Class EdDSAParameterSpec

java.lang.Object

java.security.spec.EdDSAParameterSpec

All Implemented Interfaces:: AlgorithmParameterSpec

public class EdDSAParameterSpec extends Object implements AlgorithmParameterSpec

A class used to specify EdDSA signature and verification parameters. All algorithm modes in RFC 8032: Edwards-Curve Digital Signature Algorithm (EdDSA) can be specified using combinations of the settings in this class.

If prehash is true, then the mode is Ed25519ph or Ed448ph
Otherwise, if a context is present, the mode is Ed25519ctx or Ed448
Otherwise, the mode is Ed25519 or Ed448

Since:

External Specifications

Constructor Summary

Constructor	Description
`EdDSAParameterSpec(boolean prehash)`	Construct an `EdDSAParameterSpec` by specifying whether the prehash mode is used.
`EdDSAParameterSpec(boolean prehash, byte[] context)`	Construct an `EdDSAParameterSpec` by specifying a context and whether the prehash mode is used.

Method Summary

Modifier and Type	Method	Description
`Optional<byte[]>`	`getContext()`	Get the context that the signature will use.
`boolean`	`isPrehash()`	Get whether the prehash mode is specified.

Methods declared in class Object

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

Constructor Details

EdDSAParameterSpec

public EdDSAParameterSpec(boolean prehash)

Construct an EdDSAParameterSpec by specifying whether the prehash mode is used. No context is provided so this constructor specifies a mode in which the context is null. Note that this mode may be different from the mode in which an empty array is used as the context.

Parameters:: prehash - whether the prehash mode is specified.

EdDSAParameterSpec

public EdDSAParameterSpec(boolean prehash, byte[] context)

Construct an EdDSAParameterSpec by specifying a context and whether the prehash mode is used. The context may not be null, but it may be an empty array. The mode used when the context is an empty array may not be the same as the mode used when the context is absent.

Parameters:: prehash - whether the prehash mode is specified.; context - the context is copied and bound to the signature.
Throws:: NullPointerException - if context is null.; InvalidParameterException - if context length is greater than 255.

Method Details

isPrehash

public boolean isPrehash()

Get whether the prehash mode is specified.

Returns:: whether the prehash mode is specified.

getContext

public Optional<byte[]> getContext()

Get the context that the signature will use.

Returns:: Optional contains a copy of the context or empty if context is null.

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https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/security/spec/EdDSAParameterSpec.html