java.security

Class KeyPairGenerator

public abstract class KeyPairGenerator extends KeyPairGeneratorSpi

KeyPairGenerator is a class used to generate key-pairs for a security algorithm.

The KeyPairGenerator is created with the getInstance() Factory methods. It is used to generate a pair of public and private keys for a specific algorithm and associate this key-pair with the algorithm parameters it was initialized with.

Constructor Summary
protected	KeyPairGenerator(String algorithm) Constructs a new instance of `KeyPairGenerator`.

Method Summary
KeyPair	generateKeyPair() Generates a new "DSA" {@link KeyPair} from the "GNU" security provider.
KeyPair	genKeyPair() Generates a new "DSA" {@link KeyPair} from the "GNU" security provider.
String	getAlgorithm() Returns the name of the algorithm used.
static KeyPairGenerator	getInstance(String algorithm) Returns a new instance of `KeyPairGenerator` which generates key-pairs for the specified algorithm.
static KeyPairGenerator	getInstance(String algorithm, String provider) Returns a new instance of `KeyPairGenerator` which generates key-pairs for the specified algorithm from a named provider.
static KeyPairGenerator	getInstance(String algorithm, Provider provider) Returns a new instance of `KeyPairGenerator` which generates key-pairs for the specified algorithm from a designated {@link Provider}.
Provider	getProvider() Returns the {@link Provider} of this instance.
void	initialize(int keysize) Initializes this instance for the specified key size.
void	initialize(int keysize, SecureRandom random) Initializes this instance for the specified key size and {@link SecureRandom}.
void	initialize(AlgorithmParameterSpec params) Initializes this instance with the specified {@link AlgorithmParameterSpec}.
void	initialize(AlgorithmParameterSpec params, SecureRandom random) Initializes this instance with the specified {@link AlgorithmParameterSpec} and {@link SecureRandom}.

Constructor Detail

KeyPairGenerator

protected KeyPairGenerator(String algorithm)

Constructs a new instance of KeyPairGenerator.

Parameters: algorithm the algorithm to use.

Method Detail

generateKeyPair

public KeyPair generateKeyPair()

Generates a new "DSA" {@link KeyPair} from the "GNU" security provider.

This method generates a unique key pair each time it is called.

Returns: a new unique {@link KeyPair}.

genKeyPair

public final KeyPair genKeyPair()

Generates a new "DSA" {@link KeyPair} from the "GNU" security provider.

This method generates a unique key-pair each time it is called.

Returns: a new unique {@link KeyPair}.

Since: 1.2

getAlgorithm

public String getAlgorithm()

Returns the name of the algorithm used.

Returns: the name of the algorithm used.

getInstance

public static KeyPairGenerator getInstance(String algorithm)

Returns a new instance of KeyPairGenerator which generates key-pairs for the specified algorithm.

Parameters: algorithm the name of the algorithm to use.

Returns: a new instance repesenting the desired algorithm.

Throws: NoSuchAlgorithmException if the algorithm is not implemented by any provider. IllegalArgumentException if algorithm is null or is an empty string.

getInstance

public static KeyPairGenerator getInstance(String algorithm, String provider)

Returns a new instance of KeyPairGenerator which generates key-pairs for the specified algorithm from a named provider.

Parameters: algorithm the name of the algorithm to use. provider the name of a {@link Provider} to use.

Returns: a new instance repesenting the desired algorithm.

Throws: NoSuchAlgorithmException if the algorithm is not implemented by the named provider. NoSuchProviderException if the named provider was not found. IllegalArgumentException if either algorithm or provider is null or empty.

getInstance

public static KeyPairGenerator getInstance(String algorithm, Provider provider)

Returns a new instance of KeyPairGenerator which generates key-pairs for the specified algorithm from a designated {@link Provider}.

Parameters: algorithm the name of the algorithm to use. provider the {@link Provider} to use.

Returns: a new insatnce repesenting the desired algorithm.

Throws: NoSuchAlgorithmException if the algorithm is not implemented by the {@link Provider}. IllegalArgumentException if either algorithm or provider is null, or if algorithm is an empty string.

Since: 1.4

getProvider

public final Provider getProvider()

Returns the {@link Provider} of this instance.

Returns: the {@link Provider} of this instance.

initialize

public void initialize(int keysize)

Initializes this instance for the specified key size. Since no source of randomness is specified, a default one will be used.

Parameters: keysize the size of keys to use.

initialize

public void initialize(int keysize, SecureRandom random)

Initializes this instance for the specified key size and {@link SecureRandom}.

Parameters: keysize the size of keys to use. random the {@link SecureRandom} to use.

Since: 1.2

initialize

public void initialize(AlgorithmParameterSpec params)

Initializes this instance with the specified {@link AlgorithmParameterSpec}. Since no source of randomness is specified, a default one will be used.

Parameters: params the {@link AlgorithmParameterSpec} to use.

Throws: InvalidAlgorithmParameterException if the designated specifications are invalid.

Since: 1.2

initialize

public void initialize(AlgorithmParameterSpec params, SecureRandom random)

Initializes this instance with the specified {@link AlgorithmParameterSpec} and {@link SecureRandom}.

Parameters: params the {@link AlgorithmParameterSpec} to use. random the {@link SecureRandom} to use.

Throws: InvalidAlgorithmParameterException if the designated specifications are invalid.

Since: 1.2