跨域问题在web开发中最常见的问题之一，解决方式可以是从前端入手也可以是服务器端处理，今天先说一下后端的处理方式之一，其他方式希望大家提供：
使用springboot开发，通过继承DefaultCorsProcessor过滤放行的域名
代码如下：
public class CorsProcessor extends DefaultCorsProcessor {

private static final Logger LOGGER = LoggerFactory.getLogger(CorsProcessor.class);

/**
 * Check the origin and determine the origin for the response. The default
 * implementation simply delegates to
 * {@link org.springframework.web.cors.CorsConfiguration#checkOrigin(String)}.
 */
@Override
protected String checkOrigin(CorsConfiguration config, String requestOrigin) {
    //需要放行的域名

    try {
        if (requestOrigin != null) {
            URI uri = new URI(requestOrigin);
            if (uri.getHost().endsWith(".xx.com")) {
                LOGGER.debug("跨域处理器放行Origin:{}", requestOrigin);
                return requestOrigin;
            }
        }
    } catch (URISyntaxException e) {
        LOGGER.error("跨域转换错误",e);
    }
        return super.checkOrigin(config, requestOrigin);
    }

}

启动Bean中增加

@Configuration
public class FilterConfiguration {

    @Bean
    public FilterRegistrationBean corsFilter() {
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        CorsConfiguration config = new CorsConfiguration();
        config.setAllowCredentials(true);
        config.addAllowedOrigin("*");
        config.addAllowedHeader("*");
        config.addAllowedMethod("*");
        source.registerCorsConfiguration("/**", config);
        CorsFilter corsFilter = new CorsFilter(source);
        corsFilter.setCorsProcessor(new CorsProcessor());
        FilterRegistrationBean bean = new FilterRegistrationBean(corsFilter);
        bean.setOrder(1);
        return bean;
    }
}