1、创建自定义拦截器类(UserTokenInterceptor)并实现HandlerInterceptor 接口，再重写方法，代码如下：
public class UserTokenInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
log.info("进入拦截器啦、、");
return true; // true即可放行，false则不放行
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
}
}
2、配置Web拦截器(WebMvcConfig)并实现Spring的WebMvcConfigurer接口
在Spring Boot 1.5版本都是靠重写WebMvcConfigurerAdapter的方法来添加自定义拦截器，消息转换器等。SpringBoot 2.0 后，该类被标记为@Deprecated（弃用）。官方推荐直接实现WebMvcConfigurer或者直接继承WebMvcConfigurationSupport，方式一实现WebMvcConfigurer接口（推荐）
复写addInterceptors方法，添加自己的拦截器
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
@Configuration
public class WebMvcConfig implements WebMvcConfigurer {
@Override
public void addInterceptors(InterceptorRegistry registry) {
// 注册拦截器
registry.addInterceptor(getUserTokenInterceptor()).addPathPatterns("/index/session");
// 一定要加
WebMvcConfigurer.super.addInterceptors(registry);
}
// @Bean
public UserTokenInterceptor getUserTokenInterceptor() {
return new UserTokenInterceptor();
}
}
3、编写测试Controller
@RestController
@RequestMapping("/index")
public class IndexController {
@Deprecated
@GetMapping("/session")
public Object getSession(HttpServletRequest request) {
HttpSession session = request.getSession();
session.setAttribute("name", "lequal");
session.setMaxInactiveInterval(3600);
String name = (String) session.getAttribute("name");
System.out.println("获取的名字是：" + name);
return name;
}
}
4、访问URL地址
如果preHandle方法中return false的话浏览器访问是看不到返回的内容的，因为被拦截住了，就相当于卡在那里了。
