struts2不能通过ONGL方式取出request中的Atrribute

请看下面一个很简单的Action

package com.ahgw.main.action;



import org.springframework.stereotype.Controller;



/**

 * Created with IntelliJ IDEA.

 * User: HYY

 * Date: 13-11-19

 * Time: 下午7:08

 * To change this template use File | Settings | File Templates.

 */

@Controller

public class Test2Action {

    private String hyy;

    

    public String execute() {

        System.out.println("hyy = " + hyy);

        return "success";

    }



    public String getHyy() {

        return hyy;

    }



    public void setHyy(String hyy) {

        this.hyy = hyy;

    }

}

 一般来说，如果request有hyy这个parameter，那么可以获取该值。然后如果request中仅有key为hyy的Atrribute，那么这一段代码是获取不了该值的。

请继续看：

public class TestInterceptor extends AbstractInterceptor {



    @Override

    public String intercept(ActionInvocation actionInvocation) throws Exception {

        HttpServletRequest request = (HttpServletRequest) actionInvocation.getInvocationContext().get(ServletActionContext.HTTP_REQUEST);

        request.setAttribute("hyy", "heyiyong");

        System.out.println("经过测试拦截器");

        return actionInvocation.invoke();

    }

}

        <interceptors>

            <interceptor name="testInterceptor" class="com.ahgw.admin.interceptor.TestInterceptor"></interceptor>

        </interceptors>




        <action name="test2Action" class="test2Action">

            <interceptor-ref name="testInterceptor"></interceptor-ref>

            <result>/test.jsp</result>

        </action>

了解清楚后，在浏览器输入/test2Action.do发现输出如下：

经过测试拦截器
hyy = null

 

总结：在struts2的action中，通过OGNL方式不能获取atrribute而只能获取到parameter的值。