@Override
  protected org.apache.thrift.protocol.TField getFieldDesc(_Fields setField) {
    switch (setField) {
      case PUT:
        return PUT_FIELD_DESC;
      case DELETE_SINGLE:
        return DELETE_SINGLE_FIELD_DESC;
      default:
        throw new java.lang.IllegalArgumentException("Unknown field id " + setField);
    }
  }
Find the _Fields constant that matches name, or null if its not found.
hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift2/generated/TMutation.java