struts2.0拦截器的用法

struts2.0拦截器的用法：

配置文件：

<package name="default" extends="struts-default">

        <interceptors>
         <!-- 定义拦截器 loginInterceptor 继承default的package中action都可以引用该拦截器-->
            <interceptor name="loginInterceptor" class="com.cetc.util.CheckLoginInterceptor" />
            <!-- 定义拦截器堆栈 loginInterceptorStack -->
            <interceptor-stack name="loginInterceptorStack">
             <!-- 引用默认拦截器 defaultStack -->
                <interceptor-ref name="defaultStack" />
                <!-- 引用自定义拦截器 loginInterceptor -->
                <interceptor-ref name="loginInterceptor" />
            </interceptor-stack>
        </interceptors>
      
       
        <!-- 重定义默认拦截器堆栈 这里不要使用，若定义后凡是继承了default的package都回执行该拦截器-->
     <!--<default-interceptor-ref name="loginInterceptorStack"/>-->
    
       
    </package>



<package name="login" extends="default">
        <action name="login" class="com.cetc.struts.action.t00hy.LoginAction" method="login">
            <result name="input">/pages/home/login.jsp</result>
            <result name="to_zbr">/pages/t02qy/util/index_zbr.jsp</result>
            <result name="to_tbr">/pages/t02qy/util/index_tbr.jsp</result>
            <result name="to_zj">/pages/t01zj/util/index_zj.jsp</result>
            <result name="to_admin">/pages/home/index_admin.jsp</result>
            <!-- 引用拦截器 loginInterceptorStack -->
            <interceptor-ref name="loginInterceptorStack"></interceptor-ref>
        </action>
        <action name="qyLogin" class="com.cetc.struts.action.t00hy.LoginAction" method="qyLogin">
            <result name="input">/pages/home/login.jsp</result>
            <result name="to_zbr">/pages/t02qy/util/index_zbr.jsp</result>
            <result name="to_tbr">/pages/t02qy/util/index_tbr.jsp</result>
            <result name="to_zj">/pages/t01zj/util/index_zj.jsp</result>
            <result name="to_admin">/pages/home/index_admin.jsp</result>
            <!-- 引用拦截器 loginInterceptorStack -->
            <interceptor-ref name="loginInterceptorStack"></interceptor-ref>
        </action>
  <action name="logout" class="com.cetc.struts.action.t00hy.LoginAction" method="logout">
            <result name="success">/pages/home/login.jsp</result>
        </action>
  <action name="goLogin" class="com.cetc.struts.action.t00hy.LoginAction" method="goLogin">
            <result name="success">/pages/home/login.jsp</result>
        </action>
    </package>
   


<package name="t00hy" namespace="/t00hy" extends="default">
  <action name="updateTWzHyzh" class="com.cetc.struts.action.t00hy.TWzHyzhAction" method="updateTWzHyzh">
   <result name="success" type="dispatcher">/pages/home/modifySuccess.jsp</result>
   <result name="input" type="dispatcher">/pages/home/modify_password.jsp</result>
            <!-- 引用拦截器 loginInterceptorStack -->
            <interceptor-ref name="loginInterceptorStack"></interceptor-ref>
  </action>
  <action name="goModifyPassword" class="com.cetc.struts.action.t00hy.TWzHyzhAction" method="goModifyPassword">
   <result name="success" type="dispatcher">/pages/home/modify_password.jsp</result>
            <!-- 引用拦截器 loginInterceptorStack -->
            <interceptor-ref name="loginInterceptorStack"></interceptor-ref>
  </action>

</package>



抽象类：


import com.opensymphony.xwork2.interceptor.Interceptor;
import com.opensymphony.xwork2.ActionInvocation;


public abstract class AbstractInterceptor implements Interceptor {

public void destroy() {
  // TODO Auto-generated method stub
  System.out.println("LoginInterceptor.destroy()!");
}

public void init() {
  // TODO Auto-generated method stub
  System.out.println("LoginInterceptor.init()!");
}

public abstract String intercept(ActionInvocation invocation) throws Exception;
  // TODO Auto-generated method stub

}


自定义拦截器：


import java.util.Map;

import com.cetc.struts.action.t00hy.LoginAction;
import com.opensymphony.xwork2.ActionInvocation;

public class CheckLoginInterceptor extends AbstractInterceptor {

private static final long serialVersionUID = -8624767071049356602L;
public static final String LOGIN_KEY = "LOGINED";
    public static final String LOGIN_PAGE = "login";

    public String intercept(ActionInvocation actionInvocation) throws Exception {

        System.out.println("begin check login interceptor!");
        // 对LoginAction不做该项拦截
        Object action = actionInvocation.getAction();
        if (action instanceof LoginAction) {
            System.out.println("exit check login, because this is login action.");
            return actionInvocation.invoke();
        }

        // 确认Session中是否存在LOGIN
        Map session = actionInvocation.getInvocationContext().getSession();
        String login = (String) session.get(LOGIN_KEY);
        if (login != null && login.length() > 0) {
            // 存在的情况下进行后续操作。
            System.out.println("already login!");
            return actionInvocation.invoke();
        }else{
            // 否则终止后续操作，返回LOGIN
            System.out.println("no login, forward login page!");
            return LOGIN_PAGE;
        }
    }


}