@Override
  public byte[] toByteArray() {
    FilterProtos.RowFilter.Builder builder = FilterProtos.RowFilter.newBuilder();
    builder.setCompareFilter(super.convert());
    return builder.build().toByteArray();
  }
Returns The filter serialized using pb
hbase-client/src/main/java/org/apache/hadoop/hbase/filter/RowFilter.java