@Override
  @AccessesPartialKey
  public Key deriveKey(byte[] salt) throws GeneralSecurityException {
    InputStream inputStream = prf.computePrf(salt);
    return MutableKeyDerivationRegistry.globalInstance()
        .createKeyFromRandomness(
            key.getParameters().getDerivedKeyParameters(),
            inputStream,
            key.getIdRequirementOrNull(),
            InsecureSecretKeyAccess.get());
  }
Implements the KeyDeriver interface by first applying a Prf and then using the global registry to
create the correct key.
java_src/src/main/java/com/google/crypto/tink/keyderivation/internal/PrfBasedKeyDeriver.java