java 如何在 spring 中将图像转换为多部分文件
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How to convert Image to multipart file in spring
提问by subbu royal
I have an image file and creating Fileobject with that image
我有一个图像文件并File使用该图像创建对象
File file = new File("E://Shared Data/Images/xyz.jpg");
File file = new File("E://Shared Data/Images/xyz.jpg");
The above line is creating a fileobject with some size like 440272, I need to convert the above image fileinto multipart filefor that I did
上面的行正在创建一个file具有某种大小的对象440272，我需要将上面的内容image file转换multipart file为我所做的
DiskFileItem fileItem = new DiskFileItem("file", "image/png", false, file.getName(),
(int) file.length(), file.getParentFile());
fileItem.getOutputStream();
MultipartFile multipartFile = new CommonsMultipartFile(fileItem);
adminAssetUploadController.upload(request, multipartFile, "product", null);
the problem is after converting I am getting size=0instead of getting some sizelike 440272. If I get sizefor the imageso that I can store into some some location by passing it to uploadmethod.
问题是在转换后我得到size=0而不是得到一些size像440272. 如果我得到size了，image这样我就可以通过将它传递给upload方法来存储到某个位置。
below is the upload method
下面是上传方法
public ResponseEntity<Map<String, Object>> upload(HttpServletRequest request,
@RequestParam("file") MultipartFile file, @PathVariable(value = "sectionKey") String sectionKey,
@PathVariable(value = "id") String id) throws IOException {
Map<String, Object> responseMap = new HashMap<String, Object>();
Map<String, String> properties = new HashMap<String, String>();
properties.put("entityType", sectionKey);
properties.put("entityId", id);
StaticAsset staticAsset = staticAssetService.createStaticAssetFromFile(file, properties);
staticAssetStorageService.createStaticAssetStorageFromFile(file, staticAsset);
........
.......
}
can anyone help me why I am getting zero sizeafter converting into multipart fileis my approach is correct to convert image fileto multipart file? or I need to follow any other approachfor this?
谁能帮我为什么我收到zero size转换成后multipart file是我的做法是正确的转换image file来multipart file？或者我需要为此关注任何其他人approach？
采纳答案by Periklis Douvitsas
I would suggest convert the image by using this code
我建议使用此代码转换图像
FileInputStream input = new FileInputStream(fileItem);
MultipartFile multipartFile = new MockMultipartFile("fileItem",
fileItem.getName(), "image/png", IOUtils.toByteArray(input));
If you would like to use CommonsMultipartFile, I think you should have into your pom file the commons-fileupload
如果你想使用 CommonsMultipartFile，我认为你应该在你的 pom 文件中加入 commons-fileupload
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.3</version>
</dependency>
The documentation of CommonsMultipartFile states that
CommonsMultipartFile 的文档指出
NOTE: As of Spring 2.0, this class requires Commons FileUpload 1.1 or higher. The implementation does not use any deprecated FileUpload 1.0 API anymore, to be compatible with future Commons FileUpload releases. http://docs.spring.io/spring-framework/docs/2.0.8/api/org/springframework/web/multipart/commons/CommonsMultipartFile.html
注意：从 Spring 2.0 开始，此类需要 Commons FileUpload 1.1 或更高版本。该实现不再使用任何已弃用的 FileUpload 1.0 API，以与未来的 Commons FileUpload 版本兼容。 http://docs.spring.io/spring-framework/docs/2.0.8/api/org/springframework/web/multipart/commons/CommonsMultipartFile.html
Let me know if this worked for you
让我知道这是否对你有用
