- DefaultChannelPipeline detects such cases and creates an object called
'bridge' that works as a man-in-the-middle to deal with a race
condition
- Slight performance drop is observed but still faster than v3.
Couldn't find much from a profiler yet.
- Previously, head was a volatile field which is null at the beginning.
While iterating over the pipeline, if the loop hits null, it called
Channel.Unsafe explicitly.
- Instead, I created an outbound handler that redirects all requests
to the unsafe and made it a final field of the pipeline.
- As a result, DefaultChannelPipeline code became much simpler.
- Add EventExecutor and make EventLoop extend it
- Add SingleThreadEventExecutor and MultithreadEventExecutor
- Add EventExecutor's default implementation
- Fixed an API design problem where there is no way to get non-bypass
buffer of desired type
