private boolean isValidValue(Object fieldValue, DataWriter writer) {
      if (writer instanceof TimestampDataWriter) {
        return ((TimestampDataWriter) writer).isValidTimestamp(fieldValue);
      }
      return true;
    }
Checks that an inspector matches the category indicated as a parameter.
@param inspector The object inspector to check
@param category The category to match
@throws IllegalArgumentException if inspector does not match the category
ql/src/java/org/apache/hadoop/hive/ql/io/parquet/write/DataWritableWriter.java