１）预定义拦截器
Struts2有默认的拦截器配置，也就是说，虽然我们没有主动去配置任何关于拦截器的东西，但是Struts2会使用默认引用的拦截器。由于Struts2的默认拦截器声明和引用都在这个Struts-default.xml里面，因此我们需要到这个文件的struts-default包里去看一下。定义如下：
1 <interceptors> 2 <interceptor name="alias" class="com.opensymphony.xwork2.interceptor.AliasInterceptor"/> 3 <interceptor name="autowiring" class="com.opensymphony.xwork2.spring.interceptor.ActionAutowiringInterceptor"/> 4 <interceptor name="chain" class="com.opensymphony.xwork2.interceptor.ChainingInterceptor"/> 5 <interceptor name="conversionError" class="org.apache.struts2.interceptor.StrutsConversionErrorInterceptor"/> 6 <interceptor name="cookie" class="org.apache.struts2.interceptor.CookieInterceptor"/> 7 <interceptor name="cookieProvider" class="org.apache.struts2.interceptor.CookieProviderInterceptor"/> 8 <interceptor name="clearSession" class="org.apache.struts2.interceptor.ClearSessionInterceptor" /> 9 <interceptor name="createSession" class="org.apache.struts2.interceptor.CreateSessionInterceptor" /> 10 <interceptor name="debugging" class="org.apache.struts2.interceptor.debugging.DebuggingInterceptor" /> 11 <interceptor name="execAndWait" class="org.apache.struts2.interceptor.ExecuteAndWaitInterceptor"/> 12 <interceptor name="exception" class="com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor"/> 13 <interceptor name="fileUpload" class="org.apache.struts2.interceptor.FileUploadInterceptor"/> 14 <interceptor name="i18n" class="com.opensymphony.xwork2.interceptor.I18nInterceptor"/> 15 <interceptor name="logger" class="com.opensymphony.xwork2.interceptor.LoggingInterceptor"/> 16 <interceptor name="modelDriven" class="com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor"/> 17 <interceptor name="scopedModelDriven" class="com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor"/> 18 <interceptor name="params" class="com.opensymphony.xwork2.interceptor.ParametersInterceptor"/> 19 <interceptor name="actionMappingParams" class="org.apache.struts2.interceptor.ActionMappingParametersInteceptor"/> 20 <interceptor name="prepare" class="com.opensymphony.xwork2.interceptor.PrepareInterceptor"/> 21 <interceptor name="staticParams" class="com.opensymphony.xwork2.interceptor.StaticParametersInterceptor"/> 22 <interceptor name="scope" class="org.apache.struts2.interceptor.ScopeInterceptor"/> 23 <interceptor name="servletConfig" class="org.apache.struts2.interceptor.ServletConfigInterceptor"/> 24 <interceptor name="timer" class="com.opensymphony.xwork2.interceptor.TimerInterceptor"/> 25 <interceptor name="token" class="org.apache.struts2.interceptor.TokenInterceptor"/> 26 <interceptor name="tokenSession" class="org.apache.struts2.interceptor.TokenSessionStoreInterceptor"/> 27 <interceptor name="validation" class="org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor"/> 28 <interceptor name="workflow" class="com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor"/> 29 <interceptor name="store" class="org.apache.struts2.interceptor.MessageStoreInterceptor" /> 30 <interceptor name="checkbox" class="org.apache.struts2.interceptor.CheckboxInterceptor" /> 31 <interceptor name="profiling" class="org.apache.struts2.interceptor.ProfilingActivationInterceptor" /> 32 <interceptor name="roles" class="org.apache.struts2.interceptor.RolesInterceptor" /> 33 <interceptor name="annotationWorkflow" class="com.opensymphony.xwork2.interceptor.annotations.AnnotationWorkflowInterceptor" /> 34 <interceptor name="multiselect" class="org.apache.struts2.interceptor.MultiselectInterceptor" /> 35 <interceptor name="deprecation" class="org.apache.struts2.interceptor.DeprecationInterceptor" /> 36 37 <!-- Basic stack --> 38 <interceptor-stack name="basicStack"> 39 <interceptor-ref name="exception"/> 40 <interceptor-ref name="servletConfig"/> 41 <interceptor-ref name="prepare"/> 42 <interceptor-ref name="checkbox"/> 43 <interceptor-ref name="multiselect"/> 44 <interceptor-ref name="actionMappingParams"/> 45 <interceptor-ref name="params"> 46 <param name="excludeParams">^class\..*,^dojo\..*,^struts\..*,^session\..*,^request\..*,^application\..*,^servlet(Request|Response)\..*,^parameters\..*,^action:.*,^method:.*</param> 47 </interceptor-ref> 48 <interceptor-ref name="conversionError"/> 49 <interceptor-ref name="deprecation"/> 50 </interceptor-stack> 51 52 <!-- Sample validation and workflow stack --> 53 <interceptor-stack name="validationWorkflowStack"> 54 <interceptor-ref name="basicStack"/> 55 <interceptor-ref name="validation"/> 56 <interceptor-ref name="workflow"/> 57 </interceptor-stack> 58 59 <!-- Sample file upload stack --> 60 <interceptor-stack name="fileUploadStack"> 61 <interceptor-ref name="fileUpload"/> 62 <interceptor-ref name="basicStack"/> 63 </interceptor-stack> 64 65 <!-- Sample model-driven stack --> 66 <interceptor-stack name="modelDrivenStack"> 67 <interceptor-ref name="modelDriven"/> 68 <interceptor-ref name="basicStack"/> 69 </interceptor-stack> 70 71 <!-- Sample action chaining stack --> 72 <interceptor-stack name="chainStack"> 73 <interceptor-ref name="chain"/> 74 <interceptor-ref name="basicStack"/> 75 </interceptor-stack> 76 77 <!-- Sample i18n stack --> 78 <interceptor-stack name="i18nStack"> 79 <interceptor-ref name="i18n"/> 80 <interceptor-ref name="basicStack"/> 81 </interceptor-stack> 82 83 <!-- An example of the paramsPrepareParams trick. This stack 84 is exactly the same as the defaultStack, except that it 85 includes one extra interceptor before the prepare interceptor: 86 the params interceptor. 87 88 This is useful for when you wish to apply parameters directly 89 to an object that you wish to load externally (such as a DAO 90 or database or service layer), but can't load that object 91 until at least the ID parameter has been loaded. By loading 92 the parameters twice, you can retrieve the object in the 93 prepare() method, allowing the second params interceptor to 94 apply the values on the object. --> 95 <interceptor-stack name="paramsPrepareParamsStack"> 96 <interceptor-ref name="exception"/> 97 <interceptor-ref name="alias"/> 98 <interceptor-ref name="i18n"/> 99 <interceptor-ref name="checkbox"/> 100 <interceptor-ref name="multiselect"/> 101 <interceptor-ref name="params"> 102 <param name="excludeParams">^class\..*,^dojo\..*,^struts\..*,^session\..*,^request\..*,^application\..*,^servlet(Request|Response)\..*,^parameters\..*,^action:.*,^method:.*</param> 103 </interceptor-ref> 104 <interceptor-ref name="servletConfig"/> 105 <interceptor-ref name="prepare"/> 106 <interceptor-ref name="chain"/> 107 <interceptor-ref name="modelDriven"/> 108 <interceptor-ref name="fileUpload"/> 109 <interceptor-ref name="staticParams"/> 110 <interceptor-ref name="actionMappingParams"/> 111 <interceptor-ref name="params"> 112 <param name="excludeParams">^class\..*,^dojo\..*,^struts\..*,^session\..*,^request\..*,^application\..*,^servlet(Request|Response)\..*,^parameters\..*,^action:.*,^method:.*</param> 113 </interceptor-ref> 114 <interceptor-ref name="conversionError"/> 115 <interceptor-ref name="validation"> 116 <param name="excludeMethods">input,back,cancel,browse</param> 117 </interceptor-ref> 118 <interceptor-ref name="workflow"> 119 <param name="excludeMethods">input,back,cancel,browse</param> 120 </interceptor-ref> 121 </interceptor-stack> 122 123 <!-- A complete stack with all the common interceptors in place. 124 Generally, this stack should be the one you use, though it 125 may do more than you need. Also, the ordering can be 126 switched around (ex: if you wish to have your servlet-related 127 objects applied before prepare() is called, you'd need to move 128 servletConfig interceptor up. 129 130 This stack also excludes from the normal validation and workflow 131 the method names input, back, and cancel. These typically are 132 associated with requests that should not be validated. 133 --> 134 <interceptor-stack name="defaultStack"> 135 <interceptor-ref name="exception"/> 136 <interceptor-ref name="alias"/> 137 <interceptor-ref name="servletConfig"/> 138 <interceptor-ref name="i18n"/> 139 <interceptor-ref name="prepare"/> 140 <interceptor-ref name="chain"/> 141 <interceptor-ref name="scopedModelDriven"/> 142 <interceptor-ref name="modelDriven"/> 143 <interceptor-ref name="fileUpload"/> 144 <interceptor-ref name="checkbox"/> 145 <interceptor-ref name="multiselect"/> 146 <interceptor-ref name="staticParams"/> 147 <interceptor-ref name="actionMappingParams"/> 148 <interceptor-ref name="params"> 149 <param name="excludeParams">^class\..*,^dojo\..*,^struts\..*,^session\..*,^request\..*,^application\..*,^servlet(Request|Response)\..*,^parameters\..*,^action:.*,^method:.*</param> 150 </interceptor-ref> 151 <interceptor-ref name="conversionError"/> 152 <interceptor-ref name="validation"> 153 <param name="excludeMethods">input,back,cancel,browse</param> 154 </interceptor-ref> 155 <interceptor-ref name="workflow"> 156 <param name="excludeMethods">input,back,cancel,browse</param> 157 </interceptor-ref> 158 <interceptor-ref name="debugging"/> 159 <interceptor-ref name="deprecation"/> 160 </interceptor-stack> 161 162 <!-- The completeStack is here for backwards compatibility for 163 applications that still refer to the defaultStack by the 164 old name --> 165 <interceptor-stack name="completeStack"> 166 <interceptor-ref name="defaultStack"/> 167 </interceptor-stack> 168 169 <!-- Sample execute and wait stack. 170 Note: execAndWait should always be the *last* interceptor. --> 171 <interceptor-stack name="executeAndWaitStack"> 172 <interceptor-ref name="execAndWait"> 173 <param name="excludeMethods">input,back,cancel</param> 174 </interceptor-ref> 175 <interceptor-ref name="defaultStack"/> 176 <interceptor-ref name="execAndWait"> 177 <param name="excludeMethods">input,back,cancel</param> 178 </interceptor-ref> 179 </interceptor-stack> 180 181 </interceptors> 182 183 <default-interceptor-ref name="defaultStack"/>