/** @return The filter serialized using pb */ public byte[] toByteArray() { FilterProtos.MultipleColumnPrefixFilter.Builder builder = FilterProtos.MultipleColumnPrefixFilter.newBuilder(); for (byte[] element : sortedPrefixes) { if (element != null) builder.addSortedPrefixes(ByteStringer.wrap(element)); } return builder.build().toByteArray(); }