tomcat阅读第十三篇(tomcat ContextConfig(configureStart[Webconfig]))
这篇单独分析configureStart –>webconfig方法,下面是configureStart的代码
protected synchronized void configureStart() { // Called from StandardContext.start() if (log.isDebugEnabled()) { log.debug(sm.getString("contextConfig.start")); } if (log.isDebugEnabled()) { log.debug(sm.getString("contextConfig.xmlSettings", context.getName(), Boolean.valueOf(context.getXmlValidation()), Boolean.valueOf(context.getXmlNamespaceAware()))); } webConfig(); if (!context.getIgnoreAnnotations()) { applicationAnnotationsConfig(); } if (ok) { validateSecurityRoles(); } // Configure an authenticator if we need one if (ok) { authenticatorConfig(); } …………………………. }
WebConfig方法：
protected void webConfig() { //创建WebXmlParser解析web.xml配置文件，实例化WebXml类 start //goto 解析WebXmlParser WebXmlParser webXmlParser = new WebXmlParser(context.getXmlNamespaceAware(), context.getXmlValidation(), context.getXmlBlockExternal()); //goto分析解析WebXmlFragment Set<WebXml> defaults = new HashSet<>(); defaults.add(getDefaultWebXmlFragment(webXmlParser)); //goto分析解析ContextWebXml WebXml webXml = createWebXml(); InputSource contextWebXml = getContextWebXmlSource(); if (!webXmlParser.parseWebXml(contextWebXml, webXml, false)) { ok = false; } //创建WebXmlParser解析web.xml配置文件，实例化WebXml类 End ServletContext sContext = context.getServletContext(); // Ordering is important here // Step 1. Identify all the JARs packaged with the application and those // provided by the container. If any of the application JARs have a // web-fragment.xml it will be parsed at this point. web-fragment.xml // files are ignored for container provided JARs. //goto分析step1 Map<String,WebXml> fragments = processJarsForWebFragments(webXml, webXmlParser); // Step 2. Order the fragments. //goto分析step2 Set<WebXml> orderedFragments = null; orderedFragments = WebXml.orderWebFragments(webXml, fragments, sContext); // Step 3. Look for ServletContainerInitializer implementations //goto分析step3 if (ok) { processServletContainerInitializers(); } if (!webXml.isMetadataComplete() || typeInitializerMap.size() > 0) { // Step 4. Process /WEB-INF/classes for annotations and // @HandlesTypes matches //goto分析step4 Map<String,JavaClassCacheEntry> javaClassCache = new HashMap<>(); if (ok) { WebResource[] webResources = context.getResources().listResources("/WEB-INF/classes"); for (WebResource webResource : webResources) { // Skip the META-INF directory from any JARs that have been // expanded in to WEB-INF/classes (sometimes IDEs do this). if ("META-INF".equals(webResource.getName())) { continue; } processAnnotationsWebResource(webResource, webXml, webXml.isMetadataComplete(), javaClassCache); } } // Step 5. Process JARs for annotations and // @HandlesTypes matches - only need to process those fragments we // are going to use (remember orderedFragments includes any // container fragments) if (ok) { processAnnotations( orderedFragments, webXml.isMetadataComplete(), javaClassCache); } // Cache, if used, is no longer required so clear it javaClassCache.clear(); } if (!webXml.isMetadataComplete()) { //goto 分析step6~9 // Step 6. Merge web-fragment.xml files into the main web.xml // file. if (ok) { ok = webXml.merge(orderedFragments); } // Step 7. Apply global defaults // Have to merge defaults before JSP conversion since defaults // provide JSP servlet definition. webXml.merge(defaults); // Step 8. Convert explicitly mentioned jsps to servlets if (ok) { convertJsps(webXml); } // Step 9. Apply merged web.xml to Context if (ok) { configureContext(webXml); } } else { webXml.merge(defaults); convertJsps(webXml); configureContext(webXml); } if (context.getLogEffectiveWebXml()) { log.info("web.xml:\n" + webXml.toXml()); } // Always need to look for static resources // Step 10. Look for static resources packaged in JARs //goto分析step10 if (ok) { // Spec does not define an order. // Use ordered JARs followed by remaining JARs Set<WebXml> resourceJars = new LinkedHashSet<>(); for (WebXml fragment : orderedFragments) { resourceJars.add(fragment); } for (WebXml fragment : fragments.values()) { if (!resourceJars.contains(fragment)) { resourceJars.add(fragment); } } processResourceJARs(resourceJars); // See also StandardContext.resourcesStart() for // WEB-INF/classes/META-INF/resources configuration } // Step 11. Apply the ServletContainerInitializer config to the // context //goto分析step11 if (ok) { for (Map.Entry<ServletContainerInitializer, Set<Class<?>>> entry : initializerClassMap.entrySet()) { if (entry.getValue().isEmpty()) { context.addServletContainerInitializer( entry.getKey(), null); } else { context.addServletContainerInitializer( entry.getKey(), entry.getValue()); } } } }
1. 解析WebXmlParser：WebXmlParser解析填充webxml对象分析，先看WebXmlParser代码，看源码可以发现是同样是通过Digester来解析webxml的配置，下面是WebXmlParser的构造方法，可以方法跟web解析相关的rule是WebRuleSet，现在来看WebRuleSet的addRuleInstances
public WebXmlParser(boolean namespaceAware, boolean validation, boolean blockExternal) { //创建web-app的Digester webRuleSet = new WebRuleSet(false); webDigester = DigesterFactory.newDigester(validation, namespaceAware, webRuleSet, blockExternal); webDigester.getParser(); //创建web-fragment的Digester webFragmentRuleSet = new WebRuleSet(true); webFragmentDigester = DigesterFactory.newDigester(validation, namespaceAware, webFragmentRuleSet, blockExternal); webFragmentDigester.getParser(); } //WebXml会作为根对象push进Digester类 WebRuleSet的addRuleInstances方法： public void addRuleInstances(Digester digester) { // SetPublicIdRule 的作用是解析到web-app或者web-fragment的时候，调用WebXml的SetPublicIdRule方法，传入Digester解析得到的publicId digester.addRule(fullPrefix, new SetPublicIdRule("setPublicId")); // IgnoreAnnotationsRule 调用WebXml对象的setMetadataComplete，web-app标签metadata-complete的属性值作为参数 digester.addRule(fullPrefix, new IgnoreAnnotationsRule()); // VersionRule调用WebXml对象的setVersion，web-app标签version属性值作为参数 digester.addRule(fullPrefix, new VersionRule()); // AbsoluteOrderingRule，实例化WebXml类的absoluteOrdering 属性，什么作用后面可以看到 digester.addRule(fullPrefix + "/absolute-ordering", absoluteOrdering); //打印log的一个rule，如果不是fragment，则会打警告的log digester.addRule(fullPrefix + "/ordering", relativeOrdering); if (fragment) { //解析到web-fragment/name的时候，调用WebXml的setName方法，传入name标签的body text(<name>xxxs</name>) digester.addRule(fullPrefix + "/name", name); //解析到web-fragment/ ordering/after/name的時候，调用WebXml的addAfterOrdering，传入标签的body text digester.addCallMethod(fullPrefix + "/ordering/after/name", "addAfterOrdering", 0); digester.addCallMethod(fullPrefix + "/ordering/after/others", "addAfterOrderingOthers"); digester.addCallMethod(fullPrefix + "/ordering/before/name", "addBeforeOrdering", 0); digester.addCallMethod(fullPrefix + "/ordering/before/others", "addBeforeOrderingOthers"); //以上同解析web-fragment/ ordering/after/name标签 } else { //解析到web-xml/absolute-ordering/name,调用WebXml的addAbsoluteOrdering方法，传入标签的body text digester.addCallMethod(fullPrefix + "/absolute-ordering/name", "addAbsoluteOrdering", 0); //解析到web-xml/absolute-ordering/ others,调用WebXml的addAbsoluteOrderingOthers方法，传入标签的body text digester.addCallMethod(fullPrefix + "/absolute-ordering/others", "addAbsoluteOrderingOthers"); //解析到web-xml/ deny-uncovered-http-methods，SetDenyUncoveredHttpMethodsRule rule调用WebXml的setDenyUncoveredHttpMethods方法，设置为true digester.addRule(fullPrefix + "/deny-uncovered-http-methods", new SetDenyUncoveredHttpMethodsRule()); } //解析到web-xml(web-fragement下同)/ context-param结束标签，调用WebXml的addContextParam方法，传入之前push进的param digester.addCallMethod(fullPrefix + "/ context-param ", "addContextParam", 2); //解析到xx/context-param/param-name，push进digester的parameters，作为之前方法的第一个参数 digester.addCallParam(fullPrefix + "/context-param/param-name", 0); //解析到xx/context-param/ param-value，push进digester的parameters，作为之前方法的第二个参数 digester.addCallParam(fullPrefix + "/context-param/param-value", 1); //解析到xx/display-name，调用WebXml方法setDisplayName，传入标签的body text digester.addCallMethod(fullPrefix + "/display-name", "setDisplayName", 0); //解析到xx/ distributable，SetDistributableRule rule 调用WebXml的setDistributable，设置true digester.addRule(fullPrefix + "/distributable", new SetDistributableRule ()); //这个是有关ejb的rule，分析ejb的时候，重点分析 configureNamingRules(digester); //解析到xx/ error-page，创建对象org.apache.tomcat.util.descriptor.web.ErrorPage digester.addObjectCreate(fullPrefix + "/error-page", "org.apache.tomcat.util.descriptor.web.ErrorPage"); //解析到xx/ error-page，调用WebXml的addErrorPage，传入之前ObjectCreateRule创建的对象 digester.addSetNext(fullPrefix + "/error-page", "addErrorPage", "org.apache.tomcat.util.descriptor.web.ErrorPage"); //解析到xx/error-page/error-code，调用ErrorPage的setErrorCode，传入body text digester.addCallMethod(fullPrefix + "/error-page/error-code", "setErrorCode", 0); //解析到xx/error-page/ exception-type，调用ErrorPage的setExceptionType，传入body text digester.addCallMethod(fullPrefix + "/error-page/exception-type", "setExceptionType", 0); //解析到xx/error-page/ location，调用ErrorPage的setLocation，传入body text digester.addCallMethod(fullPrefix + "/error-page/location", "setLocation", 0); //解析到xx/ filter，创建对象org.apache.tomcat.util.descriptor.web.FilterDef digester.addObjectCreate(fullPrefix + "/filter", "org.apache.tomcat.util.descriptor.web.FilterDef"); //解析到xx/ filter，调用WebXml的addFilter，传入之前创建的FilterDef对象 digester.addSetNext(fullPrefix + "/filter", "addFilter", "org.apache.tomcat.util.descriptor.web.FilterDef"); //解析到xx/ filter/ description，调用FilterDef的setDescription方法，传入body text digester.addCallMethod(fullPrefix + "/filter/description", "setDescription", 0); //解析到xx/ filter/ display-name，调用FilterDef的setDisplayName方法，传入body text digester.addCallMethod(fullPrefix + "/filter/display-name", "setDisplayName", 0); //解析到xx/ filter/filter-class，调用FilterDef的setFilterClass方法，传入body text digester.addCallMethod(fullPrefix + "/filter/filter-class", "setFilterClass", 0); //解析到xx/ filter/ filter-name，调用FilterDef的setFilterName方法，传入body text digester.addCallMethod(fullPrefix + "/filter/filter-name", "setFilterName", 0); //解析到xx/ filter/ icon/large-icon，调用FilterDef的setLargeIcon方法，传入body text digester.addCallMethod(fullPrefix + "/filter/icon/large-icon", "setLargeIcon", 0); //解析到xx/ filter/ icon/ small-icon，调用FilterDef的setSmallIcon方法，传入body text digester.addCallMethod(fullPrefix + "/filter/icon/small-icon", "setSmallIcon", 0); //解析到xx/ filter/ async-supported，调用FilterDef的setAsyncSupported方法，传入body text digester.addCallMethod(fullPrefix + "/filter/async-supported", "setAsyncSupported", 0); //解析到xx/filter/init-param結束标签，调用FilterDef的addInitParameter方法，传入之前push的parameters里的参数 digester.addCallMethod(fullPrefix + "/filter/init-param", "addInitParameter", 2); //解析到xx/filter/init-param/param-name，push进digester的parameters，作为addInitParameter的第一个参数 digester.addCallParam(fullPrefix + "/filter/init-param/param-name", 0); //解析到xx/filter/init-param/param-value，push进digester的parameters，作为addInitParameter的第二个参数 digester.addCallParam(fullPrefix + "/filter/init-param/param-value", 1); //解析到xx/filter-mapping，创建对象org.apache.tomcat.util.descriptor.web.FilterMap digester.addObjectCreate(fullPrefix + "/filter-mapping", "org.apache.tomcat.util.descriptor.web.FilterMap"); //解析到xx/ filter-mapping，调用WebXml的addFilterMapping，传入之前创建的对象FilterMap digester.addSetNext(fullPrefix + "/filter-mapping", "addFilterMapping", "org.apache.tomcat.util.descriptor.web.FilterMap"); //解析到xx/filter-mapping/filter-name，调用FilterMap的setFilterName，传入这个标签的body text digester.addCallMethod(fullPrefix + "/filter-mapping/filter-name", "setFilterName", 0); //解析到xx/filter-mapping/ servlet-name，调用FilterMap的addServletName，传入这个标签的body text digester.addCallMethod(fullPrefix + "/filter-mapping/servlet-name", "addServletName", 0); //解析到xx/filter-mapping/ url-pattern，调用FilterMap的addURLPattern，传入这个标签的body text digester.addCallMethod(fullPrefix + "/filter-mapping/url-pattern", "addURLPattern", 0); //解析到xx/filter-mapping/ dispatcher，调用FilterMap的setDispatcher，传入这个标签的body text digester.addCallMethod(fullPrefix + "/filter-mapping/dispatcher", "setDispatcher", 0); //解析到xx/listener/listener-class，调用WebXml的addListener方法，传入标签的body text digester.addCallMethod(fullPrefix + "/listener/listener-class", "addListener", 0); //解析到xx/ jsp-config，SetJspConfig rule判断是否是只配置一个jsp-config digester.addRule(fullPrefix + "/jsp-config", jspConfig); //解析到xx/ jsp-config/jsp-property-group，创建对象org.apache.tomcat.util.descriptor.web.JspPropertyGroup digester.addObjectCreate(fullPrefix + "/jsp-config/jsp-property-group", "org.apache.tomcat.util.descriptor.web.JspPropertyGroup"); //解析到xx/jsp-config/jsp-property-group，调用WebXml的addJspPropertyGroup，传入之前创建的对象JspPropertyGroup digester.addSetNext(fullPrefix + "/jsp-config/jsp-property-group", "addJspPropertyGroup", "org.apache.tomcat.util.descriptor.web.JspPropertyGroup"); //解析到xx/jsp-config/ jsp-property-group/deferred-syntax-allowed-as-literal，调用JspPropertyGroup的setDeferredSyntax方法，传入body text digester.addCallMethod(fullPrefix + "/jsp-config/jsp-property-group/deferred-syntax-allowed-as-literal", "setDeferredSyntax", 0); //解析到xx/jsp-config/ jsp-property-group/ el-ignored，调用JspPropertyGroup的setElIgnored方法，传入body text digester.addCallMethod(fullPrefix + "/jsp-config/jsp-property-group/el-ignored", "setElIgnored", 0); //解析到xx/jsp-config/ jsp-property-group/include-coda，调用JspPropertyGroup的addIncludeCoda方法，传入body text digester.addCallMethod(fullPrefix + "/jsp-config/jsp-property-group/include-coda", "addIncludeCoda", 0); //解析到xx/jsp-config/ jsp-property-group/include- prelude，调用JspPropertyGroup的addIncludePrelude方法，传入body text digester.addCallMethod(fullPrefix + "/jsp-config/jsp-property-group/include-prelude", "addIncludePrelude", 0); //解析到xx/jsp-config/ jsp-property-group/is-xml，调用JspPropertyGroup的setIsXml方法，传入body text digester.addCallMethod(fullPrefix + "/jsp-config/jsp-property-group/is-xml", "setIsXml", 0); //解析到xx/jsp-config/ jsp-property-group/page-encoding，调用JspPropertyGroup的setPageEncoding方法，传入body text digester.addCallMethod(fullPrefix + "/jsp-config/jsp-property-group/page-encoding", "setPageEncoding", 0); //解析到xx/jsp-config/ jsp-property-group/scripting-invalid，调用JspPropertyGroup的setScriptingInvalid方法，传入body text digester.addCallMethod(fullPrefix + "/jsp-config/jsp-property-group/scripting-invalid", "setScriptingInvalid", 0); //解析到xx/jsp-config/ jsp-property-group/ trim-directive-whitespaces，调用JspPropertyGroup的setTrimWhitespace方法，传入body text digester.addCallMethod(fullPrefix + "/jsp-config/jsp-property-group/trim-directive-whitespaces", "setTrimWhitespace", 0); //解析到xx/jsp-config/ jsp-property-group/url-pattern，调用JspPropertyGroup的addUrlPattern方法，传入body text digester.addCallMethod(fullPrefix + "/jsp-config/jsp-property-group/url-pattern", "addUrlPattern", 0); //解析到xx/jsp-config/ jsp-property-group/ default-content-type，调用JspPropertyGroup的setDefaultContentType方法，传入body text digester.addCallMethod(fullPrefix + "/jsp-config/jsp-property-group/default-content-type", "setDefaultContentType", 0); //解析到xx/jsp-config/ jsp-property-group/ buffer，调用JspPropertyGroup的setBuffer方法，传入body text digester.addCallMethod(fullPrefix + "/jsp-config/jsp-property-group/buffer", "setBuffer", 0); //解析到xx/jsp-config/ jsp-property-group/ error-on-undeclared-namespace，调用JspPropertyGroup的setErrorOnUndeclaredNamespace方法，传入body text digester.addCallMethod(fullPrefix + "/jsp-config/jsp-property-group/error-on-undeclared-namespace", "setErrorOnUndeclaredNamespace", 0); //解析到xx/ login-config，SetLoginConfig rule 判断是否只有个login-config配置 digester.addRule(fullPrefix + "/login-config", loginConfig); //解析到xx/ login-config，创建对象org.apache.tomcat.util.descriptor.web.LoginConfig digester.addObjectCreate(fullPrefix + "/login-config", "org.apache.tomcat.util.descriptor.web.LoginConfig"); //解析到xx/ login-config，调用WebXml的setLoginConfig方法，传入之前创建的对象LoginConfig digester.addSetNext(fullPrefix + "/login-config", "setLoginConfig", "org.apache.tomcat.util.descriptor.web.LoginConfig"); //解析到xx/ login-config/ auth-method，调用对象LoginConfig的setAuthMethod，传入标签的body text digester.addCallMethod(fullPrefix + "/login-config/auth-method", "setAuthMethod", 0); //解析到xx/ login-config/ realm-name，调用对象LoginConfig的setRealmName，传入标签的body text digester.addCallMethod(fullPrefix + "/login-config/realm-name", "setRealmName", 0); //解析到xx/ login-config/ form-login-config/form-error-page，调用对象LoginConfig的setErrorPage，传入标签的body text digester.addCallMethod(fullPrefix + "/login-config/form-login-config/form-error-page", "setErrorPage", 0); //解析到xx/ login-config/ form-login-config/ form-login-page，调用对象LoginConfig的setLoginPage，传入标签的body text digester.addCallMethod(fullPrefix + "/login-config/form-login-config/form-login-page", "setLoginPage", 0); //解析到xx/ mime-mapping結束标签，调用WebXml的addMimeMapping，传入参数digester的parameters digester.addCallMethod(fullPrefix + "/mime-mapping", "addMimeMapping", 2); //解析到xx/ mime-mapping/ extension，push进digester的paramters（body text），作为第一个参数 digester.addCallParam(fullPrefix + "/mime-mapping/extension", 0); //解析到xx/ mime-mapping/ mime-type，push进digester的paramters（body text），作为第二个参数 digester.addCallParam(fullPrefix + "/mime-mapping/mime-type", 1); //解析到xx/ security-constraint，创建对象org.apache.tomcat.util.descriptor.web.SecurityConstraint digester.addObjectCreate(fullPrefix + "/security-constraint", "org.apache.tomcat.util.descriptor.web.SecurityConstraint"); //解析到xx/ security-constraint，调用WebXml的addSecurityConstraint，传入对象SecurityConstraint digester.addSetNext(fullPrefix + "/security-constraint", "addSecurityConstraint", "org.apache.tomcat.util.descriptor.web.SecurityConstraint"); //解析到xx/ security-constraint/auth-constraint，SetAuthConstraintRule rule 调用SecurityConstraint的setAuthConstraint方法，设置true digester.addRule(fullPrefix + "/security-constraint/auth-constraint", new SetAuthConstraintRule()); //解析到xx/ security-constraint/ auth-constraint/role-name，调用SecurityConstraint的addAuthRole方法，传入标签的body text digester.addCallMethod(fullPrefix + "/security-constraint/auth-constraint/role-name", "addAuthRole", 0); //解析到xx/ security-constraint/ display-name，调用SecurityConstraint的setDisplayName方法，传入标签的body text digester.addCallMethod(fullPrefix + "/security-constraint/display-name", "setDisplayName", 0); //解析到xx/ security-constraint/ user-data-constraint/transport-guarantee，调用SecurityConstraint的setUserConstraint方法，传入标签的body text digester.addCallMethod(fullPrefix + "/security-constraint/user-data-constraint/transport-guarantee", "setUserConstraint", 0); //解析到xx/ security-constraint/ web-resource-collection，创建对象org.apache.tomcat.util.descriptor.web.SecurityCollection digester.addObjectCreate(fullPrefix + "/security-constraint/web-resource-collection", "org.apache.tomcat.util.descriptor.web.SecurityCollection"); //解析到xx/ security-constraint/ web-resource-collection，调用SecurityConstraint的addCollection，传入之前创建的对象SecurityCollection digester.addSetNext(fullPrefix + "/security-constraint/web-resource-collection", "addCollection", "org.apache.tomcat.util.descriptor.web.SecurityCollection"); //解析到xx/ security-constraint/ web-resource-collection/http-method，调用SecurityCollection的addMethod，传入标签的body text digester.addCallMethod(fullPrefix + "/security-constraint/web-resource-collection/http-method", "addMethod", 0); //解析到xx/ security-constraint/ web-resource-collection/ http-method-omission，调用SecurityCollection的addOmittedMethod，传入标签的body text digester.addCallMethod(fullPrefix + "/security-constraint/web-resource-collection/http-method-omission", "addOmittedMethod", 0); //解析到xx/ security-constraint/ web-resource-collection/url-pattern，调用SecurityCollection的addPattern，传入标签的body text digester.addCallMethod(fullPrefix + "/security-constraint/web-resource-collection/url-pattern", "addPattern", 0); //解析到xx/ security-constraint/ web-resource-collection/ web-resource-name，调用SecurityCollection的setName，传入标签的body text digester.addCallMethod(fullPrefix + "/security-constraint/web-resource-collection/web-resource-name", "setName", 0); //解析到xx/security-role/role-name，调用WebXml的addSecurityRole，传入标签的body text digester.addCallMethod(fullPrefix + "/security-role/role-name", "addSecurityRole", 0); //解析到xx/servlet，ServletDefCreateRule rule push进Digester对象org.apache.tomcat.util.descriptor.web. ServletDef digester.addRule(fullPrefix + "/servlet", new ServletDefCreateRule()); //解析到xx/servlet,调用WebXml的addServlet，传入之前创建的对象ServletDef digester.addSetNext(fullPrefix + "/servlet", "addServlet", "org.apache.tomcat.util.descriptor.web.ServletDef"); //解析到xx/servlet/init-param结束标签，调用ServletDef的addInitParameter，参数是之前push进digester的parameters digester.addCallMethod(fullPrefix + "/servlet/init-param", "addInitParameter", 2); //解析到xx/servlet/init-param/param-name，push进digester的parameters，作为第一个参数 digester.addCallParam(fullPrefix + "/servlet/init-param/param-name", 0); //解析到xx/servlet/init-param/param-name，push进digester的parameters，作为第二个参数 digester.addCallParam(fullPrefix + "/servlet/init-param/param-value", 1); //解析到xx/servlet/ jsp-file标签，调用ServletDef的setJspFile，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/jsp-file", "setJspFile", 0); //解析到xx/servlet/ load-on-startup标签，调用ServletDef的setLoadOnStartup，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/load-on-startup", "setLoadOnStartup", 0); //解析到xx/servlet/ run-as/role-name标签，调用ServletDef的setRunAs，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/run-as/role-name", "setRunAs", 0); //解析到xx/servlet/ security-role-ref，创建对象org.apache.tomcat.util.descriptor.web.SecurityRoleRef digester.addObjectCreate(fullPrefix + "/servlet/security-role-ref", "org.apache.tomcat.util.descriptor.web.SecurityRoleRef"); //解析到xx/servlet/ security-role-ref，调用ServletDef的addSecurityRoleRef，传入对象SecurityRoleRef digester.addSetNext(fullPrefix + "/servlet/security-role-ref", "addSecurityRoleRef", "org.apache.tomcat.util.descriptor.web.SecurityRoleRef"); //解析到xx/servlet/ security-role-ref/role-link，调用SecurityRoleRef的setLink，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/security-role-ref/role-link", "setLink", 0); //解析到xx/servlet/ security-role-ref/ role-name，调用SecurityRoleRef的setName，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/security-role-ref/role-name", "setName", 0); //解析到xx/servlet/servlet-class，调用ServletDef的setServletClass，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/servlet-class", "setServletClass", 0); //解析到xx/servlet/ servlet-name，调用ServletDef的setServletName，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/servlet-name", "setServletName", 0); //解析到xx/servlet/ multipart-config，创建org.apache.tomcat.util.descriptor.web.MultipartDef对象 digester.addObjectCreate(fullPrefix + "/servlet/multipart-config", "org.apache.tomcat.util.descriptor.web.MultipartDef"); //解析到xx/servlet/ multipart-config，调用ServletDef的setMultipartDef，传入之前创建的对象MultipartDef digester.addSetNext(fullPrefix + "/servlet/multipart-config", "setMultipartDef", "org.apache.tomcat.util.descriptor.web.MultipartDef"); //解析到xx/servlet/ multipart-config/location，调用MultipartDef的setLocation方法，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/multipart-config/location", "setLocation", 0); //解析到xx/servlet/ multipart-config/ max-file-size，调用MultipartDef的setMaxFileSize方法，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/multipart-config/max-file-size", "setMaxFileSize", 0); //解析到xx/servlet/ multipart-config/ max-request-size，调用MultipartDef的setMaxRequestSize方法，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/multipart-config/max-request-size", "setMaxRequestSize", 0); //解析到xx/servlet/ multipart-config/ file-size-threshold，调用MultipartDef的setFileSizeThreshold方法，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/multipart-config/file-size-threshold", "setFileSizeThreshold", 0); //解析到xx/servlet/async-supported，调用ServletDef的setAsyncSupported方法，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/async-supported", "setAsyncSupported", 0); //解析到xx/ servlet/enabled，调用ServletDef的setEnabled方法，传入标签的body text digester.addCallMethod(fullPrefix + "/servlet/enabled", "setEnabled", 0); //解析到xx/servlet-mapping结束标签，调用WebXml的方法addServletMapping，传入之前push 进digester的parameters，CallMethodMultiRule的第三个参数0是parameters里的param index，这个param是ArrayList digester.addRule(fullPrefix + "/servlet-mapping", new CallMethodMultiRule("addServletMapping", 2, 0)); //解析到xx/servlet-mapping/servlet-name，push进digester的parameters，参数是servlet-name标签的body text digester.addCallParam(fullPrefix + "/servlet-mapping/servlet-name", 1); //解析到xx/ servlet-mapping/url-pattern，push进digester的parameters，push进的param是ArrayList，参数0是push进parameters的参数的index digester.addRule(fullPrefix + "/servlet-mapping/url-pattern", new CallParamMultiRule(0)); //解析到xx/session-config，SetSessionConfig rule，判断是否只有1次配置，只能配置一个 digester.addRule(fullPrefix + "/session-config ", sessionConfig); //解析到xx/session-config，创建对象org.apache.tomcat.util.descriptor.web.SessionConfig digester.addObjectCreate(fullPrefix + "/session-config", "org.apache.tomcat.util.descriptor.web.SessionConfig"); //解析到xx/session-config，调用WebXml的setSessionConfig，传入参数SessionConfig digester.addSetNext(fullPrefix + "/session-config", "setSessionConfig", "org.apache.tomcat.util.descriptor.web.SessionConfig"); //解析到xx/session-config/ session-timeout，调用SessionConfig的setSessionTimeout，参数是标签的body text digester.addCallMethod(fullPrefix + "/session-config/session-timeout", "setSessionTimeout", 0); //解析到xx/ session-config/cookie-config/name，调用SessionConfig的setCookieName，参数是标签的body text digester.addCallMethod(fullPrefix + "/session-config/cookie-config/name", "setCookieName", 0); //解析到xx/ session-config/cookie-config/ domain，调用SessionConfig的setCookieDomain，参数是标签的body text digester.addCallMethod(fullPrefix + "/session-config/cookie-config/domain", "setCookieDomain", 0); //解析到xx/ session-config/cookie-config/ path，调用SessionConfig的setCookiePath，参数是标签的body text digester.addCallMethod(fullPrefix + "/session-config/cookie-config/path", "setCookiePath", 0); //解析到xx/ session-config/cookie-config/ comment，调用SessionConfig的setCookieComment，参数是标签的body text digester.addCallMethod(fullPrefix + "/session-config/cookie-config/comment", "setCookieComment", 0); //解析到xx/ session-config/cookie-config/ http-only，调用SessionConfig的setCookieHttpOnly，参数是标签的body text digester.addCallMethod(fullPrefix + "/session-config/cookie-config/http-only", "setCookieHttpOnly", 0); //解析到xx/ session-config/cookie-config/ secure，调用SessionConfig的setCookieSecure，参数是标签的body text digester.addCallMethod(fullPrefix + "/session-config/cookie-config/secure", "setCookieSecure", 0); //解析到xx/ session-config/cookie-config/ max-age，调用SessionConfig的setCookieMaxAge，参数是标签的body text digester.addCallMethod(fullPrefix + "/session-config/cookie-config/max-age", "setCookieMaxAge", 0); //解析到xx/ session-config/cookie-config/ tracking-mode，调用SessionConfig的addSessionTrackingMode，参数是标签的body text digester.addCallMethod(fullPrefix + "/session-config/tracking-mode", "addSessionTrackingMode", 0); // Taglibs pre Servlet 2.4 //解析到xx/taglib，TaglibLocationRule rule参数false表示是pre Servlet 2.4， 2.4之前version的，WebXml必须有publicID digester.addRule(fullPrefix + "/taglib", new TaglibLocationRule(false)); //解析到xx/taglib结束标签，调用WebXml的addTaglib方法，传入参数是之前push进的parameters digester.addCallMethod(fullPrefix + "/taglib", "addTaglib", 2); //解析到xx/taglib/taglib-location，push进digester的parameters，参数是标签的body text，参数index是1 digester.addCallParam(fullPrefix + "/taglib/taglib-location", 1); //解析到xx/taglib/ taglib-uri，push进digester的parameters，参数是标签的body text，参数index是0 digester.addCallParam(fullPrefix + "/taglib/taglib-uri", 0); // Taglibs Servlet 2.4 onwards //解析到xx/jsp-config/taglib，TaglibLocationRule rule参数true，表示是2.4或者later的version，WebXml不能用public digester.addRule(fullPrefix + "/jsp-config/taglib", new TaglibLocationRule(true)); //解析到xx//jsp-config/taglib结束标签，调用WebXml的addTaglib方法，传入之前push进digester的参数 digester.addCallMethod(fullPrefix + "/jsp-config/taglib", "addTaglib", 2); //解析到xx/jsp-config/taglib/taglib-location，push进digester的parameters，作为第二个参数（标签的body text） digester.addCallParam(fullPrefix + "/jsp-config/taglib/taglib-location", 1); //解析到xx/jsp-config/taglib/ taglib-uri，push进digester的parameters，作为第一个参数（标签的body text） digester.addCallParam(fullPrefix + "/jsp-config/taglib/taglib-uri", 0); //解析到xx/ welcome-file-list/welcome-file的時候，调用WebXml的addWelcomeFile方法，参数是标签的body text digester.addCallMethod(fullPrefix + "/welcome-file-list/welcome-file", "addWelcomeFile", 0); //解析到xx/locale-encoding-mapping-list/locale-encoding-mapping结束标签，调用WebXml的addLocaleEncodingMapping，传入之前push进digester的paramters digester.addCallMethod(fullPrefix + "/locale-encoding-mapping-list/locale-encoding-mapping", "addLocaleEncodingMapping", 2); //解析到xx/locale-encoding-mapping-list/locale-encoding-mapping/locale，push进digester的parameters，作为第一个参数(body text) digester.addCallParam(fullPrefix + "/locale-encoding-mapping-list/locale-encoding-mapping/locale", 0); //解析到xx/locale-encoding-mapping-list/ locale-encoding-mapping/encoding，push进digester的parameters，作为第二个参数(body text) digester.addCallParam(fullPrefix + "/locale-encoding-mapping-list/locale-encoding-mapping/encoding", 1); //解析到xx/post-construct结束标签，LifecycleCallbackRule rule 不能有重复的class，调用WebXml的addPostConstructMethods，传入之前push进digester的parameters digester.addRule(fullPrefix + "/post-construct", new LifecycleCallbackRule("addPostConstructMethods", 2, true)); //解析到xx/ post-construct/lifecycle-callback-class，push进digester的paramters，做为第一个参数(body text) digester.addCallParam(fullPrefix + "/post-construct/lifecycle-callback-class", 0); //解析到xx/post-construct/ lifecycle-callback-method，push进digester的paramters，做为第二个参数(body text) digester.addCallParam(fullPrefix + "/post-construct/lifecycle-callback-method", 1); //解析到xx/pre-destroy结束标签，LifecycleCallbackRule rule 不能有重复的class，调用WebXml的addPreDestroyMethods，传入之前push进digester的parameters digester.addRule(fullPrefix + "/pre-destroy", new LifecycleCallbackRule("addPreDestroyMethods", 2, false)); //解析到xx/pre-destroy/lifecycle-callback-class，push进digester的paramters，做为第一个参数(body text) digester.addCallParam(fullPrefix + "/pre-destroy/lifecycle-callback-class", 0); //解析到xx/pre-destroy/ lifecycle-callback-method，push进digester的paramters，做为第二个参数(body text) digester.addCallParam(fullPrefix + "/pre-destroy/lifecycle-callback-method", 1); }
2. 分析解析WebXmlFragment：
代码片段
Set<WebXml> defaults = new HashSet<>();
defaults.add(getDefaultWebXmlFragment(webXmlParser));
这段代码执行完后，defaults里面有DefaultWebXml（conf/web.xml or host的web.xml.default）
方法getDefaultWebXmlFragment(WebXmlParser webXmlParser)：
private WebXml getDefaultWebXmlFragment(WebXmlParser webXmlParser) { //获得container，默认应该是StandardHost Host host = (Host) context.getParent(); //通过host来获得cache到的DefaultWebXml实例对象 DefaultWebXmlCacheEntry entry = hostWebXmlCache.get(host); //获得CatalianBase/config/Web.xml的InputSource InputSource globalWebXml = getGlobalWebXmlSource(); //获得CatalianBase/config/engine/hostname/web.xml.default的InputSource InputSource hostWebXml = getHostWebXmlSource(); long globalTimeStamp = 0; long hostTimeStamp = 0; //设置global和host的webxml文件LastModified if (globalWebXml != null) { URLConnection uc = null; try { URL url = new URL(globalWebXml.getSystemId()); uc = url.openConnection(); globalTimeStamp = uc.getLastModified(); } catch (IOException e) { globalTimeStamp = -1; } finally { if (uc != null) { try { uc.getInputStream().close(); } catch (IOException e) { ExceptionUtils.handleThrowable(e); globalTimeStamp = -1; } } } } if (hostWebXml != null) { URLConnection uc = null; try { URL url = new URL(hostWebXml.getSystemId()); uc = url.openConnection(); hostTimeStamp = uc.getLastModified(); } catch (IOException e) { hostTimeStamp = -1; } finally { if (uc != null) { try { uc.getInputStream().close(); } catch (IOException e) { ExceptionUtils.handleThrowable(e); hostTimeStamp = -1; } } } } //获取缓存的DefaultWebXml if (entry != null && entry.getGlobalTimeStamp() == globalTimeStamp && entry.getHostTimeStamp() == hostTimeStamp) { InputSourceUtil.close(globalWebXml); InputSourceUtil.close(hostWebXml); return entry.getWebXml(); } synchronized (host.getPipeline()) { entry = hostWebXmlCache.get(host); if (entry != null && entry.getGlobalTimeStamp() == globalTimeStamp && entry.getHostTimeStamp() == hostTimeStamp) { return entry.getWebXml(); } //创建WebXml WebXml webXmlDefaultFragment = createWebXml(); //设置为true，表示每个app的xml可以覆盖defaultwebxml相同的项 webXmlDefaultFragment.setOverridable(true); //设置Distributable为true，否则每个app就不会合并defaultwebxml webXmlDefaultFragment.setDistributable(true); //设置false，当merge defaultwebxml的时候，app未定义welcomefile文件时，才会合并默认的welcomefiles webXmlDefaultFragment.setAlwaysAddWelcomeFiles(false); if (globalWebXml == null) { log.info(sm.getString("contextConfig.defaultMissing")); } else { //用1分析的WebRuleSet rule，将globalWebXml 作为source，digester解析得到处理后的webXmlDefaultFragment（WebXml对象） if (!webXmlParser.parseWebXml( globalWebXml, webXmlDefaultFragment, false)) { ok = false; } } //替换当前的welcomefiles，当merge webxml到webXmlDefaultFragment时 webXmlDefaultFragment.setReplaceWelcomeFiles(true); //将hostWebXml作为source，digester解析得到处理后的webXmlDefaultFragment if (!webXmlParser.parseWebXml( hostWebXml, webXmlDefaultFragment, false)) { ok = false; } if (globalTimeStamp != -1 && hostTimeStamp != -1) { //设置Cache entry = new DefaultWebXmlCacheEntry(webXmlDefaultFragment, globalTimeStamp, hostTimeStamp); hostWebXmlCache.put(host, entry); } return webXmlDefaultFragment; } }
3. 分析解析ContextWebXml
代码片段：
//实例化一个全新的WebXml，不同于上面的defaultwebxml
WebXml webXml = createWebXml();
//获得context webxml的inputsource准备用digester来解析得到webxml
InputSource contextWebXml = getContextWebXmlSource();
//digester解析获得前面创建的WebXml
if (!webXmlParser.parseWebXml(contextWebXml, webXml, false)) {
ok = false;
}
getContextWebXmlSource()方法：
protected InputSource getContextWebXmlSource() { InputStream stream = null; InputSource source = null; URL url = null; String altDDName = null; // ServletContext会单独分析，现在只要知道它是一个app的上下文环境 ServletContext servletContext = context.getServletContext(); try { if (servletContext != null) { altDDName = (String)servletContext.getAttribute(Globals.ALT_DD_ATTR); if (altDDName != null) { // 有org.apache.catalina.deploy.alt_dd对应的value作为source try { stream = new FileInputStream(altDDName); url = new File(altDDName).toURI().toURL(); } catch (FileNotFoundException e) { log.error(sm.getString("contextConfig.altDDNotFound", altDDName)); } catch (MalformedURLException e) { log.error(sm.getString("contextConfig.applicationUrl")); } } else { //没有org.apache.catalina.deploy.alt_dd对应的value，则使用……/WEB-INF/web.xml作为source stream = servletContext.getResourceAsStream (Constants.ApplicationWebXml); try { url = servletContext.getResource( Constants.ApplicationWebXml); } catch (MalformedURLException e) { log.error(sm.getString("contextConfig.applicationUrl")); } } } if (stream == null || url == null) { if (log.isDebugEnabled()) { log.debug(sm.getString("contextConfig.applicationMissing") + " " + context); } } else { source = new InputSource(url.toExternalForm()); source.setByteStream(stream); } } …………………. return source; }
4.分析step1
代码片段：
Map<String,WebXml> fragments = processJarsForWebFragments(webXml, webXmlParser);
processJarsForWebFragments方法： protected Map<String,WebXml> processJarsForWebFragments(WebXml application, WebXmlParser webXmlParser) { //获得JarScanner默认是StandardJarScanner JarScanner jarScanner = context.getJarScanner(); boolean delegate = false; if (context instanceof StandardContext) { delegate = ((StandardContext) context).getDelegate(); } boolean parseRequired = true; Set<String> absoluteOrder = application.getAbsoluteOrdering(); if (absoluteOrder != null && absoluteOrder.isEmpty() && !context.getXmlValidation()) { parseRequired = false; } //StandardJarScanner扫描开始 FragmentJarScannerCallback callback = new FragmentJarScannerCallback(webXmlParser, delegate, parseRequired); jarScanner.scan(JarScanType.PLUGGABILITY, context.getServletContext(), callback); if (!callback.isOk()) { ok = false; } return callback.getFragments(); }
StandardJarScanner类scan方法：
a. 扫描app的WEB-INF/lib下的jar包，解析jar包里面的META-INF/web-fragment.xml，FragmentJarScannerCallback scan解析fragments.put(fragment.getName(),fragment)
b. 扫描app 的/WEB-INF/classes 下的META-INF，如果不为空，调用callback的scanWebInfClasses
c. 扫描context的classloader以及classloader继承链上的classloader的searchpath上的jar包，解析jar包里面的META-INF/web- fragment.xml，FragmentJarScannerCallback scan解析fragments.put(fragment.getName(),fragment)
5.分析step2
代码片段：
Set<WebXml> orderedFragments = null;
orderedFragments =
WebXml.orderWebFragments(webXml, fragments, sContext);
对WebXml进行排序
6.分析step3
代码片段：
if (ok) {
processServletContainerInitializers();
}
processServletContainerInitializers方法：
protected void processServletContainerInitializers() { List<ServletContainerInitializer> detectedScis; try { //app的classloader加载xxx/META-INF/services/ ServletContainerInitializer资源，读取资源里面的ServletContainerInitializer配置，以#分割，然后classloader反射实例化ServletContainerInitializer(detectedScis) // WebappServiceLoader类load方法 WebappServiceLoader<ServletContainerInitializer> loader = new WebappServiceLoader<>(context); detectedScis = loader.load(ServletContainerInitializer.class); } catch (IOException e) { log.error(sm.getString( "contextConfig.servletContainerInitializerFail", context.getName()), e); ok = false; return; } for (ServletContainerInitializer sci : detectedScis) { //填充initializerClassMap initializerClassMap.put(sci, new HashSet<Class<?>>()); HandlesTypes ht; try { //获得sci的HandlesTypes annotation ht = sci.getClass().getAnnotation(HandlesTypes.class); } catch (Exception e) { if (log.isDebugEnabled()) { log.info(sm.getString("contextConfig.sci.debug", sci.getClass().getName()), e); } else { log.info(sm.getString("contextConfig.sci.info", sci.getClass().getName())); } continue; } if (ht == null) { continue; } // HandlesTypes annotation配置的class[] Class<?>[] types = ht.value(); if (types == null) { continue; } //填充typeInitializerMap，key是class[]里面配置的type,value是ServletContainerInitializer对象 for (Class<?> type : types) { if (type.isAnnotation()) { handlesTypesAnnotations = true; } else { handlesTypesNonAnnotations = true; } Set<ServletContainerInitializer> scis = typeInitializerMap.get(type); if (scis == null) { scis = new HashSet<>(); typeInitializerMap.put(type, scis); } scis.add(sci); } } }
WebappServiceLoader类load方法
public List<T> load(Class<T> serviceType) throws IOException { String configFile = SERVICES + serviceType.getName(); LinkedHashSet<String> applicationServicesFound = new LinkedHashSet<>(); LinkedHashSet<String> containerServicesFound = new LinkedHashSet<>(); ClassLoader loader = servletContext.getClassLoader(); @SuppressWarnings("unchecked") List<String> orderedLibs = (List<String>) servletContext.getAttribute(ServletContext.ORDERED_LIBS); if (orderedLibs != null) { //如果配置了javax.servlet.context.orderedLibs key的value，迭代实例化applicationServicesFound，source是/WEB-INF/lib下的jar包里面的META-INF/services/ ServletContainerInitializer for (String lib : orderedLibs) { URL jarUrl = servletContext.getResource(LIB + lib); if (jarUrl == null) { // should not happen, just ignore continue; } String base = jarUrl.toExternalForm(); URL url; if (base.endsWith("/")) { url = new URL(base + configFile); } else { url = JarFactory.getJarEntryURL(jarUrl, configFile); } try { parseConfigFile(applicationServicesFound, url); } catch (FileNotFoundException e) { // no provider file found, this is OK } } loader = context.getParentClassLoader(); } //实例化containerServicesFound，source是META-INF/services/ ServletContainerInitializer Enumeration<URL> resources; if (loader == null) { resources = ClassLoader.getSystemResources(configFile); } else { resources = loader.getResources(configFile); } while (resources.hasMoreElements()) { parseConfigFile(containerServicesFound, resources.nextElement()); } //filter if (containerSciFilterPattern != null) { Iterator<String> iter = containerServicesFound.iterator(); while (iter.hasNext()) { if (containerSciFilterPattern.matcher(iter.next()).find()) { iter.remove(); } } } containerServicesFound.addAll(applicationServicesFound); if (containerServicesFound.isEmpty()) { return Collections.emptyList(); } //通过containerServicesFound读取到的ServletContainerInitializer配置信息，来实例化ServletContainerInitializer return loadServices(serviceType, containerServicesFound); }
7. 分析step4
代码片段：
if (!webXml.isMetadataComplete() || typeInitializerMap.size() > 0) {
//webXml的metadataComplete flase或者配置了ServletContainerInitializer相关的信息
Map<String,JavaClassCacheEntry> javaClassCache = new HashMap<>();
if (ok) {
WebResource[] webResources =
context.getResources().listResources("/WEB-INF/classes");
for (WebResource webResource : webResources) {
//循环迭代处理/WEB-INF/classes下的资源
if ("META-INF".equals(webResource.getName())) {
//不处理META-INF
continue;
}
processAnnotationsWebResource(webResource, webXml,
webXml.isMetadataComplete(), javaClassCache);
}
}
processAnnotationsWebResource方法：
protected void processAnnotationsWebResource(WebResource webResource, WebXml fragment, boolean handlesTypesOnly, Map<String,JavaClassCacheEntry> javaClassCache) { if (webResource.isDirectory()) { //如果webResource是目录，将递归调用processAnnotationsWebResource WebResource[] webResources = webResource.getWebResourceRoot().listResources( webResource.getWebappPath()); ……………….. for (WebResource r : webResources) { processAnnotationsWebResource(r, fragment, handlesTypesOnly, javaClassCache); } } } else if (webResource.isFile() && webResource.getName().endsWith(".class")) { //如果是file并且是class文件，调用processAnnotationsStream try (InputStream is = webResource.getInputStream()) { processAnnotationsStream(is, fragment, handlesTypesOnly, javaClassCache); } catch (IOException e) { log.error(sm.getString("contextConfig.inputStreamWebResource", webResource.getWebappPath()),e); } catch (ClassFormatException e) { log.error(sm.getString("contextConfig.inputStreamWebResource", webResource.getWebappPath()),e); } } } 看processAnnotationsStream源码片段 protected void processAnnotationsStream(InputStream is, WebXml fragment, boolean handlesTypesOnly, Map<String,JavaClassCacheEntry> javaClassCache) throws ClassFormatException, IOException { ………….. String className = clazz.getClassName(); for (AnnotationEntry ae : annotationsEntries) { String type = ae.getAnnotationType(); if ("Ljavax/servlet/annotation/WebServlet;".equals(type)) { processAnnotationWebServlet(className, ae, fragment); }else if ("Ljavax/servlet/annotation/WebFilter;".equals(type)) { processAnnotationWebFilter(className, ae, fragment); }else if ("Ljavax/servlet/annotation/WebListener;".equals(type)) { fragment.addListener(className); } else { // Unknown annotation - ignore } } } }
最后会根据注解不同，调用不同的方法
WebServlet--------------à processAnnotationWebServlet
WebFilter----------------à processAnnotationWebFilter
WebListener------------à fragment.addListener
processAnnotationWebServlet 方法：
解析WebServlet注解相关信息，创建ServletDef对象，将相关属性设置进ServletDef，最后add进webXml的servletDefs 相关代码片段
for (ElementValuePair evp : evps) {
String name = evp.getNameString();
if ("value".equals(name) || "urlPatterns".equals(name)) {
if (urlPatternsSet) {
throw new IllegalArgumentException(sm.getString(
"contextConfig.urlPatternValue", "WebServlet", className));
}
urlPatternsSet = true;
urlPatterns = processAnnotationsStringArray(evp.getValue());
} else if ("description".equals(name)) {
if (servletDef.getDescription() == null) {
servletDef.setDescription(evp.getValue().stringifyValue());
}
} else if ("displayName".equals(name)) {
if (servletDef.getDisplayName() == null) {
servletDef.setDisplayName(evp.getValue().stringifyValue());
}
} else if ("largeIcon".equals(name)) {
if (servletDef.getLargeIcon() == null) {
servletDef.setLargeIcon(evp.getValue().stringifyValue());
}
} else if ("smallIcon".equals(name)) {
if (servletDef.getSmallIcon() == null) {
servletDef.setSmallIcon(evp.getValue().stringifyValue());
}
} else if ("asyncSupported".equals(name)) {
if (servletDef.getAsyncSupported() == null) {
servletDef.setAsyncSupported(evp.getValue()
.stringifyValue());
}
} else if ("loadOnStartup".equals(name)) {
…………….
} else if ("initParams".equals(name)) {
………………
}
}
}
processAnnotationWebFilter方法：
跟processAnnotationWebServlet方法类似，不过是filterDef
调用fragment.addListener方法：
WebXml的addListener方法
public void addListener(String className) {
listeners.add(className);
}
8. 分析step5
代码片段：
if (!webXml.isMetadataComplete() || typeInitializerMap.size() > 0) {
//st ep4……
//step5跟step4类似，都是要解析class上的注解，@WebServlet，@WebFilter，@WebListener，不同于step4，step5解析的是step1步骤下解析的webfragment
if (ok) {
processAnnotations(
orderedFragments, webXml.isMetadataComplete(), javaClassCache);
}
// Cache, if used, is no longer required so clear it
javaClassCache.clear();
}
9.分析step6~9
代码片段：
if (!webXml.isMetadataComplete()) {
// Step 6. Merge web-fragment.xml files into the main web.xml
// file.
//将前面分析的主webxml与step1解析得到的webxml merge，具体逻辑可以以后再看
if (ok) {
ok = webXml.merge(orderedFragments);
}
// Step 7. Apply global defaults
// Have to merge defaults before JSP conversion since defaults
// provide JSP servlet definition
//将前面分析的主webxml与前面分析的defaults webxml，具体逻辑可以以后再看.
webXml.merge(defaults);
// Step 8. Convert explicitly mentioned jsps to servlets
if (ok) {
//主要是设置org.apache.jasper.servlet.JspServlet的ServletDef
convertJsps(webXml);
}
// Step 9. Apply merged web.xml to Context
if (ok) {
//将webXml存储的某些配置信息传递给当前的StandardContext
configureContext(webXml);
}
} else {
webXml.merge(defaults);
convertJsps(webXml);
configureContext(webXml);
}
10.分析step10
代码片段：
if (ok) {
//解析WEB-INF/classes/META-INF/下的静态资源，以后可以分析，静态分析跟WebResourceRoot和WebResource类有关
// Spec does not define an order.
// Use ordered JARs followed by remaining JARs
Set<WebXml> resourceJars = new LinkedHashSet<>();
for (WebXml fragment : orderedFragments) {
resourceJars.add(fragment);
}
for (WebXml fragment : fragments.values()) {
if (!resourceJars.contains(fragment)) {
resourceJars.add(fragment);
}
}
processResourceJARs(resourceJars);
// See also StandardContext.resourcesStart() for
// WEB-INF/classes/META-INF/resources configuration
}
11.分析step11
代码片段：将webxml的ServletContainerInitializer同步进context，initializerClassMap是在checkHandlesTypes方法填充，xxx/WEB-INF/classes下的资源
if (ok) {
for (Map.Entry<ServletContainerInitializer,
Set<Class<?>>> entry :
initializerClassMap.entrySet()) {
if (entry.getValue().isEmpty()) {
context.addServletContainerInitializer(
entry.getKey(), null);
} else {
context.addServletContainerInitializer(
entry.getKey(), entry.getValue());
}
}
}
总结：这个是初步的分析，随着以后整个流程的走通，再去分析最后涉及到的细节，ConfigureStart方法是在beforeStart之后和start之前触发， StandardContext的startInternal方法就可以用到ConfigureStart方法中解析得到的信息，webconfig方法，就如它的名字，读取tomcat的webxml的配置，将defaultweb(config/webxml)或者host默认的webxml合并到当前app的主webxml，读取META-INF和 WEB-INF下的配置，比如ServletContainerInitializer，注解@WebServlet，@WebFilter，@WebListener等信息来填充WebXml（ServletDef，FilterDef etc.），最后将WebXml的信息设置给当前的StandardContext以供后面使用
