Java通过网络请求代理访问外部接口

@Autowired
RestTemplate restTemplate;

@PostConstruct
public void init() {
    logger.info("---------------加载电子身份证服务接口配置---------------");
    SimpleClientHttpRequestFactory simpleClientHttpRequestFactory = new SimpleClientHttpRequestFactory();
    Proxy proxy = new Proxy(Proxy.Type.HTTP, new InetSocketAddress("172.16.18.10", 9000));//配置代理服务器
    simpleClientHttpRequestFactory.setProxy(proxy);
    restTemplate = new RestTemplate(simpleClientHttpRequestFactory);
}

public Object call(String url, Map param){
        HttpHeaders httpHeaders = new HttpHeaders();
        httpHeaders.setContentType(MediaType.APPLICATION_JSON);
        param.put("username",username);
        param.put("token",token);
        String requestBody = JSON.toJSONString(param);
        logger.info("三门峡接口url:{},入参:{}",url,requestBody);
        HttpEntity httpEntity = new HttpEntity(requestBody, httpHeaders);
        String r = restTemplate.postForObject(url, httpEntity, String.class);
        JSONObject jsonObject = JSONObject.parseObject(r);
        logger.info("三门峡接口url:{},返回结果:{}",url,jsonObject);
        return jsonObject;
    }