Channel Class Hierarchy

1. Channel Class Hierarchy

1.1. Channel

Used for network I/O.

 * A nexus to a network socket or a component which is capable of I/O
 * operations such as read, write, connect, and bind.
 public interface Channel extends AttributeMap, ChannelOutboundInvoker, Comparable<Channel> {

1.2. AbstractChannel

A skeletal implementation of Channel.

/**
 * A skeletal {@link Channel} implementation.
 */
private final Channel parent;
private final ChannelId id;
private final Unsafe unsafe;
private final DefaultChannelPipeline pipeline;

private final CloseFuture closeFuture = new CloseFuture(this);

private volatile SocketAddress localAddress;
private volatile SocketAddress remoteAddress;
private volatile EventLoop eventLoop;

1.3. AbstractNioChannel

A Channel implemented using a Selector.

/**
 * Abstract base class for {@link Channel} implementations which use a Selector based approach.
 */
public abstract class AbstractNioChannel extends AbstractChannel {

1.4. AbstractNioByteChannel

A client-side channel that operates on byte streams and is interested in READ events.

/**
 * {@link AbstractNioChannel} base class for {@link Channel}s that operate on bytes.
 */
public abstract class AbstractNioByteChannel extends AbstractNioChannel {
    protected AbstractNioByteChannel(Channel parent, SelectableChannel ch) {
        super(parent, ch, SelectionKey.OP_READ);

    }
}

1.5. AbstractNioMessageChannel

A server-side channel interested in accept events.

/**
 * A {@link io.netty.channel.socket.ServerSocketChannel} implementation which uses
 * NIO selector based implementation to accept new connections.
 */
public class NioServerSocketChannel extends AbstractNioMessageChannel
                             implements io.netty.channel.socket.ServerSocketChannel {
    public NioServerSocketChannel(ServerSocketChannel channel) {
        super(null, channel, SelectionKey.OP_ACCEPT);
        config = new NioServerSocketChannelConfig(this, javaChannel().socket());
    }
}

2. Config Class Hierarchy