@Override
 protected void aggregate(FullHttpMessage aggregated, HttpContent content) throws Exception {
   if (content instanceof LastHttpContent) {
     // Merge trailing headers into the message.
     ((AggregatedFullHttpMessage) aggregated)
         .setTrailingHeaders(((LastHttpContent) content).trailingHeaders());
   }
 }
 @Override
 public FullHttpResponse touch() {
   super.touch();
   return this;
 }
 @Override
 public FullHttpResponse touch(Object hint) {
   super.touch(hint);
   return this;
 }
 @Override
 public FullHttpResponse retain() {
   super.retain();
   return this;
 }
 @Override
 public FullHttpResponse retain(int increment) {
   super.retain(increment);
   return this;
 }
 @Override
 public FullHttpResponse setProtocolVersion(HttpVersion version) {
   super.setProtocolVersion(version);
   return this;
 }
 @Override
 public FullHttpRequest touch() {
   super.touch();
   return this;
 }
 @Override
 public FullHttpRequest retain() {
   super.retain();
   return this;
 }