스프링 인터셉터를 이용하여 로그인 상태를 검사하는 예 ( Spring MVC Interceptor Authentication example )
로그인을 거친 이용자에게는 Controller 클래스의 getTime() 메소드가 기능을 할 수 있도록 하고 아니면 로그인 폼을 보여주는 예
WEB-INF/web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<!-- The definition of the Root Spring Container shared by all Servlets and Filters -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/root-context.xml</param-value>
</context-param>
<!-- Creates the Spring Container shared by all Servlets and Filters -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- Processes application requests -->
<servlet>
<servlet-name>appServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/servlet-context.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>appServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<filter>
<filter-name>encodingFilter</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>encodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
</web-app>
SampleController.java
package org.kdea.interceptor;
import java.util.Date;
import javax.servlet.http.HttpSession;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
@Controller
public class SampleController {
@RequestMapping(value="/int/login", method=RequestMethod.GET)
public String login(){
return "interceptor/login_form";
}
@RequestMapping(value="/int/login", method=RequestMethod.POST)
public String login(@RequestParam String id,
@RequestParam String pwd,
HttpSession session){
if(id!=null && !id.equals("") && pwd!=null && !pwd.equals("")) {
session.setAttribute("login", true);
return "interceptor/login_success";
}
return "interceptor/login_fail";
}
@RequestMapping("/int/getTime")
@ResponseBody
public String getServerTime(){ // 로그인을 거친 사용자만 사용할 수 있도록 설정하려고 함
return new Date().toString();
}
}
서블릿 설정파일에 콘트롤러를 자동으로 찾을 수 있도록 설정하고 이용자의 요청 URL에 인터셉터를 연결한다
WEB-INF/spring/servlet-context.xml
................
<beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<beans:property name="prefix" value="/WEB-INF/views/" />
<beans:property name="suffix" value=".jsp" />
<beans:property name="contentType" value="text/html; charset=UTF-8"/>
</beans:bean>
................
<context:component-scan base-package="org.kdea.interceptor" />
.........
.............
<interceptors>
<interceptor>
<mapping path="/int/getTime"/> <!-- /int/* 을 사용하여 모든 기능에 앞서 인터셉터가 호출되도록 할 수 있음 -->
<beans:bean class="org.kdea.interceptor.AuthInterceptor" />
</interceptor>
</interceptors>
.........
AuthInterceptor.java
package org.kdea.interceptor;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
public class AuthInterceptor extends HandlerInterceptorAdapter {
@Override // 콘트롤러에 앞서 실행됨
public boolean preHandle(HttpServletRequest request,
HttpServletResponse response, Object handler) throws Exception {
if(request.getSession().getAttribute("login")==null){
response.sendRedirect("login"); // 콘트롤러에 선언된 login 요청으로 전환함
return false; // 다른 절차가 실행되지 않음
}
return true; // 다른 인터셉터나 콘트롤러가 이후에 호출됨
}
@Override // 콘트롤러 실행 후, 뷰 호출 전에 실행됨
public void postHandle(HttpServletRequest request,
HttpServletResponse response, Object handler,
ModelAndView modelAndView) throws Exception {
System.out.println("postHandle():after Controller, before View rendering");
}
@Override // 뷰가 실행된 후에 실행됨
public void afterCompletion(HttpServletRequest request,
HttpServletResponse response, Object handler, Exception ex)
throws Exception {
System.out.println("afterCompletion():after View rendered");
}
}
WEB-INF/views/login_success.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="EUC-KR">
<title>로그인 성공</title>
</head>
<body>
로그인에 성공했습니다<p>
Login success!
</body>
</html>
WEB-INF/views/login_fail.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="EUC-KR">
<title>로그인 실패</title>
</head>
<body>
로그인에 실패<p>
Login Failed!
</body>
</html>
WEB-INF/views/login_form.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="EUC-KR">
<title>로그인 폼</title>
</head>
<body>
로그인 폼<p>
<form action="login" method="post">
ID <input type="text" name="id">
PWD <input type="password" name="pwd">
<input type="submit" value="Login">
</form>
</body>
</html>