Class KemReceiver

java.lang.Object

net.jrodolfo.java_evolution.java21.key_encapsulation.KemReceiver

public class KemReceiver
extends Object

Represents the receiver side of a Java 21 KEM exchange.

The receiver owns the asymmetric key pair. It shares the public key with the sender and keeps the private key secret. The private key is later used to decapsulate the sender's encapsulation message.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	KEM_ALGORITHM	The Java 21 KEM algorithm name used by the standard API.
static final String	KEY_PAIR_ALGORITHM	The key agreement key type used by this compact example.

Method Summary

Modifier and Type	Method	Description
static KemReceiver	create()	Creates a receiver with a fresh X25519 key pair.
SecretKey	decapsulate(byte[] encapsulation)	Recovers the shared secret from the sender's encapsulation message.
PublicKey	publicKey()	Returns the public key that can be shared with the sender.

Methods inherited from class Object

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

Field Details

KEY_PAIR_ALGORITHM

public static final String KEY_PAIR_ALGORITHM

The key agreement key type used by this compact example.

See Also:

• Constant Field Values

KEM_ALGORITHM

public static final String KEM_ALGORITHM

The Java 21 KEM algorithm name used by the standard API.

See Also:

• Constant Field Values

Method Details

create

public static KemReceiver create()
                          throws NoSuchAlgorithmException

Creates a receiver with a fresh X25519 key pair.

Returns:

a receiver ready to publish its public key

Throws:

NoSuchAlgorithmException - if X25519 is not available from the active providers

publicKey

public PublicKey publicKey()

Returns the public key that can be shared with the sender.

Returns:

the receiver public key

decapsulate

public SecretKey decapsulate(byte[] encapsulation)
                      throws NoSuchAlgorithmException,
InvalidKeyException,
DecapsulateException

Recovers the shared secret from the sender's encapsulation message.

Parameters:

encapsulation - the byte message produced by the sender

Returns:

the receiver-side shared secret

Throws:

NoSuchAlgorithmException - if DHKEM is not available from the active providers

InvalidKeyException - if the receiver private key cannot be used for DHKEM

DecapsulateException - if the encapsulation message cannot be decapsulated