RestTemplate中使用ParameterizedTypeReference参数化类型支持泛型，主要是List

在使用http请求时，往往会封装一个统一的结果类

package com.plateno.booking.sync.ebk.process.http.response;public class  InternalDataServiceResult <T> {private String resultCode;private String resultMsg;private T data;public String getResultCode() {return resultCode;}public void setResultCode(String resultCode) {this.resultCode = resultCode;}public String getResultMsg() {return resultMsg;}public void setResultMsg(String resultMsg) {this.resultMsg = resultMsg;}public T getData() {return data;}public void setData(T data) {this.data = data;}@Overridepublic String toString() {return "InternalDataServiceResult [resultCode=" + resultCode + ", resultMsg=" + resultMsg + ", data=" + data+ "]";}/** * 是否操作成功 * @return */public boolean isSuccess(){return "0".equals(this.resultCode);}}

data是实际返回的数据（程序需要的），这里是个T泛型，当T是类似List<OrderInnDay>时，使用普通的RestTemplate.postForObject是无法知道OrderInnDay的类型的，最终T会是List<LinkedHashMap>，这不是我们想要的结果，恰好RestTemplate有其它的方法可以代替，比较麻烦（怪spring没有很好的封装上层方法）

package com.plateno.booking.util;import java.util.List;import java.util.Map;import javax.annotation.PostConstruct;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.context.annotation.Lazy;import org.springframework.core.ParameterizedTypeReference;import org.springframework.http.HttpEntity;import org.springframework.http.HttpMethod;import org.springframework.stereotype.Component;import org.springframework.web.client.RestTemplate;import com.plateno.booking.bean.InternalDataServiceResult;@Component@Lazy(false)public class RestTemplateUtil {@Autowiredprivate RestTemplate xRestTemplate;private static RestTemplate restTemplate;public static <T> InternalDataServiceResult<List<T>> exchangeAsList(HttpMethod method,String url, Map<String,Object> params, ParameterizedTypeReference<InternalDataServiceResult<List<T>>> responseType) {    HttpEntity requestEntity = new HttpEntity(params);return restTemplate.exchange(url, method, requestEntity, responseType).getBody();}public static <T> InternalDataServiceResult<List<T>> postForList(String url, Map<String,Object> params, ParameterizedTypeReference<InternalDataServiceResult<List<T>>> responseType){return exchangeAsList(HttpMethod.POST, url, params, responseType);}@PostConstructpublic void init(){restTemplate = this.xRestTemplate;}public static RestTemplate getRestTemplate() {return restTemplate;}public static void setRestTemplate(RestTemplate restTemplate) {RestTemplateUtil.restTemplate = restTemplate;}public RestTemplate getxRestTemplate() {return xRestTemplate;}public void setxRestTemplate(RestTemplate xRestTemplate) {this.xRestTemplate = xRestTemplate;}}

当需要使用post请求，返回List<OrderInnDay>时，即可这样使用：

public List<OrderInnDay> getOrderInnDayList(String orderCode,Integer memberId){Map<String, Object> params = new HashMap<>();params.put("orderCode", orderCode);params.put("memberId", memberId);String url = apiProperties.getInternalDataService().getGetOrderInnDayList();log.info("query orderInnDayList,url：{},params:{}", url ,JsonUtil.toJson(params));                //use postForListInternalDataServiceResult<List<OrderInnDay>> result = RestTemplateUtil.postForList(url, params, new ParameterizedTypeReference<InternalDataServiceResult<List<OrderInnDay>>>(){});if (!result.isSuccess()) {log.warn("query orderInnDayList failed：url:{},params：{},response：{}", url,JsonUtil.toJson(params), JsonUtil.toJson(result));}return result.getData();}