httpClient报错Unresolved compilation problem

背景：调用的url外部api网络是可达的，代码我在本机和测试环境都没问题,api应该是没问题的，但是在正式环境会报错如下。httpClient版本是4.1，项目JDK是1.6

报错日志

  Caused by: 
  java.lang.Error: Unresolved compilation problem: 
    at com.baosight.pscs.common.httpClientUtils.doPostJson(httpClientUtils.java:82)

代码部分

public static String doPostJson(String url, String json) throws Exception{
       // 创建Httpclient对象
        HttpClient httpClient = new DefaultHttpClient();
        System.out.println("######################");
           String resultString = "";
           HttpResponse response = null;
           try {
               HttpPost httpPost = new HttpPost(url);
               System.out.println("---------->  setURL:" + url);
               httpPost.setHeader("Content-Type", "application/json;charset=UTF-8");
               System.out.println("---------->  Header");

               // 创建请求内容
               //StringEntity entity = new StringEntity(json, ContentType.APPLICATION_JSON);
                StringEntity postingString = new StringEntity("{\"account\":\"admin\",\"password\":\"9cbf8a4dcb8e30682b927f352d6559a0\"}");
                System.out.println("---------->  postingString:" + postingString);
                postingString.setContentType("application/json");
                //参数传入

                httpPost.setEntity(postingString);
                System.out.println("---------->  setEntity");
                response = httpClient.execute(httpPost);
                System.out.println("---------->  execute" + httpPost.toString());
                HttpEntity entity = response.getEntity();
                resultString = EntityUtils.toString(response.getEntity(), "utf-8");
                System.out.println(resultString);

           } catch (Exception e) {
               e.printStackTrace();
               throw e;
           } finally {
               httpClient.getConnectionManager().shutdown();
           }
           return resultString;
   }

看报错是编译问题。仔细检查一下82行，或者用restTemplate