java.security

Class KeyFactory

java.lang.Object

java.security.KeyFactory

public class KeyFactory
extends Object

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.

Key factories are bi-directional. That is, they allow you 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.

Multiple compatible key specifications may exist for the same key. A key factory can be used to translate between compatible key specifications.

Since:

1.2

Author:

Jan Luehe

See Also:

Key, PublicKey, PrivateKey, KeySpec

Constructor Summary

Constructors

Constructor and Description
KeyFactory()

Method Summary

Modifier and Type	Method and Description
PrivateKey	generatePrivate(KeySpec keySpec) Generates a private key object from the provided key specification (key material).
PublicKey	generatePublic(KeySpec keySpec) Generates a public key object from the provided key specification (key material).
String	getAlgorithm() Gets the name of the algorithm associated with this KeyFactory.
static KeyFactory	getInstance(String algorithm) Returns a KeyFactory object that converts public/private keys of the specified algorithm.

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

KeyFactory

public KeyFactory()

Method Detail

generatePrivate

public final PrivateKey generatePrivate(KeySpec keySpec)
                                 throws InvalidKeySpecException

Generates a private key object from the provided key specification (key material).

Parameters:

keySpec - the specification (key material) of the private key.

Returns:

the private key.

Throws:

InvalidKeySpecException - if the given key specification is inappropriate for this key factory to produce a private key.

generatePublic

public final PublicKey generatePublic(KeySpec keySpec)
                               throws InvalidKeySpecException

Generates a public key object from the provided key specification (key material).

Parameters:

keySpec - the specification (key material) of the public key.

Returns:

the public key.

Throws:

InvalidKeySpecException - if the given key specification is inappropriate for this key factory to produce a public key.

getAlgorithm

public final String getAlgorithm()

Gets the name of the algorithm associated with this KeyFactory.

Returns:

the name of the algorithm associated with this KeyFactory

getInstance

public static KeyFactory getInstance(String algorithm)
                              throws NoSuchAlgorithmException

Returns a KeyFactory object that converts public/private keys of the specified algorithm.

Parameters:

algorithm - the name of the requested key algorithm. See the KeyFactory section in the Java Security Standard Algorithm Names Specification for information about standard algorithm names. Consult the release documentation for your implementation to see which algorithms are supported.

Returns:

the new KeyFactory object.

Throws:

NoSuchAlgorithmException - if the KeyFactorySpi has no implementation for the specified algorithm.