config类：

@Configuration
public class WebAdminInterceptorConfig implements WebMvcConfigurer {
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new WebAdminInterceptor())
                .addPathPatterns("/**")
                .excludePathPatterns("/static");
    }
}

Interceptor类：

public class WebAdminInterceptor implements HandlerInterceptor {

    @Autowired
    private RedisService redisService;

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        redisService.get("aaa"); //redisService为null
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

    }
}

问题描述:

在Interceptor中，自动注入的对象为null

解决方案:

修改Config类如下：

@Configuration
public class WebAdminInterceptorConfig implements WebMvcConfigurer {

    @Bean
    WebAdminInterceptor webAdminInterceptor(){
        return new WebAdminInterceptor();
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(webAdminInterceptor())
                .addPathPatterns("/**")
                .excludePathPatterns("/static");
    }
}