public boolean isSet(_Fields field) {
    if (field == null) {
      throw new java.lang.IllegalArgumentException();
    }

    switch (field) {
    case MY_BOOL:
      return isSetMy_bool();
    case MY_BYTE:
      return isSetMy_byte();
    case MY_16BIT_INT:
      return isSetMy_16bit_int();
    case MY_32BIT_INT:
      return isSetMy_32bit_int();
    case MY_64BIT_INT:
      return isSetMy_64bit_int();
    case MY_DOUBLE:
      return isSetMy_double();
    case MY_STRING:
      return isSetMy_string();
    case MY_BINARY:
      return isSetMy_binary();
    case MY_STRING_STRING_MAP:
      return isSetMy_string_string_map();
    case MY_STRING_ENUM_MAP:
      return isSetMy_string_enum_map();
    case MY_ENUM_STRING_MAP:
      return isSetMy_enum_string_map();
    case MY_ENUM_STRUCT_MAP:
      return isSetMy_enum_struct_map();
    case MY_ENUM_STRINGLIST_MAP:
      return isSetMy_enum_stringlist_map();
    case MY_ENUM_STRUCTLIST_MAP:
      return isSetMy_enum_structlist_map();
    case MY_STRINGLIST:
      return isSetMy_stringlist();
    case MY_STRUCTLIST:
      return isSetMy_structlist();
    case MY_ENUMLIST:
      return isSetMy_enumlist();
    case MY_STRINGSET:
      return isSetMy_stringset();
    case MY_ENUMSET:
      return isSetMy_enumset();
    case MY_STRUCTSET:
      return isSetMy_structset();
    }
    throw new java.lang.IllegalStateException();
  }
Returns true if field corresponding to fieldID is set (has been assigned a value) and false otherwise
serde/src/gen/thrift/gen-javabean/org/apache/hadoop/hive/serde2/thrift/test/MegaStruct.java