private void checkAccess(KeyAccess access) throws GeneralSecurityException {
    if (hasSecret() && !access.canAccessSecret()) {
      throw new GeneralSecurityException("No access");
    }
  }
Returns the {@link KeyTemplate} of the underlying {@link TinkKey}.

@throws UnsupportedOperationException if the underlying {@link TinkKey} has not implemented
    getKeyTemplate().
java_src/src/main/java/com/google/crypto/tink/tinkkey/KeyHandle.java