struts2 之 攔截器

Struts2規定使用者自定義攔截器必須實作com.opensymphony.xwork2.interceptor.Interceptor接口

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

public class PermissionInterceptor implements Interceptor {

	@Override
	public void destroy() {

	}

	@Override
	public void init() {

	}

	@Override
	public String intercept(ActionInvocation invocation) throws Exception {
		Object user=ActionContext.getContext().getSession().get("user");
		if(user!=null) 
			return invocation.invoke();//過濾成功則繼續執行action中result
		ActionContext.getContext().put("message", "你沒有權限執行該操作！");
		return "success";//不成功則執行另一個視圖
	}

}
           

配置Struts2攔截器

Struts2攔截器需要在struts.xml中聲明，如下struts.xml配置檔案

<package name="employee" namespace="/control/employee" extends="struts-default">
		<interceptors>
			<interceptor name="permission" class="cn.ljf.PermissionInterceptor"></interceptor>
			<interceptor-stack name="permissionStack"> <!-- 攔截器棧 -->
				<interceptor-ref name="defaultStack"></interceptor-ref> <!-- 使用了自定義的攔截器，預設的将失效 -->	
				<interceptor-ref name="permission"></interceptor-ref>
			</interceptor-stack>
		</interceptors>
		
		<global-results>
			<result name="success">/message.jsp</result>
		</global-results>
		<action name="list_*" class="cn.ljf.HelloWorldAction" method="{1}">
			<interceptor-ref name="permissionStack"></interceptor-ref><!-- 添加攔截器 -->
		</action>
	</package>