public static GenericUDTF cloneGenericUDTF(GenericUDTF genericUDTF) {
    if (null == genericUDTF) {
      return null;
    }
    return ReflectionUtils.newInstance(genericUDTF.getClass(), null);
  }
Create a copy of an existing GenericUDTF.
ql/src/java/org/apache/hadoop/hive/ql/exec/FunctionRegistry.java