1、第一步创建一个类实现HandlerInterceptor接口，重写接口的方法

@Component
public class UserSecurityInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        return true;
    }

    @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、创建一个类继承WebMvcConfigurationSupport类并重写其方法

//    以下WebMvcConfigurerAdapter 比较常用的重写接口
//    /** 解决跨域问题 **/
//    public void addCorsMappings(CorsRegistry registry) ;
//    /** 添加拦截器 **/
//    void addInterceptors(InterceptorRegistry registry);
//    /** 这里配置视图解析器 **/
//    /** 视图跳转控制器 **/
//    void addViewControllers(ViewControllerRegistry registry);
//    void configureViewResolvers(ViewResolverRegistry registry);
//    /** 配置内容裁决的一些选项 **/
//    void configureContentNegotiation(ContentNegotiationConfigurer configurer);
//    /** 视图跳转控制器 **/
//    void addViewControllers(ViewControllerRegistry registry);
//    /** 静态资源处理 **/
//    void addResourceHandlers(ResourceHandlerRegistry registry);
//    /** 默认静态资源处理器 **/
//    void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer);

@Configuration
public class WebMvcConfig extends WebMvcConfigurationSupport {

    @Autowired
    private UserSecurityInterceptor securityInterceptor;

   /** 添加拦截器 **/
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        // addPathPatterns 用于添加拦截规则
        // excludePathPatterns 用于排除拦截
        registry.addInterceptor(securityInterceptor).addPathPatterns("/**")
                .excludePathPatterns("/user/login")
                .excludePathPatterns("/swagger-resources/**", "/webjars/**", "/v2/**", "/swagger-ui.html/**")
                .excludePathPatterns("/static/**");
        super.addInterceptors(registry);
    }

  /** 静态资源处理 **/
    @Override
    protected void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("swagger-ui.html")
                .addResourceLocations("classpath:/META-INF/resources/");
        registry.addResourceHandler("/webjars/**")
                .addResourceLocations("classpath:/META-INF/resources/webjars/");
    }

    /** 解决跨域问题 **/
    @Override
    public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**")
                .allowedOrigins("*")
                .allowedMethods("GET", "POST", "DELETE", "PUT", "HEAD", "OPTIONS")
                .allowedHeaders("Origin", "Accept", "X-Token", "Content-Type", "Access-Control-Request-Method", "Access-Control-Request-Headers")
                //设置是否允许跨域传cookie
                .allowCredentials(true)
                //设置缓存时间，减少重复响应
                .maxAge(3600);
    }

    private CorsConfiguration addCorsConfig() {
        CorsConfiguration corsConfiguration = new CorsConfiguration();
        List<String> list = new ArrayList<>();
        list.add("*");
        corsConfiguration.setAllowedOrigins(list);
        corsConfiguration.setAllowCredentials(true);
        /**
         *请求常用的三种配置，*代表允许所有，当时你也可以自定义属性（比如header只能带什么，只能是post方式等等）
         */
        corsConfiguration.addAllowedOrigin("*");
        corsConfiguration.addAllowedHeader("*") ;
        corsConfiguration.addAllowedMethod("*");
        return corsConfiguration;
    }

    @Bean
    public CorsFilter corsFilter() {
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        source.registerCorsConfiguration("/**", addCorsConfig());
        return new CorsFilter(source);
    }

    /**
     * 以下四个方法解决中文乱码问题
     *
     * @return
     */
    @Bean
    public HttpMessageConverter<String> responseBodyConverter() {
        StringHttpMessageConverter converter = new StringHttpMessageConverter(Charset.forName("UTF-8"));
        return converter;
    }

    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        super.configureMessageConverters(converters);
        //解决中文乱码
        converters.add(responseBodyConverter());
        //解决 添加解决中文乱码后 上述配置之后，返回json数据直接报错 500：no convertter for return value of type
        converters.add(messageConverter());
    }

    @Bean
    public MappingJackson2HttpMessageConverter messageConverter() {
        MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
        converter.setObjectMapper(getObjectMapper());
        return converter;
    }

    @Bean
    public ObjectMapper getObjectMapper() {
        return new ObjectMapper();
    }
}