Netty分布式server启动流程Nio创建源码分析

//创建boss和worker线程(1)

EventLoopGroup bossGroup = new NioEventLoopGroup( 1 );

EventLoopGroup workerGroup = new NioEventLoopGroup();

//创建ServerBootstrap(2)

ServerBootstrap b = new ServerBootstrap();

//初始化boss和work线程化两个线程(3)

b.group(bossGroup, workerGroup)

         //声明NioServerSocketChannel(4)

         .channel(NioServerSocketChannel. class )

         //初始化客户端Handler(5)

         .childHandler( new ChannelInitializer<SocketChannel>() {

             @Override

             public void initChannel(SocketChannel ch) {

                 ch.pipeline().addLast( new StringDecoder());

                 ch.pipeline().addLast( new StringEncoder());

                 ch.pipeline().addLast( new ServerHandler());

             }

         });

//绑定端口(6)

ChannelFuture f = b.bind( 8888 ).sync();

f.channel().closeFuture().sync();

ChannelFuture f = b.bind( 8888 ).sync();

public ChannelFuture bind( int inetPort) {

     return bind( new InetSocketAddress(inetPort));

}

public ChannelFuture bind(SocketAddress localAddress) {

     validate();

     return doBind(localAddress);

}

private ChannelFuture doBind( final SocketAddress localAddress) {

     //初始化并注册(1)

     final ChannelFuture regFuture = initAndRegister();

     //获得channel(2)

     final Channel channel = regFuture.channel();

     if (regFuture.cause() != null ) {

         return regFuture;

     }

     if (regFuture.isDone()) {

         ChannelPromise promise = channel.newPromise();

         //绑定(3)

         doBind0(regFuture, channel, localAddress, promise);

         return promise;

     } else {

         //去除非关键代码

         return promise;

     }

}

final ChannelFuture regFuture = initAndRegister();

final ChannelFuture initAndRegister() {

     Channel channel = null ;

     try {

         //创建channel

         channel = channelFactory.newChannel();

         init(channel);

     } catch (Throwable t) {

         //忽略非关键代码

     }

     ChannelFuture regFuture = config().group().register(channel);

     //忽略非关键代码

     return regFuture;

}

channel = channelFactory.newChannel();

public B channelFactory(ChannelFactory<? extends C> channelFactory) {

     this .channelFactory = channelFactory;

     return (B) this ;

}

public B channel(Class&lt;? extends C&gt; channelClass) {

     return channelFactory(new ReflectiveChannelFactory&lt;C&gt;(channelClass));

}

@Override

public T newChannel() {

     try {

         return clazz.newInstance();

     } catch (Throwable t) {

         throw new ChannelException( "Unable to create Channel from class " + clazz, t);

     }

}

public NioServerSocketChannel() {

     this (newSocket(DEFAULT_SELECTOR_PROVIDER));

}

private static final SelectorProvider DEFAULT_SELECTOR_PROVIDER = SelectorProvider.provider();

private static ServerSocketChannel newSocket(SelectorProvider provider) {

     return provider.openServerSocketChannel();

}

public NioServerSocketChannel(ServerSocketChannel channel) {

     super ( null , channel, SelectionKey.OP_ACCEPT);

     config = new NioServerSocketChannelConfig( this , javaChannel().socket());

}

protected AbstractNioMessageChannel(Channel parent, SelectableChannel ch, int readInterestOp) {

     super (parent, ch, readInterestOp);

}

protected AbstractNioChannel(Channel parent, SelectableChannel ch, int readInterestOp) {

     super (parent);

     //保存channel

     this .ch = ch;

     //绑定事件

     this .readInterestOp = readInterestOp;

     try {

         //设置为非阻塞

         ch.configureBlocking( false );

     } catch (IOException e) {

         //去掉非关键代码

     }

}

this .ch = ch;

ch.configureBlocking( false );

protected AbstractChannel(Channel parent) {

     this .parent = parent;

     id = newId();

     unsafe = newUnsafe();

     pipeline = newChannelPipeline();

}

unsafe = newUnsafe();

pipeline = newChannelPipeline();