Struts 2 mapping interceptors to action

最新推荐文章于 2022-04-24 13:50:01 发布

转载最新推荐文章于 2022-04-24 13:50:01 发布 · 275 阅读

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本文介绍了Struts2中如何通过配置文件定义拦截器，并将其应用于特定的动作(Action)上。通常，开发者会将动作归类到继承自struts-default的包中，该包包含了默认的一组拦截器。此外，还说明了如何使用interceptor-ref元素来为动作指定额外的拦截器。

Struts 2 developers are used to declare the actions belong to a package that extend the “struts-default“, which contains the default set of interceptors.

<package name="default" namespace="/" extends="struts-default">
    <action name="testingAction" 
        class="com.mkyong.common.action.TestingAction" >
        <result name="success">pages/result.jsp</result>
    </action>
</package>

The default set of interceptors are grouped as “defaultStack” in struts-default.xml file, which is located in the struts2-core.jar file. The “defaultStack” provides all the core Struts 2 functionality, which is suit the need of most application.

Mapping interceptor to action

To map other interceptors to action, use the “interceptor-ref” element.

<package name="default" namespace="/" extends="struts-default">
    <action name="testingAction" 
        class="com.mkyong.common.action.TestingAction" >
        <interceptor-ref name="timer"/>
        <interceptor-ref name="logger"/>
        <result name="success">pages/result.jsp</result>
    </action>
</package>

In above snippet code, it map the “timer” and “logger” interceptors to the “TestingAction” action class via “interceptor-ref” element.

The interceptors will fire in the order they’re declared.
Since the “TestingAction” is declared it’s own interceptors, it’s immediate loses all the inherit default set of interceptors, you must explicitly declare the “defaultStack” in order to use it, see below example.

<package name="default" namespace="/" extends="struts-default">
    <action name="testingAction" 
        class="com.mkyong.common.action.TestingAction" >
        <interceptor-ref name="timer"/>
        <interceptor-ref name="logger"/>
        <interceptor-ref name="defaultStack"/>
        <result name="success">pages/result.jsp</result>
    </action>
</package>