Eclipse搭建SpringBoot（五）使用拦截器验证用户登录

2017-06-26

技术

1.使用拦截器验证用户登录的手段

目前网上提供的拦截器验证用户登录主要分为两种手段：

把拦截器声明成一个注解加到 Controller 上

如：springboot(八)拦截器之验证登录

在 WebConfig.java 中添加拦截器相关规则，

如：SpringBoot学习笔记（六）：配置拦截器，控制登录跳转

本文中采用第二种方案，因为它实现起来比较简单。

2.实现步骤

2.1.创建拦截器

在项目中添加 com.yun.interceptor 包，并在其中添加 MyInterceptor 类，其内容如下：

package com.yun.interceptor;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
public class MyInterceptor implements HandlerInterceptor {
    Logger logger = LoggerFactory.getLogger(MyInterceptor.class);
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
            throws Exception {
        // TODO Auto-generated method stub
        //获取session
        HttpSession session = request.getSession(true);
        //判断用户ID是否存在，不存在就跳转到登录界面
        if(session.getAttribute("userId") == null){
            logger.info("------:跳转到login页面！");
  response.sendRedirect(request.getContextPath()+"/login");
            return false;
        }else{
            session.setAttribute("userId", session.getAttribute("userId"));
            return true;
        }
    }
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
            ModelAndView modelAndView) throws Exception {
        // TODO Auto-generated method stub
    }
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
            throws Exception {
        // TODO Auto-generated method stub
    }
}

2.2.添加 WebConfig.java 文件

在项目中创建 com.yun.config 包，创建 WebConfig.java 文件，其内容如下：

package com.yun.config;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.util.ResourceUtils;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import com.yun.interceptor.MyInterceptor;
@Configuration
@EnableWebMvc
@ComponentScan
public class WebConfig extends WebMvcConfigurerAdapter implements ApplicationContextAware {
    private ApplicationContext applicationContext;
    public WebConfig(){
        super();
    }
    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/static/**").addResourceLocations(ResourceUtils.CLASSPATH_URL_PREFIX+"/static/");
        registry.addResourceHandler("/templates/**").addResourceLocations(ResourceUtils.CLASSPATH_URL_PREFIX+"/templates/");
        super.addResourceHandlers(registry);  
        }
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        this.applicationContext = applicationContext;
    } 
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        //拦截规则：除了login，其他都拦截判断
        registry.addInterceptor(new MyInterceptor()).addPathPatterns("/**").excludePathPatterns("/login");
        super.addInterceptors(registry);
    }
}

2.3.修改 YunApplication.java 文件

在 YunApplication.java 文件中添加如下代码：

package com.yun;
import javax.servlet.http.HttpSession;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import com.yun.service.LoggerService;
import com.yun.service.ScopeService;
import com.yun.service.UserService;
/*
 * 控制器使用示例
 */
@SpringBootApplication
@Controller
public class YunApplication {
  
    @ResponseBody
	@RequestMapping("/")
	public String greeting() {	
		return "Hello World!";
	}
// 下面是需要添加到 YunApplication.java 中的代码
// 本文件中的其他内容只是为了说明这段代码应该添加到什么位置
    
    @ResponseBody
    @RequestMapping("/login")
    public String login(HttpSession session) {
    	session.setAttribute("userId", "jackie");
        return "login";
    }
  
 // 需要添加的代码到此为止
}