@Override
  public Object set(final Object o, final short val) {
    ((ShortWritable) o).set(val);
    return o;
  }
The ParquetShortInspector can inspect both ShortWritables and IntWritables into shorts.
ql/src/java/org/apache/hadoop/hive/ql/io/parquet/serde/primitive/ParquetShortInspector.java