code: @Override
      public void doSerialize( JsonWriter writer, T[][] values, JsonSerializationContext ctx, JsonSerializerParameters params ) {
          if ( !ctx.isWriteEmptyJsonArrays() && values.length == 0 ) {
              writer.cancelName();
              return;
          }
  
          writer.beginArray();
          for ( T[] array : values ) {
              writer.beginArray();
              for ( T value : array ) {
                  serializer.serialize( writer, value, ctx, params );
              }
              writer.endArray();
          }
          writer.endArray();
      }
docs: {@inheritDoc}