AlgorithmParameters (Java Platform SE 8 ) (original) (raw)

java.lang.Object
- java.security.AlgorithmParameters

public class AlgorithmParameters
extends Object
This class is used as an opaque representation of cryptographic parameters.
An AlgorithmParameters object for managing the parameters for a particular algorithm can be obtained by calling one of the getInstance factory methods (static methods that return instances of a given class).
Once an AlgorithmParameters object is obtained, it must be initialized via a call to init, using an appropriate parameter specification or parameter encoding.
A transparent parameter specification is obtained from anAlgorithmParameters object via a call togetParameterSpec, and a byte encoding of the parameters is obtained via a call to getEncoded.
Every implementation of the Java platform is required to support the following standard AlgorithmParameters algorithms:

AES
DES
DESede
DiffieHellman
DSA
These algorithms are described in the AlgorithmParameters section of the Java Cryptography Architecture Standard Algorithm Name Documentation. Consult the release documentation for your implementation to see if any other algorithms are supported.
Since:
1.2
See Also:
AlgorithmParameterSpec, DSAParameterSpec, KeyPairGenerator

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AlgorithmParameters(AlgorithmParametersSpi paramSpi,Provider provider,String algorithm)	Creates an AlgorithmParameters object.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods

Modifier and Type	Method	Description
String	getAlgorithm()	Returns the name of the algorithm associated with this parameter object.
byte[]	getEncoded()	Returns the parameters in their primary encoding format.
byte[]	getEncoded(String format)	Returns the parameters encoded in the specified scheme.
static AlgorithmParameters	getInstance(String algorithm)	Returns a parameter object for the specified algorithm.
static AlgorithmParameters	getInstance(String algorithm,Provider provider)	Returns a parameter object for the specified algorithm.
static AlgorithmParameters	getInstance(String algorithm,String provider)	Returns a parameter object for the specified algorithm.
<T extends AlgorithmParameterSpec>T	getParameterSpec(Class paramSpec)	Returns a (transparent) specification of this parameter object.
Provider	getProvider()	Returns the provider of this parameter object.
void	init(AlgorithmParameterSpec paramSpec)	Initializes this parameter object using the parameters specified in paramSpec.
void	init(byte[] params)	Imports the specified parameters and decodes them according to the primary decoding format for parameters.
void	init(byte[] params,String format)	Imports the parameters from params and decodes them according to the specified decoding scheme.
String	toString()	Returns a formatted string describing the parameters.

   * ### Methods inherited from class java.lang.[Object](../../java/lang/Object.html "class in java.lang")  
   `[clone](../../java/lang/Object.html#clone--), [equals](../../java/lang/Object.html#equals-java.lang.Object-), [finalize](../../java/lang/Object.html#finalize--), [getClass](../../java/lang/Object.html#getClass--), [hashCode](../../java/lang/Object.html#hashCode--), [notify](../../java/lang/Object.html#notify--), [notifyAll](../../java/lang/Object.html#notifyAll--), [wait](../../java/lang/Object.html#wait--), [wait](../../java/lang/Object.html#wait-long-), [wait](../../java/lang/Object.html#wait-long-int-)`

Constructor Detail

 * #### AlgorithmParameters  
 protected AlgorithmParameters([AlgorithmParametersSpi](../../java/security/AlgorithmParametersSpi.html "class in java.security") paramSpi,  
                               [Provider](../../java/security/Provider.html "class in java.security") provider,  
                               [String](../../java/lang/String.html "class in java.lang") algorithm)  
 Creates an AlgorithmParameters object.  
 Parameters:  
 `paramSpi` \- the delegate  
 `provider` \- the provider  
 `algorithm` \- the algorithm

Method Detail

* #### getAlgorithm  
public final [String](../../java/lang/String.html "class in java.lang") getAlgorithm()  
Returns the name of the algorithm associated with this parameter object.  
Returns:  
the algorithm name.  
* #### getInstance  
public static [AlgorithmParameters](../../java/security/AlgorithmParameters.html "class in java.security") getInstance([String](../../java/lang/String.html "class in java.lang") algorithm)  
                                       throws [NoSuchAlgorithmException](../../java/security/NoSuchAlgorithmException.html "class in java.security")  
Returns a parameter object for the specified algorithm.  
 This method traverses the list of registered security Providers, starting with the most preferred Provider. A new AlgorithmParameters object encapsulating the AlgorithmParametersSpi 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()](../../java/security/Security.html#getProviders--) method.  
 The returned parameter object must be initialized via a call to`init`, using an appropriate parameter specification or parameter encoding.  
Parameters:  
`algorithm` \- the name of the algorithm requested. See the AlgorithmParameters section in the [ Java Cryptography Architecture Standard Algorithm Name Documentation](../../../technotes/guides/security/StandardNames.html#AlgorithmParameters) for information about standard algorithm names.  
Returns:  
the new parameter object.  
Throws:  
`[NoSuchAlgorithmException](../../java/security/NoSuchAlgorithmException.html "class in java.security")` \- if no Provider supports an AlgorithmParametersSpi implementation for the specified algorithm.  
See Also:  
[Provider](../../java/security/Provider.html "class in java.security")  
* #### getInstance  
public static [AlgorithmParameters](../../java/security/AlgorithmParameters.html "class in java.security") getInstance([String](../../java/lang/String.html "class in java.lang") algorithm,  
                                              [String](../../java/lang/String.html "class in java.lang") provider)  
                                       throws [NoSuchAlgorithmException](../../java/security/NoSuchAlgorithmException.html "class in java.security"),  
                                              [NoSuchProviderException](../../java/security/NoSuchProviderException.html "class in java.security")  
Returns a parameter object for the specified algorithm.  
 A new AlgorithmParameters object encapsulating the AlgorithmParametersSpi 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()](../../java/security/Security.html#getProviders--) method.  
The returned parameter object must be initialized via a call to`init`, using an appropriate parameter specification or parameter encoding.  
Parameters:  
`algorithm` \- the name of the algorithm requested. See the AlgorithmParameters section in the [ Java Cryptography Architecture Standard Algorithm Name Documentation](../../../technotes/guides/security/StandardNames.html#AlgorithmParameters) for information about standard algorithm names.  
`provider` \- the name of the provider.  
Returns:  
the new parameter object.  
Throws:  
`[NoSuchAlgorithmException](../../java/security/NoSuchAlgorithmException.html "class in java.security")` \- if an AlgorithmParametersSpi implementation for the specified algorithm is not available from the specified provider.  
`[NoSuchProviderException](../../java/security/NoSuchProviderException.html "class in java.security")` \- if the specified provider is not registered in the security provider list.  
`[IllegalArgumentException](../../java/lang/IllegalArgumentException.html "class in java.lang")` \- if the provider name is null or empty.  
See Also:  
[Provider](../../java/security/Provider.html "class in java.security")  
* #### getInstance  
public static [AlgorithmParameters](../../java/security/AlgorithmParameters.html "class in java.security") getInstance([String](../../java/lang/String.html "class in java.lang") algorithm,  
                                              [Provider](../../java/security/Provider.html "class in java.security") provider)  
                                       throws [NoSuchAlgorithmException](../../java/security/NoSuchAlgorithmException.html "class in java.security")  
Returns a parameter object for the specified algorithm.  
 A new AlgorithmParameters object encapsulating the AlgorithmParametersSpi implementation from the specified Provider object is returned. Note that the specified Provider object does not have to be registered in the provider list.  
The returned parameter object must be initialized via a call to`init`, using an appropriate parameter specification or parameter encoding.  
Parameters:  
`algorithm` \- the name of the algorithm requested. See the AlgorithmParameters section in the [ Java Cryptography Architecture Standard Algorithm Name Documentation](../../../technotes/guides/security/StandardNames.html#AlgorithmParameters) for information about standard algorithm names.  
`provider` \- the name of the provider.  
Returns:  
the new parameter object.  
Throws:  
`[NoSuchAlgorithmException](../../java/security/NoSuchAlgorithmException.html "class in java.security")` \- if an AlgorithmParameterGeneratorSpi implementation for the specified algorithm is not available from the specified Provider object.  
`[IllegalArgumentException](../../java/lang/IllegalArgumentException.html "class in java.lang")` \- if the provider is null.  
Since:  
1.4  
See Also:  
[Provider](../../java/security/Provider.html "class in java.security")  
* #### getProvider  
public final [Provider](../../java/security/Provider.html "class in java.security") getProvider()  
Returns the provider of this parameter object.  
Returns:  
the provider of this parameter object  
* #### init  
public final void init([AlgorithmParameterSpec](../../java/security/spec/AlgorithmParameterSpec.html "interface in java.security.spec") paramSpec)  
                throws [InvalidParameterSpecException](../../java/security/spec/InvalidParameterSpecException.html "class in java.security.spec")  
Initializes this parameter object using the parameters specified in `paramSpec`.  
Parameters:  
`paramSpec` \- the parameter specification.  
Throws:  
`[InvalidParameterSpecException](../../java/security/spec/InvalidParameterSpecException.html "class in java.security.spec")` \- if the given parameter specification is inappropriate for the initialization of this parameter object, or if this parameter object has already been initialized.  
* #### init  
public final void init(byte[] params)  
                throws [IOException](../../java/io/IOException.html "class in java.io")  
Imports the specified parameters and decodes them according to the primary decoding format for parameters. The primary decoding format for parameters is ASN.1, if an ASN.1 specification for this type of parameters exists.  
Parameters:  
`params` \- the encoded parameters.  
Throws:  
`[IOException](../../java/io/IOException.html "class in java.io")` \- on decoding errors, or if this parameter object has already been initialized.  
* #### init  
public final void init(byte[] params,  
                       [String](../../java/lang/String.html "class in java.lang") format)  
                throws [IOException](../../java/io/IOException.html "class in java.io")  
Imports the parameters from `params` and decodes them according to the specified decoding scheme. If `format` is null, the primary decoding format for parameters is used. The primary decoding format is ASN.1, if an ASN.1 specification for these parameters exists.  
Parameters:  
`params` \- the encoded parameters.  
`format` \- the name of the decoding scheme.  
Throws:  
`[IOException](../../java/io/IOException.html "class in java.io")` \- on decoding errors, or if this parameter object has already been initialized.  
* #### getParameterSpec  
public final <T extends [AlgorithmParameterSpec](../../java/security/spec/AlgorithmParameterSpec.html "interface in java.security.spec")> T getParameterSpec([Class](../../java/lang/Class.html "class in java.lang")<T> paramSpec)  
                                                            throws [InvalidParameterSpecException](../../java/security/spec/InvalidParameterSpecException.html "class in java.security.spec")  
Returns a (transparent) specification of this parameter object.`paramSpec` identifies the specification class in which the parameters should be returned. It could, for example, be`DSAParameterSpec.class`, to indicate that the parameters should be returned in an instance of the`DSAParameterSpec` class.  
Type Parameters:  
`T` \- the type of the parameter specification to be returrned  
Parameters:  
`paramSpec` \- the specification class in which the parameters should be returned.  
Returns:  
the parameter specification.  
Throws:  
`[InvalidParameterSpecException](../../java/security/spec/InvalidParameterSpecException.html "class in java.security.spec")` \- if the requested parameter specification is inappropriate for this parameter object, or if this parameter object has not been initialized.  
* #### getEncoded  
public final byte[] getEncoded()  
                        throws [IOException](../../java/io/IOException.html "class in java.io")  
Returns the parameters in their primary encoding format. The primary encoding format for parameters is ASN.1, if an ASN.1 specification for this type of parameters exists.  
Returns:  
the parameters encoded using their primary encoding format.  
Throws:  
`[IOException](../../java/io/IOException.html "class in java.io")` \- on encoding errors, or if this parameter object has not been initialized.  
* #### getEncoded  
public final byte[] getEncoded([String](../../java/lang/String.html "class in java.lang") format)  
                        throws [IOException](../../java/io/IOException.html "class in java.io")  
Returns the parameters encoded in the specified scheme. If `format` is null, the primary encoding format for parameters is used. The primary encoding format is ASN.1, if an ASN.1 specification for these parameters exists.  
Parameters:  
`format` \- the name of the encoding format.  
Returns:  
the parameters encoded using the specified encoding scheme.  
Throws:  
`[IOException](../../java/io/IOException.html "class in java.io")` \- on encoding errors, or if this parameter object has not been initialized.  
* #### toString  
public final [String](../../java/lang/String.html "class in java.lang") toString()  
Returns a formatted string describing the parameters.  
Overrides:  
`[toString](../../java/lang/Object.html#toString--)` in class `[Object](../../java/lang/Object.html "class in java.lang")`  
Returns:  
a formatted string describing the parameters, or null if this parameter object has not been initialized.

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AlgorithmParameters (Java Platform SE 8 ) (original) (raw)

Constructor Summary

Method Summary

Constructor Detail

Method Detail