@Override
  public Object getNegotiatedProperty(String propName) {
    throwIfNotComplete();
    return Sasl.QOP.equals(propName) ? "auth" : null;
  }
This class was copied from Hadoop Common (3.1.2) and subsequently modified.
hbase-examples/src/main/java/org/apache/hadoop/hbase/security/provider/example/SaslPlainServer.java