struts2--使用自定义拦截器

你的名字 2024-02-18 00:28 13阅读 0赞

引言：做一个后台管理系统，这个系统为企业内部系统，如果不登录时没有权限访问此系统的。这时，可以使用拦截器拦截非法登录的用户。

自定义拦截器需要实现接口com.opensymphony.xwork2.interceptor.Interceptor。当然struts2提供了接口的实现类AbstractInterceptor,继承之，重新方法即可。

拦截器代码：

package com.Interceptor;
    
    import com.opensymphony.xwork2.ActionContext;
    import com.opensymphony.xwork2.ActionInvocation;
    import com.opensymphony.xwork2.interceptor.AbstractInterceptor;
    
    public class LoginInterceptor extends AbstractInterceptor{
    
    	@Override
    	public String intercept(ActionInvocation invocation) throws Exception {
    		 String user =  (String) ActionContext.getContext().getSession().get("user");
    		 if(null == user){
    			 ActionContext actionContext = invocation.getInvocationContext();//也可ActionContext.getContext();获取
    			 actionContext.put("tishi", "您还没有登录！请先登录！");
    			 return "login";
    		 }
    		 return invocation.invoke() ;//用户已经登录，进行后续操作
    	}
     
    }

struts.xml配置：

<?xml version="1.0" encoding="UTF-8"?>
    <!DOCTYPE struts PUBLIC
        "-//Apache Software Foundation//DTD Struts Configuration 2.1.7//EN"
        "http://struts.apache.org/dtds/struts-2.1.7.dtd">
        
    <struts>
     <package name="default" namespace = "/" extends = "struts-default">
        <interceptors>
          <interceptor name="loginInterceptor" class="com.Interceptor.LoginInterceptor"/>
          <interceptor-stack name="myStack">
            <interceptor-ref name="loginInterceptor"/>
            <interceptor-ref name="defaultStack"/>
          </interceptor-stack>
        </interceptors>
        
        <default-interceptor-ref name="myStack"/>
        
         <action name="login" class = "com.action.LoginAction">
           <result name = "success">/ok.jsp</result>
           <result name = "login">/index.jsp</result>
           <interceptor-ref name="defaultStack"/>
         </action>
         
         <action name="check" class = "com.action.CheckAction">
           <result name = "success">/check_ok.jsp</result>
           <result name = "login">/index.jsp</result>
         </action>
      </package>
    </struts>

在Action中引用拦截器，则默认拦截器将不起作用；由于登录方法不需要拦截，故不需要拦截器。

LoginAction.java

package com.action;
    
    import com.opensymphony.xwork2.ActionContext;
    import com.opensymphony.xwork2.ActionSupport;
    
    @SuppressWarnings("serial")
    public class LoginAction extends ActionSupport{
      private String username;
      private String password ;
    
    public String execute() {
    	  if(username.equals("admin") && password.equals("admin")){
    		  ActionContext.getContext().getSession().put("user", username);
    		  return SUCCESS;
    	  }else {
    		  return LOGIN;
    	  }
    	
    }
      
    public String getUsername() {
    	return username;
    }
    public void setUsername(String username) {
    	this.username = username;
    }
    public String getPassword() {
    	return password;
    }
    public void setPassword(String password) {
    	this.password = password;
    }
      
    }

登录界面：index.jsp

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
    <%@ taglib prefix = "s" uri = "/struts-tags" %>
    <%
    String path = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
    %>
    
    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
    <html>
      <head>
        <base href="<%=basePath%>">
        
        <title>My JSP 'index.jsp' starting page</title>
    	<meta http-equiv="pragma" content="no-cache">
    	<meta http-equiv="cache-control" content="no-cache">
    	<meta http-equiv="expires" content="0">    
    	<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    	<meta http-equiv="description" content="This is my page">
    	
      </head>
      
      <body>
      <s:property value = "tishi"/>
      <form action="login" method = "post">
        <s:textfield name = "username" label = "用户名"></s:textfield><br><br>
        <s:password name = "password" label = "密码"></s:password><br><br>
        <s:submit value = "登录"></s:submit>
       </form>
      </body>
    </html>

通常我们会遇到一段时间后刷新网页需要重新登录，也是拦截器在起作用，此时需要在web.xml中配置session作用的时间。

<session-config>
        <session-timeout>1</session-timeout>
      </session-config>

一分钟后失效