java.security

Class KeyPairGeneratorSpi

java.lang.Object

java.security.KeyPairGeneratorSpi

Direct Known Subclasses:

KeyPairGenerator

public abstract class KeyPairGeneratorSpi
extends Object

This class defines the Service Provider Interface (SPI) for the KeyPairGenerator class, which is used to generate pairs of public and private keys.

All the abstract methods in this class must be implemented by each cryptographic service provider who wishes to supply the implementation of a key pair generator for a particular algorithm.

In case the client does not explicitly initialize the KeyPairGenerator (via a call to an initialize method), each provider must supply (and document) a default initialization. For example, the Sun provider uses a default modulus size (keysize) of 1024 bits.

Author:

Benjamin Renaud

See Also:

KeyPairGenerator, AlgorithmParameterSpec

Constructor Summary

Constructors

Constructor and Description
KeyPairGeneratorSpi()

Method Summary

Modifier and Type	Method and Description
abstract KeyPair	generateKeyPair() Generates a key pair.
void	initialize(AlgorithmParameterSpec params, SecureRandom random) Initializes the key pair generator using the specified parameter set and user-provided source of randomness.
abstract void	initialize(int keysize, SecureRandom random) Initializes the key pair generator for a certain keysize, using the default parameter set.

Methods inherited from class java.lang.Object

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

Constructor Detail

KeyPairGeneratorSpi

public KeyPairGeneratorSpi()

Method Detail

initialize

public abstract void initialize(int keysize,
                                SecureRandom random)

Initializes the key pair generator for a certain keysize, using the default parameter set.

Parameters:

keysize - the keysize. This is an algorithm-specific metric, such as modulus length, specified in number of bits.

random - the source of randomness for this generator.

Throws:

InvalidParameterException - if the keysize is not supported by this KeyPairGeneratorSpi object.

initialize

public void initialize(AlgorithmParameterSpec params,
                       SecureRandom random)
                throws InvalidAlgorithmParameterException

Initializes the key pair generator using the specified parameter set and user-provided source of randomness.

This concrete method has been added to this previously-defined abstract class. (For backwards compatibility, it cannot be abstract.) It may be overridden by a provider to initialize the key pair generator. Such an override is expected to throw an InvalidAlgorithmParameterException if a parameter is inappropriate for this key pair generator. If this method is not overridden, it always throws an UnsupportedOperationException.

Parameters:

params - the parameter set used to generate the keys.

random - the source of randomness for this generator.

Throws:

InvalidAlgorithmParameterException - if the given parameters are inappropriate for this key pair generator.

Since:

1.2

generateKeyPair

public abstract KeyPair generateKeyPair()

Generates a key pair. Unless an initialization method is called using a KeyPairGenerator interface, algorithm-specific defaults will be used. This will generate a new key pair every time it is called.

Returns:

the newly generated KeyPair