struts2拦截器的使用

1.编写拦截器

　　自定义一个实现interceptor接口的类，或者继承AbstractInterceptor的类；

　　

public class MyInterceptor implements Interceptor {

private String hello;

public void destroy() {
   System.out.println("destroy============");
}

public void init() {
   System.out.println("init============");
   System.out.println("hello=================");

}

public String intercept(ActionInvocation invocation) throws Exception {
   System.out.println("intercept1============");
   String result = invocation.invoke();
   return result;
}

public String getHello() {
   return hello;
}

public void setHello(String hello) {
   this.hello = hello;
}

}

2.在struts.xml的package中注册上一步的拦截器

<!-- 拦截器配置 -->
    <interceptors>
     <interceptor name="myInterceptor" class="com.test.interceptor.MyInterceptor">
      <param name="hello">nihao</param>
     </interceptor>
     <interceptor name="myInterceptor2" class="com.test.interceptor.MyInterceptor2"></interceptor>
     <interceptor name="myInterceptor3" class="com.test.interceptor.MyInterceptor3"></interceptor>
   
    <!-- 拦截器栈配置,拦截栈可以包含拦截器栈 -->
     <interceptor-stack name="myStack">
     <interceptor-ref name="myInterceptor"></interceptor-ref>
     <interceptor-ref name="myInterceptor2"></interceptor-ref>
     <interceptor-ref name="defaultStack"></interceptor-ref>
    </interceptor-stack>
    </interceptors>
   
    <!-- 将自定义拦截器设置为默认拦截器-->
   
    <default-interceptor-ref name="myStack"></default-interceptor-ref>

 

3.在需要使用的action中引用上述拦截器    
 

<action name="login" class="com.struct2.test.LoginAction">
     <result name = "input">/login2.jsp</result>
     <result name = "login" type ="redirect">/login.jsp</result>
     <result name = "success">/result.jsp</result>
     <result name = "invalid.token">/login2.jsp</result>
     <!-- 防止表单重复提交的拦截器 -->
     <interceptor-ref name="token"></interceptor-ref>
    
      <!-- 指定/排除某些方法的拦截器,指定和排除同时存在时,指定的优先级高-->
    
     <interceptor-ref name="myInterceptor3">
      <param name="includeMethods">execute,test</param>
      <param name="excludeMethods">execute,test</param>
     </interceptor-ref>
   
      <!-- 当提供自定义的拦截器后,默认拦截器失效,所以要手动包含进来-->
    
     <interceptor-ref name="defaultStack"></interceptor-ref>
     </action>