使用Httpclient 完美解决服务端跨域问题

package com.example.util;
 
import java.net.URI;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.utils.URIBuilder;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
/**
 *body 参数参数
 * HttpClient工具类
 */
public class HttpUtil {
	public static String doPost(String url,String action ,String body) {
		 String result = null;
         HttpClient client = HttpClients.createDefault();
         URIBuilder builder = new URIBuilder();
         URI uri = null;
         try {
             uri = builder.setScheme(\"http\")
                       .setHost(url)  //  127.0.0.1:9528/registration_server  --- \"127.0.0.1:9528\"
                      .setPath(action)					//\"/registration_server/api/getToken\"
                      .build();
            
            HttpPost post = new HttpPost(uri);
            //设置请求头
            post.setHeader(\"Content-Type\", \"application/json\");
            
//            String body = \"{\\\"channelNo\\\": \\\"888888\\\",\\\"password\\\": \\\"123456\\\"}\";
           //设置请求体
           post.setEntity(new StringEntity(body));
            //获取返回信息
            HttpResponse response = client.execute(post);
            HttpEntity entity=response.getEntity();
//            String rtn=EntityUtils.toString(entity);
//            JSON  obj=(JSON ) JSON .parse(rtn);
//            System.out.println(\"data======\"+obj.get(\"data\"));
//            result =(String) obj.get(\"data\");
            return EntityUtils.toString(entity,\"utf-8\");
        } catch (Exception e) {
            System.out.println(\"接口请求失败\"+e.getStackTrace());
        }
//        System.out.println(result);
//		return result;
         return \"\";
	}
}