docs: @Handler
      public void onRead(Input<ByteBuffer> event)
              throws InterruptedException {
          for (IOSubchannel channel : event.channels(IOSubchannel.class)) {
              ManagedBuffer<ByteBuffer> out = channel.byteBufferPool().acquire();
              out.backingBuffer().put(event.buffer().backingBuffer());
              channel.respond(Output.fromSink(out, event.isEndOfRecord()));
          }
      }