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 bidirectional. 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. For example, a DSA public key may be specified using DSAPublicKeySpec
or X509EncodedKeySpec
. A key factory can be used to translate between compatible key specifications.
The following is an example of how to use a key factory in order to instantiate a DSA public key from its encoding. Assume Alice has received a digital signature from Bob. Bob also sent her his public key (in encoded format) to verify his signature. Alice then performs the following actions:
X509EncodedKeySpec bobPubKeySpec = new X509EncodedKeySpec(bobEncodedPubKey); KeyFactory keyFactory = KeyFactory.getInstance("DSA"); PublicKey bobPubKey = keyFactory.generatePublic(bobPubKeySpec); Signature sig = Signature.getInstance("DSA"); sig.initVerify(bobPubKey); sig.update(data); sig.verify(signature);
Every implementation of the Java platform is required to support the following standard KeyFactory
algorithms:
DiffieHellman
DSA
RSA
These algorithms are described in the
KeyFactory sectionof the Java Security Standard Algorithm Names Specification. Consult the release documentation for your implementation to see if any other algorithms are supported.
Constructors
protected
Creates a KeyFactory
object.
Generates a private key object from the provided key specification (key material).
Generates a public key object from the provided key specification (key material).
Gets the name of the algorithm associated with this KeyFactory
.
Returns a KeyFactory
object that converts public/private keys of the specified algorithm.
Returns a KeyFactory
object that converts public/private keys of the specified algorithm.
Returns a KeyFactory
object that converts public/private keys of the specified algorithm.
Returns a specification (key material) of the given key object.
Returns the provider of this key factory object.
Translates a key object, whose provider may be unknown or potentially untrusted, into a corresponding key object of this key factory.
Methods declared in class java.lang.Objectclone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Creates a KeyFactory
object.
keyFacSpi
- the delegate
provider
- the provider
algorithm
- the name of the algorithm to associate with this KeyFactory
Returns a
KeyFactory
object that converts public/private keys of the specified algorithm.
This method traverses the list of registered security providers, starting with the most preferred provider. A new KeyFactory
object encapsulating the KeyFactorySpi
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.
jdk.security.provider.preferred
Security
property to determine the preferred provider order for the specified algorithm. This may be different from the order of providers returned by Security.getProviders()
.
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.
KeyFactory
object
NoSuchAlgorithmException
- if no Provider
supports a KeyFactorySpi
implementation for the specified algorithm
NullPointerException
- if algorithm
is null
Returns a
KeyFactory
object that converts public/private keys of the specified algorithm.
A new KeyFactory
object encapsulating the KeyFactorySpi
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.
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.
provider
- the name of the provider.
KeyFactory
object
IllegalArgumentException
- if the provider name is null
or empty
NoSuchAlgorithmException
- if a KeyFactorySpi
implementation for the specified algorithm is not available from the specified provider
NoSuchProviderException
- if the specified provider is not registered in the security provider list
NullPointerException
- if algorithm
is null
Returns a
KeyFactory
object that converts public/private keys of the specified algorithm.
A new KeyFactory
object encapsulating the KeyFactorySpi
implementation from the specified provider is returned. Note that the specified provider does not have to be registered in the provider list.
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.
provider
- the provider.
KeyFactory
object
IllegalArgumentException
- if the specified provider is null
NoSuchAlgorithmException
- if a KeyFactorySpi
implementation for the specified algorithm is not available from the specified Provider
object
NullPointerException
- if algorithm
is null
Returns the provider of this key factory object.
()
Gets the name of the algorithm associated with this KeyFactory
.
KeyFactory
Generates a public key object from the provided key specification (key material).
keySpec
- the specification (key material) of the public key.
InvalidKeySpecException
- if the given key specification is inappropriate for this key factory to produce a public key.
Generates a private key object from the provided key specification (key material).
keySpec
- the specification (key material) of the private key.
InvalidKeySpecException
- if the given key specification is inappropriate for this key factory to produce a private key.
Returns a specification (key material) of the given key object. keySpec
identifies the specification class in which the key material should be returned. It could, for example, be DSAPublicKeySpec.class
, to indicate that the key material should be returned in an instance of the DSAPublicKeySpec
class.
T
- the type of the key specification to be returned
key
- the key.
keySpec
- the specification class in which the key material should be returned.
InvalidKeySpecException
- if the requested key specification is inappropriate for the given key, or the given key cannot be processed (e.g., the given key has an unrecognized algorithm or format).
Translates a key object, whose provider may be unknown or potentially untrusted, into a corresponding key object of this key factory.
key
- the key whose provider is unknown or untrusted.
InvalidKeyException
- if the given key cannot be processed by this key factory.
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4