Class PKCS8EncodedKeySpec

java.lang.Object

java.security.spec.EncodedKeySpec

java.security.spec.PKCS8EncodedKeySpec

All Implemented Interfaces:: DEREncodable^PREVIEW, KeySpec

public non-sealed class PKCS8EncodedKeySpec extends EncodedKeySpec implements DEREncodablePREVIEW

This class represents the ASN.1 encoding of a private key, encoded according to the ASN.1 type OneAsymmetricKey. The OneAsymmetricKey syntax is defined in the PKCS#8 standard as follows:

OneAsymmetricKey ::= SEQUENCE {
  version Version,
  privateKeyAlgorithm PrivateKeyAlgorithmIdentifier,
  privateKey PrivateKey,
  attributes       [0] Attributes OPTIONAL,
  ...,
  [[2: publicKey  [1] PublicKey OPTIONAL ]],
  ...
}

PrivateKeyInfo ::= OneAsymmetricKey

Version ::= INTEGER { v1(0), v2(1) }

PrivateKeyAlgorithmIdentifier ::= AlgorithmIdentifier

PrivateKey ::= OCTET STRING

PublicKey ::= BIT STRING

Attributes ::= SET OF Attribute

Since:

1.2

External Specifications

See Also:

Constructor Summary

Constructor	Description
`PKCS8EncodedKeySpec(byte[] encodedKey)`	Creates a new `PKCS8EncodedKeySpec` with the given encoded key.
`PKCS8EncodedKeySpec(byte[] encodedKey, String algorithm)`	Creates a new `PKCS8EncodedKeySpec` with the given encoded key and algorithm.

Method Summary

Modifier and Type	Method	Description
`byte[]`	`getEncoded()`	Returns the key bytes, encoded according to the PKCS #8 standard.
`final String`	`getFormat()`	Returns the name of the encoding format associated with this key specification.

Methods declared in class EncodedKeySpec

getAlgorithm

Methods declared in class Object

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

Constructor Details

PKCS8EncodedKeySpec

public PKCS8EncodedKeySpec(byte[] encodedKey)

Creates a new PKCS8EncodedKeySpec with the given encoded key.

Parameters:: encodedKey - the key, which is assumed to be encoded according to the PKCS #8 standard. The contents of the array are copied to protect against subsequent modification.
Throws:: NullPointerException - if encodedKey is null.

PKCS8EncodedKeySpec

public PKCS8EncodedKeySpec(byte[] encodedKey, String algorithm)

Creates a new PKCS8EncodedKeySpec with the given encoded key and algorithm. This constructor is useful when subsequent callers of the PKCS8EncodedKeySpec object might not know the algorithm of the private key.

Parameters:

encodedKey - the key, which is assumed to be encoded according to the PKCS #8 standard. The contents of the array are copied to protect against subsequent modification.

algorithm - the algorithm name of the encoded private key. See the AsymmetricKey Algorithms section in the Java Security Standard Algorithm Names Specification for information about standard asymmetric key algorithm names.

Throws:

NullPointerException - if encodedKey or algorithm is null.

IllegalArgumentException - if algorithm is the empty string ""

Since:

External Specifications

Method Details

getEncoded

public byte[] getEncoded()

Returns the key bytes, encoded according to the PKCS #8 standard.

Overrides:: getEncoded in class EncodedKeySpec
Returns:: the PKCS #8 encoding of the key. Returns a new array each time this method is called.

getFormat

public final String getFormat()

Returns the name of the encoding format associated with this key specification.

Specified by:: getFormat in class EncodedKeySpec
Returns:: the string "PKCS#8".

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https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/security/spec/PKCS8EncodedKeySpec.html