springboot 采用HttpClient获取天气预报 异常及原因

2018-10-04 15:18:25.815 ERROR 10868 --- [nio-8080-exec-5] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.web.client.HttpServerErrorException: 502 Bad Gateway] with root cause

org.springframework.web.client.HttpServerErrorException: 502 Bad Gateway
    at org.springframework.web.client.DefaultResponseErrorHandler.handleError(DefaultResponseErrorHandler.java:97) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
    at org.springframework.web.client.DefaultResponseErrorHandler.handleError(DefaultResponseErrorHandler.java:79) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RELEASE]
    at org.springframework.web.client.ResponseErrorHandler.handleError(ResponseErrorHandler.java:63) ~[spring-web-5.0.9.RELEASE.jar:5.0.9.RE
LEASE]

    private WeatherResponse doGetWeather(String uri){
        //通过spring  restTemplate 客户端发送请求获取 String类型响应实体
        ResponseEntity respString = restTemplate.getForEntity(uri, String.class);

        //Springboot内部集成了json操作对象
        ObjectMapper objectMapper = new ObjectMapper();
        WeatherResponse resp=null;
        String strBody = null;
        //通过响应客户端获取状态码判断是否为成功状态码
        if(respString.getStatusCodeValue()==200){
            //获取响应实体内容实体
            strBody = respString.getBody();
        }
        try {
            //通过json操作对象将string 类型数据转为指定类型对象
            resp = objectMapper.readValue(strBody, WeatherResponse.class);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return resp;
    }
}

public class WeatherResponse implements Serializable{

    private Weather weather;

    private Integer status;

    private String desc;