ChannelPipeline
ChannelPipeline is a core component of Netty’s architecture. It represents an ordered list of ChannelHandler instances associated with a Channel. Each handler implements logic for processing inbound events (such as connection establishment, data reads, and exceptions) or outbound operations (such as writes and flushes). By chaining handlers together, the pipeline allows separation of concerns: decoding and encoding of data, application protocol handling, and business logic can be developed and reused independently.
Inbound and outbound events traverse the pipeline in opposite directions. When an inbound event occurs, it
The pipeline includes special head and tail handlers. The head connects the pipeline to the transport and
Handlers can be added, removed, or replaced at runtime using methods like addLast, remove, or replace, often
Common components placed in a ChannelPipeline include decoders, encoders, business-logic handlers, and idle-state or exception handlers.