docs: @Override
      public void readFields(DataInput in) throws IOException {
          try {
              values.clear();
              int entries = in.readInt();
              for (int i = 0; i < entries; i++) {
                  ValueWritable vw = new ValueWritable();
                  vw.readFields(in);
                  values.add(vw);
              }
          } catch (Exception e) {
              e.printStackTrace();
              throw new RuntimeException(e);
          }
      }