Channel concept & implementation— el Project (2)

DefaultChannelPipeline.java

public class DefaultChannelPipeline implements ChannelPipeline {

  private final Channel channel;
  private final HeadContext headContext;
  private final TailContext tailContext;

  public DefaultChannelPipeline(Channel channel) {
    this.channel = channel;
    this.tailContext = new TailContext(this);
    this.headContext = new HeadContext(this);

    this.tailContext.prev = this.headContext;
    this.headContext.next = this.tailContext;
  }
    
  @Override
  public ChannelPipeline addLast(ChannelHandler... handlers) {
    for (ChannelHandler handler : handlers) {
      this.addLast(handler);
    }
    return this;
  }

  private ChannelPipeline addLast(ChannelHandler handler) {
    final AbstractChannelHandlerContext prev = this.tailContext.prev;
    final AbstractChannelHandlerContext newHandlerContext =
        new DefaultChannelHandlerContext(name, this, eventLoop, handler);

    this.tailContext.prev = newHandlerContext;
    newHandlerContext.next = this.tailContext;

    prev.next = newHandlerContext;
    newHandlerContext.prev = prev;
    
    return this;
  }
  
  ...
}