code: public synchronized PacketBuilder withLong(final long l)
      {
          checkBuilt();
          try
          {
              dataOutputStream.writeLong(l);
          }
          catch (final IOException e)
          {
              logger.error("Unable to add long: {} : {}", e.getClass(), e.getMessage());
          }
          return this;
      }
docs: Adds a long
  @param l Long
  @throws IllegalStateException see {@link #checkBuilt()}