Module java.base

Package javax.crypto

Class KeyGeneratorSpi

java.lang.Object

javax.crypto.KeyGeneratorSpi

public abstract class KeyGeneratorSpi
extends Object

This class defines the Service Provider Interface (SPI) for the KeyGenerator class. All the abstract methods in this class must be implemented by each cryptographic service provider who wishes to supply the implementation of a key generator for a particular algorithm.

In case the client does not explicitly initialize the KeyGenerator (via a call to an init method), each provider must supply (and document) a default initialization. See the Keysize Restriction sections of the JDK Providers document for information on the KeyGenerator defaults used by JDK providers. However, note that defaults may vary across different providers. Additionally, the default value for a provider may change in a future version. Therefore, it is recommended to explicitly initialize the KeyGenerator instead of relying on provider-specific defaults.

Since:

1.4

See Also:

• SecretKey

Constructor Summary

Constructors

Constructor	Description
KeyGeneratorSpi()	Constructor for subclasses to call.

Method Summary

Modifier and Type	Method	Description
protected abstract SecretKey	engineGenerateKey()	Generates a secret key.
protected abstract void	engineInit(int keysize, SecureRandom random)	Initializes this key generator for a certain keysize, using the given source of randomness.
protected abstract void	engineInit(SecureRandom random)	Initializes the key generator.
protected abstract void	engineInit(AlgorithmParameterSpec params, SecureRandom random)	Initializes the key generator with the specified parameter set and a user-provided source of randomness.

Methods declared in class java.lang.Object

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

Constructor Details

KeyGeneratorSpi

public KeyGeneratorSpi()

Constructor for subclasses to call.

Method Details

engineInit

protected abstract void engineInit(SecureRandom random)

Initializes the key generator.

Parameters:

random - the source of randomness for this generator

engineInit

protected abstract void engineInit(AlgorithmParameterSpec params,
 SecureRandom random)
                            throws InvalidAlgorithmParameterException

Initializes the key generator with the specified parameter set and a user-provided source of randomness.

Parameters:

params - the key generation parameters

random - the source of randomness for this key generator

Throws:

InvalidAlgorithmParameterException - if params is inappropriate for this key generator

engineInit

protected abstract void engineInit(int keysize,
 SecureRandom random)

Initializes this key generator for a certain keysize, using the given source of randomness.

Parameters:

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

random - the source of randomness for this key generator

Throws:

InvalidParameterException - if the keysize is wrong or not supported.

engineGenerateKey

protected abstract SecretKey engineGenerateKey()

Generates a secret key.

Returns:

the new key