Simple implementation of Struts2 permission interceptor

Action request class

package action;

public class SystemAction {

	public String execute() {
		return "success";
	}
	
}

Custom interceptor

package interceptors;

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

public class PermissionInterceptor extends AbstractInterceptor {

	@Override
	public String intercept(ActionInvocation invocation) throws Exception {
		String currentUser = (String)ActionContext.getContext().getSession().get("currentUser");
		if (null != currentUser) {
			// 执行Action中的方法或调用其后的拦截器
			return invocation.invoke();
		}
		return "fail"; // 当前用户为null时跳转至fail视图
	}

}

Struts2 core configuration struts.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC
	"-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
	"http://struts.apache.org/dtds/struts-2.3.dtd">

<struts>
	<package name="strutsCore" namespace="/interceptor" extends="struts-default">
		<interceptors>
			<!-- 注册自定义PermissionInterceptor拦截器 -->
			<interceptor name="permissionInterceptor" class="interceptors.PermissionInterceptor"/>
		</interceptors>
		<action name="systemAction" class="action.SystemAction">
			<!-- 为Action关联自定义拦截器，此后系统默认的拦截器自动失效 -->
			<interceptor-ref name="permissionInterceptor"/>
			<!-- 开启strust-default.xml中的默认拦截器栈 -->
			<interceptor-ref name="defaultStack"/>
			<result name="success">/welcome.jsp</result>
			<result name="fail">/fail.jsp</result>
		</action>
	</package>
</struts>

View: index.jsp

<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>Index</title>
	</head>
	<body>
		<h2>This is page index!</h2>
	</body>
</html>

View: welcome.jsp

<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>Welcome</title>
	</head>
	<body>
		<h2>This is page welcome!</h2>
	</body>
</html>

View: login.jsp

<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>Login</title>
	</head>
	<body>
		<% session.setAttribute("currentUser", "WanAkiko"); %>
		<h2>提示：登录成功，WanAkiko，欢迎回来！</h2>
	</body>
</html>

View: logout.jsp

<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>Logout</title>
	</head>
	<body>
		<% session.removeAttribute("currentUser"); %>
		<h2>提示：当前用户已退出！</h2>
	</body>
</html>

View: fail.jsp

<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>Fail</title>
	</head>
	<body>
		<h2>This is page fail!</h2>
	</body>
</html>

Use Chrome and IE to test the custom interceptor.
Insert picture description here

Test results: After the project is started, index.jsp is accessed. If you are not logged in, the fail.jsp is accessed through SystemAction. If you enter login.jsp, you will make a request to SystemAction again. Then visit welcom.jsp. Afterwards, if you execute logout.jsp and then execute SystemAction, you will also enter fail.jsp, which shows that our custom permission interceptor is indeed in effect.

Simple implementation of Struts2 permission interceptor

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