@org.apache.thrift.annotation.Nullable
    public static _Fields findByThriftId(int fieldId) {
      switch(fieldId) {
        case 1: // S_INT_STRING
          return S_INT_STRING;
        case 2: // A_STRING
          return A_STRING;
        default:
          return null;
      }
    }
Find the _Fields constant that matches fieldId, or null if its not found.
serde/src/gen/thrift/gen-javabean/org/apache/hadoop/hive/serde2/thrift/test/SetIntString.java