java后端解决跨域的几种问题解决

public class SimpleCORSFilter implements Filter{

   @Override

   public void destroy() {

   }

   @Override

   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" );

       response.setHeader( "Access-Control-Max-Age" , "3600" );

       response.setHeader( "Access-Control-Allow-Headers" , "x-requested-with" );

       chain.doFilter(req, res);

   }

   @Override

   public void init(FilterConfig arg0) throws ServletException {

   } 

}

< filter >

    < filter-name >cors</ filter-name >

    < filter-class >com.ssm.web.filter.SimpleCORSFilter</ filter-class >

   </ filter >

   < filter-mapping >

    < filter-name >cors</ filter-name >

    < url-pattern >/*</ url-pattern >

   </ filter-mapping >

</ filter >

response.setHeader( "Access-Control-Allow-Origin" , "*" );

   response.setHeader( "Access-Control-Allow-Methods" , "POST, GET, OPTIONS, DELETE" );

   response.setHeader( "Access-Control-Max-Age" , "3600" );

   response.setHeader( "Access-Control-Allow-Headers" , "x-requested-with" );

try {

   HttpClient client = HttpClients.createDefault();      //client对象

   HttpGet get = new HttpGet( "http://localhost:8080/test" );  //创建get请求

   CloseableHttpResponse response = httpClient.execute(get);  //执行get请求

   String mes = EntityUtils.toString(response.getEntity());  //将返回体的信息转换为字符串

   System.out.println(mes);

} catch (ClientProtocolException e) {

   e.printStackTrace();

} catch (IOException e) {

   e.printStackTrace();

}

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;

/**

  * 实现基本的跨域请求

  * @author linhongcun

  *

  */

@Configuration

public class CorsConfig {

   @Bean

   public CorsFilter corsFilter() {

     final UrlBasedCorsConfigurationSource urlBasedCorsConfigurationSource = new UrlBasedCorsConfigurationSource();

     final CorsConfiguration corsConfiguration = new CorsConfiguration();

     /*是否允许请求带有验证信息*/

     corsConfiguration.setAllowCredentials(true);

     /*允许访问的客户端域名*/

     corsConfiguration.addAllowedOrigin("*");

     /*允许服务端访问的客户端请求头*/

     corsConfiguration.addAllowedHeader("*");

     /*允许访问的方法名,GET POST等*/

     corsConfiguration.addAllowedMethod( "*" );

     urlBasedCorsConfigurationSource.registerCorsConfiguration( "/**" , corsConfiguration);

     return new CorsFilter(urlBasedCorsConfigurationSource);

   }

}

server {

     listen    80;

     server_name HdhCmsTestmy测试数据;

     location /A {

       proxy_pass http: //a .a测试数据:81 /A ;

       index index.html index.htm;

     }

     location /B {

       proxy_pass http: //b .b测试数据:81 /B ;

       index index.html index.htm;

     }

   }

server {

     listen    80;

     server_name b.b测试数据;

     location /Api {

       proxy_pass http: //b .b测试数据:81 /Api ;

       index index.html index.htm;

     }

   }