard algorithm names. |
Throws | |
---|---|
IllegalArgumentException |
if algorithm
is null or key is null, empty, or too short,
i.e. key.length-offset |
ArrayIndexOutOfBoundsException |
is thrown if
offset or len index bytes outside the
key .
|
boolean equals (Object obj)
Tests for equality between the specified object and this object. Two SecretKeySpec objects are considered equal if they are both SecretKey instances which have the same case-insensitive algorithm name and key encoding.
Parameters | |
---|---|
obj |
Object :
the object to test for equality with this object. |
Returns | |
---|---|
boolean |
true if the objects are considered equal, false if
obj is null or otherwise.
|
String getAlgorithm ()
Returns the name of the algorithm associated with this secret key.
Returns | |
---|---|
String |
the secret key algorithm. |
byte[] getEncoded ()
Returns the key material of this secret key.
Returns | |
---|---|
byte[] |
the key material. Returns a new array each time this method is called. |
String getFormat ()
Returns the name of the encoding format for this secret key.
Returns | |
---|---|
String |
the string "RAW". |
int hashCode ()
Calculates a hash code value for the object. Objects that are equal will also have the same hashcode.
Returns | |
---|---|
int |
a hash code value for this object. |