IMultithreadedChannel is a multithreaded version of the IChannel API. Each IChannel-like method is accomanied by a String key representing which virtual "instance" of the channel is being called. This allows a single instance of IMultithreadedChannel to take the place of many IChannel instances.
A problem with IMultithreadedChannel since 2002 is that it is not well understood under what circumstances and why it is appropriate to write an IMultithreadedChannel rather than a basic IChannel. This is something that should be addressed in the JavaDoc for this interface. However, this Wiki page is also a place to collect insight and experience with this API.
IChannel vs. IMultithreadedChannel
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