public class AlgorithmParameterGenerator extends Object
AlgorithmParameterGenerator
is used to generate algorithm
parameters for specified algorithms.
In case the client does not explicitly initialize the
AlgorithmParameterGenerator
(via a call to an
init()
method), each provider must supply (and document) a
default initialization. For example, the GNU provider uses a default
modulus prime size of 1024
bits for the generation of DSA
parameters.
AlgorithmParameters
,
AlgorithmParameterSpec
Modifier | Constructor and Description |
---|---|
protected |
AlgorithmParameterGenerator(AlgorithmParameterGeneratorSpi paramGenSpi,
Provider provider,
String algorithm)
Constructs a new instance of
AlgorithmParameterGenerator . |
Modifier and Type | Method and Description |
---|---|
AlgorithmParameters |
generateParameters() |
String |
getAlgorithm() |
static AlgorithmParameterGenerator |
getInstance(String algorithm)
Returns a new
AlgorithmParameterGenerator instance which
generates algorithm parameters for the specified algorithm. |
static AlgorithmParameterGenerator |
getInstance(String algorithm,
Provider provider)
Returns a new
AlgorithmParameterGenerator instance which
generates algorithm parameters for the specified algorithm. |
static AlgorithmParameterGenerator |
getInstance(String algorithm,
String provider)
Returns a new
AlgorithmParameterGenerator instance which
generates algorithm parameters for the specified algorithm. |
Provider |
getProvider() |
void |
init(AlgorithmParameterSpec genParamSpec)
Initializes this instance with the specified
AlgorithmParameterSpec . |
void |
init(AlgorithmParameterSpec genParamSpec,
SecureRandom random)
Initializes this instance with the specified
AlgorithmParameterSpec
and source of randomness. |
void |
init(int size)
Initializes this instance with the specified size.
|
void |
init(int size,
SecureRandom random)
Initializes this instance with the specified key-size and source of
randomness.
|
protected AlgorithmParameterGenerator(AlgorithmParameterGeneratorSpi paramGenSpi, Provider provider, String algorithm)
AlgorithmParameterGenerator
.paramGenSpi
- the generator to use.provider
- the provider to use.algorithm
- the algorithm to use.public final String getAlgorithm()
public static AlgorithmParameterGenerator getInstance(String algorithm) throws NoSuchAlgorithmException
AlgorithmParameterGenerator
instance which
generates algorithm parameters for the specified algorithm.algorithm
- the name of algorithm to use.NoSuchAlgorithmException
- if algorithm
is not
implemented by any provider.IllegalArgumentException
- if algorithm
is
null
or is an empty string.public static AlgorithmParameterGenerator getInstance(String algorithm, String provider) throws NoSuchAlgorithmException, NoSuchProviderException
AlgorithmParameterGenerator
instance which
generates algorithm parameters for the specified algorithm.algorithm
- the name of algorithm to use.provider
- the name of the Provider
to use.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.public static AlgorithmParameterGenerator getInstance(String algorithm, Provider provider) throws NoSuchAlgorithmException
AlgorithmParameterGenerator
instance which
generates algorithm parameters for the specified algorithm.algorithm
- the name of algorithm to use.provider
- the Provider
to use.NoSuchAlgorithmException
- if the algorithm is not implemented by
Provider
.IllegalArgumentException
- if either algorithm
or
provider
is null
, or if
algorithm
is an empty string.Provider
public final Provider getProvider()
Provider
of this generator.public final void init(int size)
size
- size (in bits) to use.public final void init(int size, SecureRandom random)
size
- the size (in bits) to use.random
- the SecureRandom
to use.public final void init(AlgorithmParameterSpec genParamSpec) throws InvalidAlgorithmParameterException
AlgorithmParameterSpec
.
Since no source of randomness is supplied, a default one will be used.genParamSpec
- the AlgorithmParameterSpec
to use.InvalidAlgorithmParameterException
- if genParamSpec
is invalid.public final void init(AlgorithmParameterSpec genParamSpec, SecureRandom random) throws InvalidAlgorithmParameterException
AlgorithmParameterSpec
and source of randomness.genParamSpec
- the AlgorithmParameterSpec
to use.random
- the SecureRandom
to use.InvalidAlgorithmParameterException
- if genParamSpec
is invalid.public final AlgorithmParameters generateParameters()
AlgorithmParameters
.