解决Spring Boot 拦截器注入service为空的问题

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1.需要在拦截器上加@Component

@Componentpublic class MyInterceptor implements HandlerInterceptor {    //想要注入的类    @Autowired    UserService userService;    @Override    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {        System.out.println("request before 拦截");        return true;    }    @Override    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {        System.out.println("post 拦截");    }    @Override    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {        System.out.println("after 拦截");    }}

2.进行拦截器配置

@Configurationpublic class MyWebAppConfigurer extends WebMvcConfigurerAdapter {    //关键，将拦截器作为bean写入配置中    @Bean    public MyInterceptor myInterceptor(){        return new MyInterceptor();    }    @Override    public void addInterceptors(InterceptorRegistry registry) {        //多个拦截器组成一个拦截器链        // addPathPatterns用于添加拦截规则        // excludePathPatterns用户排除拦截        registry.addInterceptor(myInterceptor()).addPathPatterns("/**"); //对来自/** 全路径请求进行拦截        super.addInterceptors(registry);    }}

这样就可以在拦截器中注入service和其他带有注解的类了，而不会再出现注入的注解为空的情况了，美滋滋(●’◡’●)。