@org.apache.thrift.annotation.Nullable
    public static _Fields findByThriftId(int fieldId) {
      switch(fieldId) {
        case 1: // BOOL_VAL
          return BOOL_VAL;
        case 2: // BYTE_VAL
          return BYTE_VAL;
        case 3: // I16_VAL
          return I16_VAL;
        case 4: // I32_VAL
          return I32_VAL;
        case 5: // I64_VAL
          return I64_VAL;
        case 6: // DOUBLE_VAL
          return DOUBLE_VAL;
        case 7: // STRING_VAL
          return STRING_VAL;
        default:
          return null;
      }
    }
Find the _Fields constant that matches fieldId, or null if its not found.
service-rpc/src/gen/thrift/gen-javabean/org/apache/hive/service/rpc/thrift/TColumnValue.java