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javax.crypto
public class: SecretKeyFactory [javadoc | source]
java.lang.Object
   javax.crypto.SecretKeyFactory
This class represents a factory for secret keys.

Key factories are used to convert keys (opaque cryptographic keys of type Key) into key specifications (transparent representations of the underlying key material), and vice versa. Secret key factories operate only on secret (symmetric) keys.

Key factories are bi-directional, i.e., they allow to build an opaque key object from a given key specification (key material), or to retrieve the underlying key material of a key object in a suitable format.

Application developers should refer to their provider's documentation to find out which key specifications are supported by the generateSecret and getKeySpec methods. For example, the DES secret-key factory supplied by the "SunJCE" provider supports DESKeySpec as a transparent representation of DES keys, and that provider's secret-key factory for Triple DES keys supports DESedeKeySpec as a transparent representation of Triple DES keys.

Every implementation of the Java platform is required to support the following standard SecretKeyFactory algorithms:

These algorithms are described in the SecretKeyFactory section of the Java Cryptography Architecture Standard Algorithm Name Documentation. Consult the release documentation for your implementation to see if any other algorithms are supported.
Constructor:
 protected SecretKeyFactory(SecretKeyFactorySpi keyFacSpi,
    Provider provider,
    String algorithm) 
    Creates a SecretKeyFactory object.
    Parameters:
    keyFacSpi - the delegate
    provider - the provider
    algorithm - the secret-key algorithm
Method from javax.crypto.SecretKeyFactory Summary:
generateSecret,   getAlgorithm,   getInstance,   getInstance,   getInstance,   getKeySpec,   getProvider,   translateKey
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from javax.crypto.SecretKeyFactory Detail:
 public final SecretKey generateSecret(KeySpec keySpec) throws InvalidKeySpecException 
    Generates a SecretKey object from the provided key specification (key material).
 public final String getAlgorithm() 
    Returns the algorithm name of this SecretKeyFactory object.

    This is the same name that was specified in one of the getInstance calls that created this SecretKeyFactory object.

 public static final SecretKeyFactory getInstance(String algorithm) throws NoSuchAlgorithmException 
    Returns a SecretKeyFactory object that converts secret keys of the specified algorithm.

    This method traverses the list of registered security Providers, starting with the most preferred Provider. A new SecretKeyFactory object encapsulating the SecretKeyFactorySpi implementation from the first Provider that supports the specified algorithm is returned.

    Note that the list of registered providers may be retrieved via the Security.getProviders() method.

 public static final SecretKeyFactory getInstance(String algorithm,
    String provider) throws NoSuchAlgorithmException, NoSuchProviderException 
    Returns a SecretKeyFactory object that converts secret keys of the specified algorithm.

    A new SecretKeyFactory object encapsulating the SecretKeyFactorySpi implementation from the specified provider is returned. The specified provider must be registered in the security provider list.

    Note that the list of registered providers may be retrieved via the Security.getProviders() method.

 public static final SecretKeyFactory getInstance(String algorithm,
    Provider provider) throws NoSuchAlgorithmException 
    Returns a SecretKeyFactory object that converts secret keys of the specified algorithm.

    A new SecretKeyFactory object encapsulating the SecretKeyFactorySpi implementation from the specified Provider object is returned. Note that the specified Provider object does not have to be registered in the provider list.

 public final KeySpec getKeySpec(SecretKey key,
    Class keySpec) throws InvalidKeySpecException 
    Returns a specification (key material) of the given key object in the requested format.
 public final Provider getProvider() 
    Returns the provider of this SecretKeyFactory object.
 public final SecretKey translateKey(SecretKey key) throws InvalidKeyException 
    Translates a key object, whose provider may be unknown or potentially untrusted, into a corresponding key object of this secret-key factory.