Question

我使用的是localhost：8080 / _ah / api / explorer google explore：我一直在

{
 "error": {
  "message": "com.google.appengine.repackaged.org.codehaus.jackson.map.JsonMappingException: Can not construct instance of javax.servlet.http.HttpServletResponse, problem: abstract types can only be instantiated with additional type information\n at [Source: N/A; line: -1, column: -1]",
  "code": 400,
  "errors": [
   {
    "domain": "global",
    "reason": "badRequest",
    "message": "com.google.appengine.repackaged.org.codehaus.jackson.map.JsonMappingException: Can not construct instance of javax.servlet.http.HttpServletResponse, problem: abstract types can only be instantiated with additional type information\n at [Source: N/A; line: -1, column: -1]"
   }
  ]
 }

我的Google SPI代码是：

    @ApiMethod(name = "findBillImage", httpMethod = ApiMethod.HttpMethod.GET )
public void findImage(HttpServletResponse httpServletResponse ,  @Named("blobkey") String blobKeyValue)   throws IOException {
     BlobKey blobKey = new BlobKey( blobKeyValue );
     BlobstoreService blobstoreService = BlobstoreServiceFactory.getBlobstoreService();          
     blobstoreService.serve(blobKey, httpServletResponse);       
}

任何时候我试图向HttpServletResponse写任何东西我得到这个错误..我迷失了为什么我不能写入httpServletResponse

Answer 1

SOOOO .. 答案真的是设计＆＃39;就我而言。

因为我是实施＆＃34; REST＆＃34;使用谷歌应用引擎......我不应该修改HttpResponse来返回＆＃34;图像＆＃34;。

所以＆＃34;服务＆＃34;回到HttpResponse的图像并不理想。我应该直接用存储URL将图像暴露给客户端。：

https://storage.cloud.google.com/myapp.appspot.com/20160603_154924.jpg

不能说我100％＆＃39;喜欢这个答案，但从我正在阅读的内容来看，我认为这是正确的。

java BlobStore和Google SPI AppEngine端点

1 个答案: