struts2拦截器介绍

从官网上摘了两个struts2拦截器的配置方法，自己就记录下来了：

第一种方式：配置单个拦截器

<package name="default" namespace="/system/login" extends="struts-default">   <interceptors>       <interceptor name="timer" class="com.zyujie.common.TimerInterceptor"/>       <interceptor name="logger" class="com.zyujie.common.LoggerInterceptor"/>   </interceptors>   <action name="login" class="userLogin" method="login">        <interceptor-ref name="timer"/>        <interceptor-ref name="logger"/>        <result name="input">login.jsp</result>        <result name="success" type="redirectAction">/secure/home</result>   </action></package>

第二种方式：通过拦截栈来配置拦截器

<package name="default" namespace="/system/login" extends="struts-default">   <interceptors>        <interceptor name="timer" class="com.zyujie.common.TimerInterceptor"/>        <interceptor name="logger" class="com.zyujie.common.LoggerInterceptor"/>        <interceptor-stack name="myStack">           <interceptor-ref name="timer"/>           <interceptor-ref name="logger"/>        </interceptor-stack>    </interceptors>    <action name="login" class="userLogin" method="login">         <interceptor-ref name="myStack"/>         <result name="input">login.jsp</result>         <result name="success" type="redirectAction">/secure/home</result>    </action></package>

第三种方式：是引用struts2默认为我们实现的拦截器

<package name="upload" namespace="/system/upload" extends="struts-default">    <action name="fileUploadOther" class="myFileUploadAction" method="fileUploadOther">        <!-- 动态设置savePath的属性值，设置为服务器上的路径 -->        <param name="savePath">D:\webapp\apache-tomcat-6.0.10\webapps\struts2upload\upfiles</param>        <param name="fileOpFileName">abcde.xls</param>        <result name="success" type="redirect">/ok.jsp</result>        <result name="input" type="redirect">/index.jsp</result>        <!-- 实现struts的默认拦截器功能，所以要在后面加一个defaultStack，默认拦截栈 -->        <interceptor-ref name="fileUpload">       <!-- 文件过滤 -->        <param name="allowedTypes">image/bmp,image/png,image/gif,image/jpeg,image/jpg</param>            <!-- 文件大小, 以字节为单位 -->        <param name="maximumSize">2097152</param>        </interceptor-ref>        <!-- 默认拦截器必须放在fileUpload之后，否则无效 -->        <interceptor-ref name="defaultStack" />    </action>        </package>

下面是自己写的两个拦截类：

public class LoggerInterceptor extends AbstractInterceptor {@Overridepublic String intercept(ActionInvocation invocation) throws Exception {Map map = invocation.getInvocationContext().getSession();if(map.get("userId") == null){/**用户没有登录**/System.out.println("没有session，重新登录。");}else{System.out.println("已有session，不用再次登录。");}return invocation.invoke();}}

 

public class TimerInterceptor extends AbstractInterceptor {@Overridepublic String intercept(ActionInvocation invocation) throws Exception {Map map = invocation.getInvocationContext().getSession();if(map.get("userId") == null){/**用户没有登录**/return Action.INPUT;}else{return invocation.invoke();}}}