SpringBoot学习笔记（六）：配置拦截器，控制登录跳转

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总共分2步：

• 配置自己的拦截器；
• 在web的配置文件中，实例化上面的拦截器，并添加规则；

拦截器代码：MyInterceptor.java

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
        logger.info("------preHandle------");
        //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()+"/admin/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

    }

}

web配置文件：WebConfig.java

@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("/adminUser/login");
        super.addInterceptors(registry);
    }

}