[转] Struts2 使用 Interceptor 拦截 jsp 页面

From：http://www.iteye.com/topic/264249

 

由于Struts2 的是基于 Filter 的拦截机制实现的。所以，使用 Struts2 的 Interceptor 解析请求进行处理即可实现拦截 jsp 页面需求

代码转载：

import javax.servlet.http.HttpServletRequest;

import org.apache.struts2.ServletActionContext;

import com.javasystem.JavaSystemConstants;
import com.javasystem.action.TuserCRUDAction;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.AbstractInterceptor;

public class LoginInterceptor extends AbstractInterceptor {

    private static final long serialVersionUID = 8760120133840824493L;
    public static final String LOGIN_KEY = "LOGIN";
    // find <result name="global.login"
    // type="redirect">sysLogout.action</result> is the forward action .
    public static final String LOGIN_PAGE = "global.login";

    @Override
    public String intercept(ActionInvocation actionInvocation) throws Exception {
        System.out.println("begin check login interceptor!");
        // don't check user login action itself .
        Object action = actionInvocation.getAction();
        if (action instanceof TuserCRUDAction) {
            System.out
                    .println("exit check login, because this is login action.");
            return actionInvocation.invoke();
        }
        // check user login session .
        ActionContext ctx = ActionContext.getContext();
        HttpServletRequest request = (HttpServletRequest) ctx
                .get(ServletActionContext.HTTP_REQUEST);
        Object userSession = request.getSession().getAttribute(
                JavaSystemConstants.USER_LOGIN_SESSION_NAME);
        // get session use session name .
        if (userSession != null) {
            //  
            System.out.println("already login!");
            return actionInvocation.invoke();
        } else {
            //  
            System.out.println("no login, forward login page!");
            return LOGIN_PAGE;

        }

    }

}

这个地方可以获得的到request了就可以得到一个url。。。

<package name="javasys" extends="struts-default">
        <interceptors>
            <interceptor-stack name="authenticationStack">
                <interceptor-ref name="fileUpload">
                    <param name="maximumSize">1024000000</param>
                </interceptor-ref>
                <interceptor-ref name="basicStack" />
            </interceptor-stack>
            <interceptor name="login"
                class="com.javasystem.core.interceptor.LoginInterceptor" />
            <interceptor-stack name="teamwareStack">
                <interceptor-ref name="i18n" />
                <interceptor-ref name="login" />
                <interceptor-ref name="basicStack" />
            </interceptor-stack>
        </interceptors>
    ..........

在下面配置下默认的拦截器就好了。