Netty事件傳播機制

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源碼

栗子

ch.pipeline().addLast(new InboundHandler1());  
ch.pipeline().addLast(new InboundHandler2()); 
ch.pipeline().addLast(new OutboundHandler1());  
ch.pipeline().addLast(new OutboundHandler2());

鏈表中的順序爲head->in1->in2->out1->out2->tail

輸出：

InboundHandler1 
InboundHandler2 
OutboundHandler2
OutboundHandler1

一次請求過來，先read，再write，根據順序

read : in1 in2
write: out2 out1

所以最後的順序就是 in1 in2 out 2 out1

拾遺

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由head開始的往下傳播的事件
fireChannelActive
fireChannelInactive
fireExceptionCaught
fireChannelRead
fireChannelReadComplete
…等等

由tail開始的往上傳播的事件
bind
connect
write
flush
…等等

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InboundHandler關心的事件：
MASK_EXCEPTION_CAUGHT
MASK_CHANNEL_REGISTERED
MASK_CHANNEL_ACTIVE
MASK_CHANNEL_READ
MASK_CHANNEL_READ_COMPLETE
…等等

OutboundHanlder關心的事件：
MASK_EXCEPTION_CAUGHT
MASK_BIND
MASK_CLOSE
MASK_READ
MASK_WRITE
MASK_FLUSH
…等等

參考：
https://blog.csdn.net/zhengchao1991/article/details/103583766
https://blog.csdn.net/qq_41737716/article/details/94734196
https://blog.csdn.net/zhengchao1991/article/details/103583766