（1）启动类
package test;
import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
/**
* netty服务器启动类
* @author songyan
*
*/
public class HttpProxyServer {
public static void main(String[] args) throws Exception {
int LOCAL_PORT = (args.length > 0) ? Integer.parseInt(args[0]) : 5688;// 代理的端口号
System.out.println("Proxying on port " + LOCAL_PORT);
// 主从线程组模型
EventLoopGroup bossGroup = new NioEventLoopGroup(1);
EventLoopGroup workerGroup = new NioEventLoopGroup();
try {
// 创建核心类
ServerBootstrap b = new ServerBootstrap();
b.group(bossGroup, workerGroup).channel(NioServerSocketChannel.class)
// 添加助手类
.childHandler(new ServerInitialzer()).bind(LOCAL_PORT).sync().channel().closeFuture().sync();
} finally {
// 关闭主从线程
bossGroup.shutdownGracefully();
workerGroup.shutdownGracefully();
}
}
}
（2）初始化类
package test;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.socket.SocketChannel;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.HttpServerCodec;
import io.netty.handler.codec.http.websocketx.WebSocketServerProtocolHandler;
import io.netty.handler.stream.ChunkedWriteHandler;
/**
*
* @author songyan
* 通用的初始化类
*/
public class ServerInitialzer extends ChannelInitializer<SocketChannel> {
@Override
protected void initChannel(SocketChannel ch) throws Exception {
ChannelPipeline pipeline = ch.pipeline();
//netty是基于http的，所以要添加http编码器
pipeline.addLast(new HttpServerCodec());
//对写大数据流的支持
pipeline.addLast(new ChunkedWriteHandler());
//设置单次请求的文件大小上限
pipeline.addLast(new HttpObjectAggregator(1024*1024*10));
//websocket 服务器处理的协议，用于指定给客户端连接访问的路由 : /ws
pipeline.addLast(new WebSocketServerProtocolHandler("/ws"));
//自定义的路由
pipeline.addLast(new HttpHandler());
}
}
（3）自定义路由
package test;
import java.time.LocalDateTime;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import io.netty.bootstrap.Bootstrap;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.channel.group.ChannelGroup;
import io.netty.channel.group.DefaultChannelGroup;
import io.netty.handler.codec.http.FullHttpRequest;
import io.netty.handler.codec.http.HttpMethod;
import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
import io.netty.handler.codec.http.websocketx.WebSocketFrame;
import io.netty.util.concurrent.GlobalEventExecutor;
/**
* 自定义的路由 既可以实现http又可以实现socket
*
* @author songyan
*
*/
public class HttpHandler extends SimpleChannelInboundHandler<Object> {
// 用于记录和管理所有客户端的channle
private Channel outboundChannel;
private static ChannelGroup clients = new DefaultChannelGroup(GlobalEventExecutor.INSTANCE);
/**
* 打开链接
*/
@Override
public void channelActive(ChannelHandlerContext ctx) throws Exception {
System.out.println("websocket::::::::::: active");
super.channelActive(ctx);
}
/**
* 获取客户端的channle，添加到ChannelGroup中
*/
@Override
public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
System.out.println("websocket::::::::::: add");
clients.add(ctx.channel());
}
/**
* 从ChannelGroup中移除channel
*/
@Override
public void handlerRemoved(ChannelHandlerContext ctx) throws Exception {
System.out.println("websocket::::::::::: Removed");
}
/**
* 销毁channel
*/
@Override
public void channelInactive(ChannelHandlerContext ctx) throws Exception {
System.out.println("websocket::::::::::: destroyed");
if (clients != null) {
closeOnFlush(outboundChannel);
}
}
/**
* 关闭释放channel
* @param ch
*/
static void closeOnFlush(Channel ch) {
if (ch != null && ch.isActive()) {
ch.writeAndFlush(Unpooled.EMPTY_BUFFER).addListener(ChannelFutureListener.CLOSE);
}
}
@Override
public void channelReadComplete(ChannelHandlerContext ctx) {
ctx.flush();
}
/**
* 异常捕获
*/
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
System.err.println("出错了");
cause.printStackTrace();
ctx.close();
}
/**
* 路由
* 对http，websocket单独处理
*/
@Override
protected void channelRead0(ChannelHandlerContext ctx, Object msg) throws Exception {
if (msg instanceof FullHttpRequest) {// 如果是HTTP请求，进行HTTP操作
handleHttpRequest(ctx, (FullHttpRequest) msg);
} else if (msg instanceof WebSocketFrame) {// 如果是Websocket请求，则进行websocket操作
handleWebSocketFrame(ctx, (WebSocketFrame) msg);
}
}
/**
* 对http请求的处理
*/
private void handleHttpRequest(ChannelHandlerContext ctx, final FullHttpRequest msg) {
final Channel inboundChannel = ctx.channel();
String host = msg.headers().get("Host");
int port = 80;
String pattern = "(http://|https://)?([^:]+)(:[\\d]+)?";
Pattern r = Pattern.compile(pattern);
Matcher m = r.matcher(host);
if (m.find()) {
host = m.group(2);
port = (m.group(3) == null) ? 80 : Integer.parseInt(m.group(3).substring(1));
}
Bootstrap b = new Bootstrap();
b.group(inboundChannel.eventLoop()) // use inboundChannel thread
.channel(ctx.channel().getClass()).handler(new BackendHandlerInitializer(inboundChannel));
ChannelFuture f = b.connect("127.0.0.1", 8015);
outboundChannel = f.channel();
msg.retain();
ChannelFuture channelFuture = f.addListener(new ChannelFutureListener() {
public void operationComplete(ChannelFuture future) throws Exception {
if (future.isSuccess()) {
outboundChannel.writeAndFlush(msg);
} else {
inboundChannel.close();
}
}
});
}
/**
* 对socket请求的处理
*/
private void handleWebSocketFrame(ChannelHandlerContext ctx, WebSocketFrame msg) {
// 获取客户端传输过来的消息
String content = msg.toString();
System.out.println("websocket：：： 接受到的数据：" + content);
clients.writeAndFlush(new TextWebSocketFrame("[服务器在]" + LocalDateTime.now() + "接受到消息, 消息为：" + content));
}
}
原文地址：https://www.cnblogs.com/excellencesy/p/11241063.html
时间： 2024-07-31 18:56:55