VerifiableCredentials

This provides a basic implementation of the W3C Verifiable Credential specification which was approved as a recommendation in late June 2022 Specification can be found on https://www.w3.org/TR/vc-data-model/

Please refer to Main.java class for sample usage

CredentialSubject credentialSubject = new CredentialSubject();
credentialSubject.addClaim("name", "Thusitha Dayaratne");
credentialSubject.addClaim("job", "Research Fellow");
credentialSubject.addClaim("university", "Monash University");
credentialSubject.addClaim("id", "0123456789");

Credential credential = new Credential.Builder()
        .credentialSubject(credentialSubject)
        .build();
var dateTime = LocalDateTime.now();
CredentialMetaData credentialMetaData = new CredentialMetaData.Builder()
        .id("vc12345")
        .issuer("MonashUniversity")
        .additionalType("MonashCredential")
        .issuanceDate(dateTime)
        .expirationDate(dateTime.plusYears(1))
        .build();

KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("Ed25519");
byte[] keyBytesForSender = Mnemonic.toKey("sponsor ride say achieve senior height crumble promote " +
        "universe write dove bomb faculty side human taste paper grocery robot grab reason fork soul above " +
        "sphere");
keyPairGenerator.initialize(256, new FixedSecureRandom(keyBytesForSender));
KeyPair keyPair = keyPairGenerator.generateKeyPair();
Proof proof = new Ed25519Signature2020(dateTime, credential, credentialMetaData, URI.create("linkToPublicKey"),
        "assertion", keyPair.getPrivate());

VerifiableCredential verifiableCredential = new VerifiableCredential.Builder()
        .credential(credential)
        .metadata(credentialMetaData)
        .proof(proof)
        .build();
JsonObject jsonRepresentation = VCUtil.getJsonRepresentation(verifiableCredential);
System.out.println(jsonRepresentation);