关于java:Netty整合SpringMVC实现高效的HTTP服务请求

首先，你必须要理解netty，说简略点：客户端通过TCP链接和服务器建设长连贯，client和server都是通过管道（ChannelPipeline）的addLast办法的增加程序来解决接管或者发送的数据。

这个和struts的filter的doFilter原理相似，解决完一个filter，如果前面还有其余的filter，就将数据chain.doFilter来持续解决。

而后，说说netty怎么来整合springMVC：当client和server建设连贯后，咱们在addLast的某个类中将client发来的申请，让DispatcherServlet来解决，而后将解决后的后果通过ChannelHandlerContext或者Channel将,后果writeAndFlush到client。
1.写一个netty sever的java代码

package com.magic.netty.server;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.web.servlet.DispatcherServlet;import io.netty.bootstrap.ServerBootstrap;import io.netty.channel.ChannelFuture;import io.netty.channel.ChannelOption;import io.netty.channel.EventLoopGroup;import io.netty.channel.nio.NioEventLoopGroup;import io.netty.channel.socket.nio.NioServerSocketChannel;import com.magic.netty.HttpServerInitializer;public class NettyHttpServer { public NettyHttpServer(Integer port) {  this.port = port; } public NettyHttpServer(Integer port, DispatcherServlet servlet) {  this.port = port;  this.servlet = servlet; } public void start(){  EventLoopGroup bossGroup = new NioEventLoopGroup();  EventLoopGroup workerGroup = new NioEventLoopGroup();  try {   ServerBootstrap b = new ServerBootstrap();   b.group(bossGroup, workerGroup)     .channel(NioServerSocketChannel.class)     .childHandler(new HttpServerInitializer(servlet))     .option(ChannelOption.SO_BACKLOG, 128)     .childOption(ChannelOption.SO_KEEPALIVE, true);   System.out.println("NettyHttpServer Run successfully");   // 绑定端口，开始接管进来的连贯   ChannelFuture f = b.bind(port).sync();   // 期待服务器 socket 敞开 。在这个例子中，这不会产生，但你能够优雅地敞开你的服务器。   f.channel().closeFuture().sync();  } catch (Exception e) {   log.error("NettySever start fail",e);  } finally {   workerGroup.shutdownGracefully();   bossGroup.shutdownGracefully();  } } private int port; private static Logger log = LoggerFactory.getLogger(NettyHttpServer.class); private DispatcherServlet servlet;}

2.初始化netty的channel管道

package com.magic.netty;import org.springframework.web.servlet.DispatcherServlet;import io.netty.channel.ChannelInitializer;import io.netty.channel.ChannelPipeline;import io.netty.channel.socket.SocketChannel;import io.netty.handler.codec.http.HttpContentCompressor;import io.netty.handler.codec.http.HttpObjectAggregator;import io.netty.handler.codec.http.HttpRequestDecoder;import io.netty.handler.codec.http.HttpResponseEncoder;import io.netty.handler.stream.ChunkedWriteHandler;public class HttpServerInitializer extends ChannelInitializer<SocketChannel> { public HttpServerInitializer(DispatcherServlet servlet) {  this.servlet = servlet; } public HttpServerInitializer() {   } @Override protected void initChannel(SocketChannel ch) throws Exception {  ChannelPipeline pipeline = ch.pipeline();  pipeline.addLast("decoder", new HttpRequestDecoder());  pipeline.addLast("encoder", new HttpResponseEncoder());  pipeline.addLast("aggregator", new HttpObjectAggregator(2147483647));  pipeline.addLast("chunkedWriter", new ChunkedWriteHandler());        pipeline.addLast("deflater", new HttpContentCompressor());        pipeline.addLast("handler", new HttpRequestHandler(servlet)); } private DispatcherServlet servlet;}

3.在handler外面解决client发来的申请

package com.magic.netty;import java.io.UnsupportedEncodingException;import java.net.URLDecoder;import java.util.HashMap;import java.util.Iterator;import java.util.List;import java.util.Map;import java.util.Map.Entry;import javax.servlet.ServletContext;import io.netty.buffer.ByteBuf;import io.netty.buffer.Unpooled;import io.netty.channel.ChannelFuture;import io.netty.channel.ChannelFutureListener;import io.netty.channel.ChannelHandlerContext;import io.netty.channel.SimpleChannelInboundHandler;import io.netty.handler.codec.http.*;import io.netty.handler.codec.http.multipart.DefaultHttpDataFactory;import io.netty.handler.codec.http.multipart.HttpPostRequestDecoder;import io.netty.handler.codec.http.multipart.InterfaceHttpData;import io.netty.handler.codec.http.multipart.InterfaceHttpData.HttpDataType;import io.netty.handler.codec.http.multipart.MemoryAttribute;import io.netty.util.CharsetUtil;import org.apache.commons.lang3.StringUtils;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.mock.web.MockHttpServletRequest;import org.springframework.mock.web.MockHttpServletResponse;import org.springframework.web.servlet.DispatcherServlet;import org.springframework.web.util.UriComponents;import org.springframework.web.util.UriComponentsBuilder;import org.springframework.web.util.UriUtils;public class HttpRequestHandler extends SimpleChannelInboundHandler<FullHttpRequest> {    public HttpRequestHandler(DispatcherServlet servlet) {  this.servlet = servlet;  this.servletContext = servlet.getServletConfig().getServletContext(); } @Override    public void exceptionCaught(ChannelHandlerContext ctx, Throwable e) throws Exception {     logger.error(e.getMessage(),e);        ctx.close();    }    protected void channelRead0(ChannelHandlerContext ctx, FullHttpRequest fullHttpRequest) throws Exception {     boolean flag = HttpMethod.POST.equals(fullHttpRequest.getMethod())                || HttpMethod.GET.equals(fullHttpRequest.getMethod());                Map<String, String>  parammap = getRequestParams(ctx,fullHttpRequest);        if(flag && ctx.channel().isActive()){            //HTTP申请、GET/POST            MockHttpServletResponse servletResponse = new MockHttpServletResponse();            MockHttpServletRequest servletRequest =new MockHttpServletRequest(servletContext);            // headers            for (String name : fullHttpRequest.headers().names()) {                for (String value : fullHttpRequest.headers().getAll(name)) {                    servletRequest.addHeader(name, value);                }            }            String uri = fullHttpRequest.getUri();            uri = new String(uri.getBytes("ISO8859-1"), "UTF-8");            uri = URLDecoder.decode(uri, "UTF-8");            UriComponents uriComponents = UriComponentsBuilder.fromUriString(uri).build();            String path = uriComponents.getPath();            path = URLDecoder.decode(path, "UTF-8");            servletRequest.setRequestURI(path);            servletRequest.setServletPath(path);            servletRequest.setMethod(fullHttpRequest.getMethod().name());            if (uriComponents.getScheme() != null) {                servletRequest.setScheme(uriComponents.getScheme());            }            if (uriComponents.getHost() != null) {                servletRequest.setServerName(uriComponents.getHost());            }            if (uriComponents.getPort() != -1) {                servletRequest.setServerPort(uriComponents.getPort());            }            ByteBuf content = fullHttpRequest.content();            content.readerIndex(0);            byte[] data = new byte[content.readableBytes()];            content.readBytes(data);            servletRequest.setContent(data);            try {                if (uriComponents.getQuery() != null) {                    String query = UriUtils.decode(uriComponents.getQuery(),"UTF-8");                    servletRequest.setQueryString(query);                }                if(parammap!=null&&parammap.size()>0){                 for (String key : parammap.keySet()) {                        servletRequest.addParameter(UriUtils.decode(key,"UTF-8"), UriUtils.decode(parammap.get(key) == null ? "": parammap.get(key), "UTF-8"));                    }                }                            } catch (UnsupportedEncodingException ex) {             ex.printStackTrace();            }            this.servlet.service(servletRequest,servletResponse);            HttpResponseStatus status = HttpResponseStatus.valueOf(servletResponse.getStatus());            String result = servletResponse.getContentAsString();            result = StringUtils.isEmpty(result)?"":result;            FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, status,Unpooled.copiedBuffer(result,CharsetUtil.UTF_8));            response.headers().set("Content-Type", "text/json;charset=UTF-8");            response.headers().set("Access-Control-Allow-Origin", "*");            response.headers().set("Access-Control-Allow-Headers", "Content-Type,Content-Length, Authorization, Accept,X-Requested-With,X-File-Name");            response.headers().set("Access-Control-Allow-Methods", "PUT,POST,GET,DELETE,OPTIONS");            response.headers().set("Content-Length", Integer.valueOf(response.content().readableBytes()));            response.headers().set("Connection", "keep-alive");            ChannelFuture writeFuture = ctx.writeAndFlush(response);            writeFuture.addListener(ChannelFutureListener.CLOSE);        }    }  /**     * 获取post申请、get申请的参数保留到map中     */    private Map<String, String> getRequestParams(ChannelHandlerContext ctx, HttpRequest req){        Map<String, String>requestParams=new HashMap<String, String>();        // 解决get申请          if (req.getMethod() == HttpMethod.GET) {            QueryStringDecoder decoder = new QueryStringDecoder(req.getUri());              Map<String, List<String>> parame = decoder.parameters();              Iterator<Entry<String, List<String>>> iterator = parame.entrySet().iterator();            while(iterator.hasNext()){                Entry<String, List<String>> next = iterator.next();                requestParams.put(next.getKey(), next.getValue().get(0));            }        }         // 解决POST申请          if (req.getMethod() == HttpMethod.POST) {            HttpPostRequestDecoder decoder = new HttpPostRequestDecoder(                      new DefaultHttpDataFactory(false), req);              List<InterfaceHttpData> postData = decoder.getBodyHttpDatas(); //            for(InterfaceHttpData data:postData){                if (data.getHttpDataType() == HttpDataType.Attribute) {                      MemoryAttribute attribute = (MemoryAttribute) data;                      requestParams.put(attribute.getName(), attribute.getValue());                }            }        }        return requestParams;    } private static final Logger logger = LoggerFactory.getLogger(HttpRequestHandler.class); private final DispatcherServlet servlet; private final ServletContext servletContext;}

4.初始化servlet并启动netty server

package com.magic;import javax.servlet.ServletException;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;import org.springframework.mock.web.MockServletConfig;import org.springframework.web.context.support.XmlWebApplicationContext;import org.springframework.web.servlet.DispatcherServlet;import com.magic.common.config.PropConfig;import com.magic.netty.server.NettyHttpServer;public class MagicWebServer {  private static Logger logger = LoggerFactory.getLogger(MagicWebServer.class); public static void main(String[] args) {  ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");  Integer port = 6001;  DispatcherServlet servlet = getDispatcherServlet(ctx);  NettyHttpServer server = new NettyHttpServer(port,servlet);  server.start();   }  public static DispatcherServlet getDispatcherServlet(ApplicationContext ctx){     XmlWebApplicationContext mvcContext = new XmlWebApplicationContext();  mvcContext.setConfigLocation("classpath:spring-servlet.xml");  mvcContext.setParent(ctx);  MockServletConfig servletConfig = new MockServletConfig(mvcContext.getServletContext(), "dispatcherServlet");  DispatcherServlet dispatcherServlet = new DispatcherServlet(mvcContext);  try {   dispatcherServlet.init(servletConfig);  } catch (ServletException e) {   e.printStackTrace();  }  return dispatcherServlet; }}

5.写一个controller，并测试一波http://127.0.0.1:6001/user/login

package com.magic.controller;import java.util.HashMap;import java.util.Map;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.ResponseBody;import com.alibaba.fastjson.JSONObject;@Controller@RequestMapping(value="/user",produces = "text/json;charset=utf-8")public class UserController extends BaseController{ @RequestMapping("/login") @ResponseBody public String login(String username,String pwd){  JSONObject resultJson = new JSONObject();  Map<String, String> loginResult = new HashMap<String, String>();  loginResult.put("username", username);  loginResult.put("age", "20");  loginResult.put("sex", "boy");    resultJson.put("code", 200);  resultJson.put("msg", "登录胜利");  resultJson.put("result", loginResult);    return JSONObject.toJSONString(resultJson); }}

Mark一下，阐明在coding的时候遇到的问题

代码中的applicationContext.xml和spring-servlet.xml的依照springMVC的失常配置就行
如果返回到client端的代码有中文乱码，那么在requestMapping外面增加produces = “text/json;charset=utf-8”。

起源：blog.csdn.net/shzy1988/article/details/78841140

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