【Spring】SpringMVC之攔截器
阿新 • • 發佈：2017-07-17
https javax request orm bin 支持 exceptio 賬號 intern 
Spring的HandlerMapping處理器支持攔截器應用。當需要為某些請求提供特殊功能時，例如實現對用戶進行身份認證、登錄檢查等功能。
攔截器必須實現HandlerInterceptor接口
流程圖片實例:
使用步驟:
1. 編寫一個類 實現HandlerInterceptor接口
2. 配置applicationContext.xml
配置文件案例:
<mvc:interceptors> <mvc:interceptor> <!-- 要攔截的地址 --> <mvc:mapping path="/**"/> <!-- 匹配攔截地址 中的不攔截的地址 <mvc:exclude-mapping path=""/>--> <!-- 使用的攔截器類 --> <bean class="cn.xdl.filter.MyFilter"></bean> </mvc:interceptor> </mvc:interceptors>
案例：
控制器代碼：
package cn.xdl.controller; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.servlet.ModelAndView; import org.springframework.web.servlet.View; @Controller public class UserController { @RequestMapping(UserController.java"/login.do") public ModelAndView userLogin(String uname,String upass){ System.out.println(uname); System.out.println(upass); ModelAndView modelview=new ModelAndView("loginResult"); return modelview; } }
過濾器代碼：
package cn.xdl.user.filter; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.web.servlet.HandlerInterceptor; import org.springframework.web.servlet.ModelAndView; public class UserFilter implements HandlerInterceptor { @Override public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object arg2, Exception arg3) throws Exception { } @Override public void postHandle(HttpServletRequest request, HttpServletResponse response, Object arg2, ModelAndView arg3) throws Exception { } @Override public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object arg2) throws Exception { /* * return true 表示攔截通過 * return false 表示攔截不通過 * * 如果是攔截不通過用戶的頁面會出現一個大白屏，這個時候應該進行請求重定向，比如：response.sendRedirect("loginError.jsp") */ String uname = request.getParameter("uname"); String upass = request.getParameter("upass"); //對用戶的賬號和密碼進行簡單驗證 if(uname==null||upass==null||uname.length()<6||upass.length()<6){ //攔截 , response.sendRedirect("loginError.jsp"); return false; } return true; } }UserFilter.java
DispatcherServlet配置文件：
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd"> <!--指定掃描包--> <context:component-scan base-package="cn"></context:component-scan> <!--開啟掃描--> <mvc:annotation-driven/> <!--配置ModelAndView--> <bean id="viewResolve" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="viewClass" value="org.springframework.web.servlet.view.InternalResourceView"></property> <property name="prefix" value=""></property> <property name="suffix" value=".jsp"></property> </bean> <!--配置攔截器--> <mvc:interceptors> <mvc:interceptor> <!-- 要攔截的地址，這裏是攔截所有地址 --> <mvc:mapping path="/**"/> <!-- 匹配攔截地址中不用攔截的地址 <mvc:exclude-mapping path=""/> --> <!-- 指定的攔截器類 --> <bean class="cn.xdl.user.filter.UserFilter"></bean> </mvc:interceptor> </mvc:interceptors> </beans>dispatcher_serverlet-servlet.xml
web.xml配置文件：
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0"> <display-name>SpringFilterTest</display-name> <welcome-file-list> <welcome-file>index.html</welcome-file> </welcome-file-list> <servlet> <servlet-name>dispatcher_serverlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>dispatcher_serverlet</servlet-name> <url-pattern>*.do</url-pattern> </servlet-mapping> <filter> <filter-name>EncodingName</filter-name> <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class> <init-param> <param-name>encoding</param-name> <param-value>utf-8</param-value> </init-param> </filter> <filter-mapping> <filter-name>EncodingName</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> </web-app>web.xml
jsp代碼：
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>登錄失敗</title> </head> <body> 登錄失敗 </body> </html>loginError.jsp
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>結果頁面</title> </head> <body> 登錄成功 </body> </html>loginResult.java
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>用戶登錄</title> </head> <body> <form action="login.do" method="post"> 用戶名:<input type="text" name="uname" /><br/><br/> 密碼:<input type="password" name="upass" /><br/><br/> <input type="submit" value="登錄" /> </form> </body> </html>login.jsp
【Spring】SpringMVC之攔截器