Spring boot之登录拦截器

逃离我推掉我的手 2022-06-12 08:28 195阅读 0赞

首先，继承一个拦截器：

package com.cy.example.filter;
    
    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 LoginInterceptor implements HandlerInterceptor { 
    
        private Logger logger = LoggerFactory.getLogger(LoginInterceptor.class);
    
        public void postHandle(HttpServletRequest request,
                HttpServletResponse response, Object handler,
                ModelAndView modelAndView) throws Exception {
            // TODO Auto-generated method stub
    
        }
    
        public void afterCompletion(HttpServletRequest request,
                HttpServletResponse response, Object handler, Exception ex)
                throws Exception {
            // TODO Auto-generated method stub
    
        }
    
        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
            /*String url = request.getServletPath(); logger.info("----进入拦截器--url："+url+"-----"); if(url.contains("/system/user/validate")){ logger.info("----放过/system/user/validate-----"); return true; }*/
            if(session.getAttribute(WebConfig.LOGIN_USER) == null){
                logger.info("------跳转到login页面-----");
                response.sendRedirect(request.getContextPath()+"/index");
                return false;
            }else{
                session.setAttribute(WebConfig.LOGIN_USER, session.getAttribute(WebConfig.LOGIN_USER));
                return true;
            }
        }
    
    }

在preHandle方法中获取缓存中的用户名，如果没有则返回登录界面，如果有则通过拦截器。
    下面就把新写的拦截器注册一下：

package com.cy.example.filter;
    
    import org.springframework.context.annotation.ComponentScan;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
    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.ViewControllerRegistry;
    import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
    
    import com.cy.example.Application;
    
    @Configuration
    public class WebConfig extends WebMvcConfigurerAdapter{
    
        public static String LOGIN_USER = "loginUser";
    
        public WebConfig(){
            super();
        }
    
        @Override
        public void addResourceHandlers(ResourceHandlerRegistry registry) {
            registry.addResourceHandler("/static/**").addResourceLocations("classpath:/static/");
            registry.addResourceHandler("/templates/**").addResourceLocations("classpath:/templates/");
    
            super.addResourceHandlers(registry); 
        }
    
    
        @Override
        public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
            configurer.enable();
        }
    
        @Override
        public void addInterceptors(InterceptorRegistry registry) {
            //拦截规则：除了/index，/system/user/validate其他都拦截判断
            registry.addInterceptor(new LoginInterceptor()).addPathPatterns("/**").excludePathPatterns("/index","/system/user/validate");
            super.addInterceptors(registry);
        }
    
    }

这边在写的时候遇到点问题，在WebConfig类上多加了2个注解，分别是@EnableWebMvc  
@ComponentScan  
这两个注解一个是配置包扫描的，一个是启用Spring MVC支持。感觉加了这两个注解就是把spring boot的默认配置全部取消了，全部是由自己配置，这就导致了我的静态资源一直访问不到。  
addInterceptors  
这个方法是添加拦截器，  
registry.addInterceptor(new LoginInterceptor()).addPathPatterns(“/\*\*”).excludePathPatterns(“/index”,”/system/user/validate”);  
这个是使用拦截器拦截所有请求，除了”/index”,”/system/user/validate”这两个路径

addResourceHandlers(ResourceHandlerRegistry registry)这个方法是这边添加拦截器之后默认的静态资源路径失效，在这个方法中需要重新指定。