Question for intercepting the request and directly writing back in IoFilter

[jian wu]

Hi,

I took a quick look in SSLFilter.java and wrote a simple
program. It seems that in the IoFilter.messageReceived()
method, we can simply intercept request and write back
the response by doing:
==========================================
public void messageReceived(
 NextFilter nextFilter, IoSession session, Object message) {
 // ... ...
 WriteFuture writeFuture = new WriteFuture();
 nextFilter.filterWrite( session,
  new WriteRequest( heartbeatResponse, writeFuture ) );
}
==========================================

Is this a good practice? If Yes, I assume that the nextFilter
passed in actually is bi-directional, on reading side upward
and on writing side downward

Thanks a lot for your help!

Jian