java - RestTemplate在java中处理[image/jpg]响应内容类型

Question

抱歉，我是 Java Web 开发新手。

我有一些任务通过 HTTP Rest(GET 方法)从第 3 方公司获取用户个人资料图片。他们的 api 只能使用 header 参数上的 session id 来访问，并且 api 将返回一些 byte[] 数组，看起来像 'ÑÒBRSbâTr²ñ#‚4“â3C 等。

如何在 Rest 模板中处理内容类型为 image/jpg 的 Rest 响应？

我会尽力做到这一点

private RestTemplate restTemplate;

public byte[] getProfilePic(){
  String canonicalPath = "http://dockertest/bankingapp/customer/profpicFile";
  String sessionId= "MTQ4NzE5Mz...etc";

  HttpEntity<byte[]> request = new HttpEntity<byte[]>(null, getHeaders(true, "GET", null, canonicalPath, sessionId));
  //getHeaders() will return HttpHeaders with those parameter

  ResponseEntity<byte[]> response = null;
  try {
    response = this.restTemplate.exchange(uri, HttpMethod.GET, request, byte[].class);
  } catch( HttpServerErrorException hse ){
    throw hse;
  }
  return response;
}

此代码将返回错误

org.springframework.web.client.RestClientException: Could not extract response: no suitable HttpMessageConverter found for response type [[B] and content type [image/jpg]

任何建议或帮助将不胜感激!

谢谢

更新

使用 stackoveflower 建议我可以解决这个问题。

private RestTemplate restTemplate;

public byte[] getProfilePic(){
  String canonicalPath = "/mobile/customer/profpicFile";
  String sessionId= "MTQ4NzE5Mz...etc";

  HttpEntity<byte[]> request = new HttpEntity<byte[]>(null, getHeaders(true, "GET", null, canonicalPath, sessionId));
  //getHeaders() will return HttpHeaders with those parameter

  ResponseEntity<byte[]> response = null;
  try {
    restTemplate.getMessageConverters().add(new ByteArrayHttpMessageConverter());
    response = this.restTemplate.exchange(uri, HttpMethod.GET, request, byte[].class).getBody();
    return response;
  } catch( HttpServerErrorException hse ){
    throw hse;
  }
  return null;
}

关于HttpMessageConverter的注意事项，我可以直接添加一个ByteArrayHttpMessageConverter()，而不是使用列表

Answer 1

正如我所说，我想你必须使用正确的messageconverter 我会这样做:

private RestTemplate restTemplate;

public byte[] getProfilePic(){
  String canonicalPath = "http://dockertest/bankingapp/customer/profpicFile";
  String sessionId= "MTQ4NzE5Mz...etc";
  List<HttpMessageConverter> converters = new ArrayList<>(1);
  converters.add(new ByteArrayHttpMessageConverter());
  restTemplate.setMessageConverters(converters);
  HttpEntity<byte[]> request = new HttpEntity<byte[]>(null, getHeaders(true, "GET", null, canonicalPath, sessionId));
  //getHeaders() will return HttpHeaders with those parameter

  ResponseEntity<byte[]> response = null;
  try {
    response = this.restTemplate.exchange(uri, HttpMethod.GET, request, byte[].class);
  } catch( HttpServerErrorException hse ){
    throw hse;
  }
  return response;
}

更多信息可以在这里找到:https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/web/client/RestTemplate.html#setMessageConverters-java.util.List-在这里https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/http/converter/HttpMessageConverter.html在这里https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/http/converter/ByteArrayHttpMessageConverter.html