Tomcat8.x 路由表的建立->路由的匹配->Servlet的执行->数据的输出

路由表的建立->路由的匹配->Servlet的执行

//路由表的建立---------------1class org.apache.catalina.core.StandardService{protected void startInternal() throws LifecycleException {//org.apache.catalina.core.StandardEngine//org.apache.catalina.core.StandardHost//org.apache.catalina.core.StandardContext --- context//org.apache.catalina.core.StandardWrapper --- context.addChild(wrapper);//org.apache.tomcat.util.descriptor.web.SessionConfig --- context.getServletContext().getSessionCookieConfig().setXXX(...);//org.apache.tomcat.util.descriptor.web.FilterDef --- context.addFilterDef(filter);//org.apache.tomcat.util.descriptor.web.FilterMap --- context.addFilterMap(filterMap);//<listener-class>cn.java.listener.HelloListener</listener-class> --- context.addApplicationListener(listener);engine.start(); // 查找主机、上下文，构造对象树// 路由表的建立//!!! 查找默认虚拟主机/让 mapperListener 成为StandardEngine、StandardHost、StandardContext的监听器/注册路径信息到mapper中        mapperListener.start(); }}// StandardContext的事件监听器,用来解析上下文class org.apache.catalina.startup.ContextConfig{private void configureContext(WebXml webxml) {// context === org.apache.catalina.core.StandardContext        for (FilterDef filter : webxml.getFilters().values()) { // 过滤器            if (filter.getAsyncSupported() == null) {                filter.setAsyncSupported("false");            }            context.addFilterDef(filter);        }        for (FilterMap filterMap : webxml.getFilterMappings()) { // 过滤器映射            context.addFilterMap(filterMap);        }        for (String listener : webxml.getListeners()) { // 应用监听器            context.addApplicationListener(listener);        }        for (ServletDef servlet : webxml.getServlets().values()) { // 添加Servlet对象        // org.apache.catalina.core.StandardContext.createWrapper();        // 创建org.apache.catalina.core.StandardWrapper对象        // 给wrapper添加生命周期监听器        // 给wrapper添加容器监听器            Wrapper wrapper = context.createWrapper();            // Description is ignored            // Display name is ignored            // Icons are ignored            // jsp-file gets passed to the JSP Servlet as an init-param            if (servlet.getLoadOnStartup() != null) {                wrapper.setLoadOnStartup(servlet.getLoadOnStartup().intValue());            }            if (servlet.getEnabled() != null) {                wrapper.setEnabled(servlet.getEnabled().booleanValue());            }            wrapper.setName(servlet.getServletName()); // servlet的名称            Map<String,String> params = servlet.getParameterMap(); // Servlet的属性            for (Entry<String, String> entry : params.entrySet()) {                wrapper.addInitParameter(entry.getKey(), entry.getValue());            }            wrapper.setRunAs(servlet.getRunAs());            Set<SecurityRoleRef> roleRefs = servlet.getSecurityRoleRefs();            for (SecurityRoleRef roleRef : roleRefs) {                wrapper.addSecurityReference(                        roleRef.getName(), roleRef.getLink());            }            wrapper.setServletClass(servlet.getServletClass()); // Servlet的类名            MultipartDef multipartdef = servlet.getMultipartDef();            if (multipartdef != null) {                if (multipartdef.getMaxFileSize() != null &&                        multipartdef.getMaxRequestSize()!= null &&                        multipartdef.getFileSizeThreshold() != null) {                    wrapper.setMultipartConfigElement(new MultipartConfigElement(                            multipartdef.getLocation(),                            Long.parseLong(multipartdef.getMaxFileSize()),                            Long.parseLong(multipartdef.getMaxRequestSize()),                            Integer.parseInt(                                    multipartdef.getFileSizeThreshold())));                } else {                    wrapper.setMultipartConfigElement(new MultipartConfigElement(                            multipartdef.getLocation()));                }            }            if (servlet.getAsyncSupported() != null) {                wrapper.setAsyncSupported(                        servlet.getAsyncSupported().booleanValue());            }            wrapper.setOverridable(servlet.isOverridable());            // wrapper ===  org.apache.catalina.core.StandardWrapper            context.addChild(wrapper);        }        for (Entry<String, String> entry :                webxml.getServletMappings().entrySet()) { // 添加Servlet映射            context.addServletMapping(entry.getKey(), entry.getValue());        }        SessionConfig sessionConfig = webxml.getSessionConfig();        if (sessionConfig != null) { // session配置            if (sessionConfig.getSessionTimeout() != null) {                context.setSessionTimeout(                        sessionConfig.getSessionTimeout().intValue());            }            SessionCookieConfig scc =                context.getServletContext().getSessionCookieConfig();//!!!            scc.setName(sessionConfig.getCookieName());            scc.setDomain(sessionConfig.getCookieDomain());            scc.setPath(sessionConfig.getCookiePath());            scc.setComment(sessionConfig.getCookieComment());            if (sessionConfig.getCookieHttpOnly() != null) {                scc.setHttpOnly(sessionConfig.getCookieHttpOnly().booleanValue());            }            if (sessionConfig.getCookieSecure() != null) {                scc.setSecure(sessionConfig.getCookieSecure().booleanValue());            }            if (sessionConfig.getCookieMaxAge() != null) {                scc.setMaxAge(sessionConfig.getCookieMaxAge().intValue());            }            if (sessionConfig.getSessionTrackingModes().size() > 0) {                context.getServletContext().setSessionTrackingModes(                        sessionConfig.getSessionTrackingModes());            }        }}}class org.apache.catalina.mapper.MapperListener{// 路由表的建立public void startInternal() throws LifecycleException {setState(LifecycleState.STARTING);        Engine engine = service.getContainer(); // org.apache.catalina.core.StandardEngine        if (engine == null) {            return;        }        findDefaultHost(); // 查找默认虚拟主机        addListeners(engine);// 让自己成为StandardEngine、StandardHost、StandardContext的监听器        Container[] conHosts = engine.findChildren();  // 注册路径信息到mapper中        for (Container conHost : conHosts) { //             Host host = (Host) conHost; // org.apache.catalina.core.StandardHost            if (!LifecycleState.NEW.equals(host.getState())) {                // Registering the host will register the context and wrappers                registerHost(host);            }        }}// 添加虚拟主机private void registerHost(Host host) {String[] aliases = host.findAliases(); // org.apache.catalina.core.StandardHost        mapper.addHost(host.getName(), aliases, host); // mapper.hosts        for (Container container : host.findChildren()) {            if (container.getState().isAvailable()) { // org.apache.catalina.core.StandardContext                registerContext((Context) container);            }        }}// 添加上下文private void registerContext(Context context) {String contextPath = context.getPath();        if ("/".equals(contextPath)) {            contextPath = "";        }        Host host = (Host)context.getParent(); // org.apache.catalina.core.StandardHost        WebResourceRoot resources = context.getResources();        String[] welcomeFiles = context.findWelcomeFiles();        List<WrapperMappingInfo> wrappers = new ArrayList<>();        for (Container container : context.findChildren()) { // org.apache.catalina.core.StandardWrapper列表            prepareWrapperMappingInfo(context, (Wrapper) container, wrappers);        }        // 添加到map        mapper.addContextVersion(host.getName(), host, contextPath,                context.getWebappVersion(), context, welcomeFiles, resources,                wrappers);}private void prepareWrapperMappingInfo(Context context, Wrapper wrapper,            List<WrapperMappingInfo> wrappers) {        String wrapperName = wrapper.getName();// Servlet名称<servlet-name></servlet-name>        boolean resourceOnly = context.isResourceOnlyServlet(wrapperName);        String[] mappings = wrapper.findMappings();        for (String mapping : mappings) {            boolean jspWildCard = (wrapperName.equals("jsp")                                   && mapping.endsWith("/*"));            wrappers.add(new WrapperMappingInfo(mapping, wrapper, jspWildCard,                    resourceOnly));        }    }}// 路由表的映射---------------2class org.apache.catalina.connector.CoyoteAdapter{public void service(org.apache.coyote.Request req,        org.apache.coyote.Response res)        throws Exception {postParseSuccess = postParseRequest(req, request, res, response);//!!!!   解析scheme、查找路由、sessionID// request.getMappingData() 内部存储路由映射对象和StandardWrapper对象(StandardWrapper是Servlet的包装器)}// 解析请求protected boolean postParseRequest(org.apache.coyote.Request req, Request request,            org.apache.coyote.Response res, Response response) throws IOException, ServletException {    connector.getService().getMapper().map(serverName, decodedURI,            version, request.getMappingData()); // 映射出路由 -------------------并创建出相应对象!!!!}}// 路由映射class  org.apache.catalina.mapper.Mapper{public void map(MessageBytes host, MessageBytes uri, String version,                 MappingData mappingData) throws IOException {        internalMap(host.getCharChunk(), uri.getCharChunk(), version,                mappingData);    }// 查找虚拟主机的映射，设置到mappingData.host// 查找上下文路径的映射，设置到mappingData.contextPath// 查找上下文的映射，设置到mappingData.context// 查找Servlet的映射，设置到mappingData.wrapperprivate final void internalMap(CharChunk host, CharChunk uri,            String version, MappingData mappingData) throws IOException {// Virtual host mapping 查找主机映射        MappedHost[] hosts = this.hosts;        MappedHost mappedHost = exactFindIgnoreCase(hosts, host);        mappingData.host = mappedHost.object;                // Context mapping 上下文映射        ContextList contextList = mappedHost.contextList; // 虚拟主机的目录列表        MappedContext[] contexts = contextList.contexts;        // ...        mappingData.contextPath.setString(context.name); // 上下文地址                ContextVersion contextVersion = null;        ContextVersion[] contextVersions = context.versions; // 上下文版本列表        mappingData.context = contextVersion.object;        mappingData.contextSlashCount = contextVersion.slashCount;                // Wrapper mapping  Servlet的映射        if (!contextVersion.isPaused()) {            internalMapWrapper(contextVersion, uri, mappingData);        }}// 查找Servlet的映射，设置到mappingData.wrapperprivate final void internalMapWrapper(ContextVersion contextVersion,                 CharChunk path,                 MappingData mappingData) throws IOException {// Rule 1 -- Exact Match  Servlet的匹配        MappedWrapper[] exactWrappers = contextVersion.exactWrappers;        internalMapExactWrapper(exactWrappers, path, mappingData);        if (mappingData.wrapper == null) {        //....        }        // ....}}// Servlet的执行---------------3class org.apache.catalina.connector.CoyoteAdapter{public void service(org.apache.coyote.Request req,        org.apache.coyote.Response res)        throws Exception {// 执行管道链条                // org.apache.catalina.core.StandardService --- getService()                // org.apache.catalina.core.StandardEngine --- getContainer()                // org.apache.catalina.core.StandardPipeline --- getPipeline()                // org.apache.catalina.core.StandardEngineValve --- getFirst()                connector.getService().getContainer().getPipeline().getFirst().invoke(request, response);                request.finishRequest();                response.finishResponse(); // 输出数据,并关闭输出流}}class org.apache.catalina.core.StandardEngineValve{public final void invoke(Request request, Response response)        throws IOException, ServletException {// org.apache.catalina.core.StandardHostValve        host.getPipeline().getFirst().invoke(request, response);}}class org.apache.catalina.core.StandardHostValve{public final void invoke(Request request, Response response)throws IOException, ServletException {// org.apache.catalina.core.StandardContextValve                context.getPipeline().getFirst().invoke(request, response); //!!!!                                response.setSuspended(false); }}class org.apache.catalina.core.StandardContextValve{// request === org.apache.catalina.connector.RequestWrapper wrapper = request.getWrapper(); // Servlet对象// 执行Servlet请求 !!!! wrapper === org.apache.catalina.core.StandardWrapper        // org.apache.catalina.core.StandardWrapperValve.invoke(request, response);        wrapper.getPipeline().getFirst().invoke(request, response);}// class org.apache.catalina.connector.Request{    public Wrapper getWrapper() {            return mappingData.wrapper;        }    public MappingData getMappingData() {            return mappingData;        }    }