在HttpClient请求的时候，返回结果解析时出现java.io.IOException: Attempted read from closed stream. 异常，解决

HttpClient中的请求，一个方法中只能请求一次。

解决方案：

在springBoot中使用restTemplate的方法：

工具类：

/**
 * @author xwolf
 * @since 1.8
 **/
public class RestUtil {
    /**
     * get 请求
     * @param url 请求的url
     * @param map  参数
     * @param clazz 返回结果类型
     * @param <T>
     * @return
     */
    public static <T> T get(String url, Map,Object> map,Class<T> clazz){
        RestTemplate restTemplate = new RestTemplate();
        ResponseEntity<T> responseEntity = restTemplate.getForEntity(url,clazz,map);
        return responseEntity.getBody();
    }

    /**
     * https://www.programcreek.com/java-api-examples/index.php?class=org.springframework.web.client.RestTemplate&method=postForEntity
     * @param url 请求的结果
     * @param map   请求参数
     * @param clazz  返回结果类型
     * @param <T>
     * @return
     */
    public static <T> T post(String url, MultiValueMap,Object> map, Class<T> clazz){
        RestTemplate restTemplate = new RestTemplate();
        ResponseEntity<T> responseEntity = restTemplate.postForEntity(url,map,clazz);
        return responseEntity.getBody();
    }


    /**
     * 各種請求
     * https://www.programcreek.com/java-api-examples/index.php?class=org.springframework.web.client.RestTemplate&method=exchange
     * 
     * HttpHeaders headers = new HttpHeaders();
     * headers.add("access","token");
     * MultiValueMap,Object> map = new LinkedMultiValueMap<>();
     * map.add("username","rwrwer");
     * HttpEntity,Object>> entity = new HttpEntity<>(map,headers);
     * String content = RestUtil.exchange(url, HttpMethod.POST,entity,String.class);
     * 
     * @param url
     * @param httpMethod
     * @param httpEntity
     * @param clazz
     * @param <T>
     * @return
     */
    public static <T> T exchange(String url, HttpMethod httpMethod,HttpEntity httpEntity,Class<T> clazz){
        RestTemplate restTemplate = new RestTemplate();
        ResponseEntity<T> responseEntity =  restTemplate.exchange(url,httpMethod,httpEntity,clazz);
        return responseEntity.getBody();
    }
}