RestTemplate自定义请求失败异常处理示例解析

@Test
public void testEntity() {
   String url = "http://jsonplaceholder.typicode.com/postss/1";
   ResponseEntity<String> responseEntity
               = restTemplate.getForEntity(url, String.class);  //这行抛出异常
   //下面两行代码执行不到
   HttpStatus statusCode = responseEntity.getStatusCode(); // 获取响应码
   System.out.println("HTTP 响应状态：" + statusCode);
}

public enum Series {
   INFORMATIONAL(1),  // 1xx/100
   SUCCESSFUL(2),  // 2xx/100
   REDIRECTION(3), // 3xx/100
   CLIENT_ERROR(4), // 4xx/100   ,客户端异常
   SERVER_ERROR(5); // 5xx/100 ，服务端异常
}

public class MyRestErrorHandler implements ResponseErrorHandler {
    /**
     * 判断返回结果response是否是异常结果
     * 主要是去检查response 的HTTP Status
     * 仿造DefaultResponseErrorHandler实现即可
     */
    @Override
    public boolean hasError(ClientHttpResponse response) throws IOException {
        int rawStatusCode = response.getRawStatusCode();
        HttpStatus statusCode = HttpStatus.resolve(rawStatusCode);
        return (statusCode != null ? statusCode.isError(): hasError(rawStatusCode));
    }
    protected boolean hasError(int unknownStatusCode) {
        HttpStatus.Series series = HttpStatus.Series.resolve(unknownStatusCode);
        return (series == HttpStatus.Series.CLIENT_ERROR || series == HttpStatus.Series.SERVER_ERROR);
    }
    @Override
    public void handleError(ClientHttpResponse response) throws IOException {
        // 里面可以实现你自己遇到了Error进行合理的处理
        //TODO 将接口请求的异常信息持久化
    }
}