public Object getFieldValue(_Fields field) {
    switch (field) {
    case NAME:
      return getName();

    case CONFIGURATION:
      return getConfiguration();

    }
    throw new IllegalStateException();
  }
Returns true if field configuration is set (has been assigned a value) and false otherwise
hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift2/generated/NamespaceDescriptor.java