@Override
  public final String getTokenKind() {
    // All HBase authentication tokens are "HBASE_AUTH_TOKEN"'s. We differentiate between them
    // via the code().
    return AUTH_TOKEN_TYPE;
  }
Base implementation of {@link SaslClientAuthenticationProvider}. All implementations should
extend this class instead of directly implementing the interface.
hbase-client/src/main/java/org/apache/hadoop/hbase/security/provider/AbstractSaslClientAuthenticationProvider.java