解决Spring Boot 拦截器注入service为空的问题

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

@Component
public 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

@Configuration
public 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(●’◡’●)。