在线测试跨域请求打开浏览器，打开一个网页(比如掘金)， 按F12调出开发者工具，google 浏览器开发者工具界面如下：

2在 Console 输入下面的代码：

var xhr = new XMLHttpRequest();xhr.open('GET', ';);xhr.send(null);xhr.onload = function(e) {    var xhr = e.target;    console.log(xhr.responseText);}

3。回车运行代码，如果出现跨域问题，会提示下面的信息

JAVA 处理跨域基于WebMvcConfigurerAdapter配置加入Cors的跨域

import org.springframework.context.annotation.Configuration; import org.springframework.web.servlet.config.annotation.CorsRegistry; import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter; @Configuration public class CorsConfig extends WebMvcConfigurationSupport {     @Override     public void addCorsMappings(CorsRegistry registry) {         registry.addMapping("/**");     } }复制代码

@Componentpublic class CorsInterceptor extends HandlerInterceptorAdapter {    private final Logger logger = LoggerFactory.getLogger(CorsInterceptor.class);    @Override    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) {	response.setHeader("Access-Control-Allow-Origin",request.getHeader("origin"));        response.setHeader("Access-Control-Allow-Credentials", "true");        response.setHeader("Access-Control-Allow-Methods", "GET, HEAD, POST, PUT, PATCH, DELETE, OPTIONS");        response.setHeader("Access-Control-Max-Age", "86400");        response.setHeader("Access-Control-Allow-Headers", "*");        // 如果是OPTIONS则结束请求        if (HttpMethod.OPTIONS.toString().equals(request.getMethod())) {            response.setStatus(HttpStatus.NO_CONTENT.value());            return false;        }        return true;    }}复制代码

@Configurationpublic class WebMvcConfig extends WebMvcConfigurationSupport{	@Recourse	private CorsInterceptor corsInterceptor;	/**	* 添加拦截器	*/	@Override	public void addInterceptors(InterceptorRegistry registry) {	   registry.addInterceptor(corsInterceptor);	}}复制代码

@Componentpublic class SimpleCORSFilter implements Filter {    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {        HttpServletResponse response = (HttpServletResponse) res;        response.setHeader("Access-Control-Allow-Origin", "*");        response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE, HEAD");        response.setHeader("Access-Control-Max-Age", "3600");        response.setHeader("Access-Control-Allow-Headers", "access-control-allow-origin, authority, content-type, version-info, X-Requested-With");        chain.doFilter(req, res);    }    public void init(FilterConfig filterConfig) {}    public void destroy() {}}复制代码

import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.web.cors.CorsConfiguration;import org.springframework.web.cors.UrlBasedCorsConfigurationSource;import org.springframework.web.filter.CorsFilter;@Configurationpublic class CorsConfig {    private CorsConfiguration buildConfig() {        CorsConfiguration corsConfiguration = new CorsConfiguration();        // 允许任何域名        corsConfiguration.addAllowedOrigin("*");        // 允许任何头        corsConfiguration.addAllowedHeader("*");        // 允许任何方法        corsConfiguration.addAllowedMethod("*");        return corsConfiguration;    }    @Bean    public CorsFilter corsFilter() {        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();        // 注册        source.registerCorsConfiguration("/**", buildConfig());        return new CorsFilter(source);    }}

问题配置多个跨域

2‘https网页不能调试http

Mixed Content: The page at '; was loaded over HTTP

3不安全的证书