java - 覆盖 png 文件

Question

我想覆盖上传的文件。我尝试了这段代码:

@PostMapping(value = "/upload", produces = { MediaType.APPLICATION_JSON_VALUE })
public ResponseEntity<String> uploadFile(@RequestParam("file") MultipartFile file,
        RedirectAttributes redirectAttributes, @RequestParam("id") Integer merchantId) throws Exception {
    try {
        File directory = new File(properties.getFileUploadDir(), merchantId.toString());
        directory.mkdirs();
        Path writeTargetPath = Files.write(
                Paths.get(directory.getAbsolutePath(), file.getOriginalFilename()).toAbsolutePath(),
                file.getBytes(), StandardOpenOption.CREATE_NEW);
        Path fileToMovePath = Paths.get(properties.getFileUploadDir(), merchantId.toString(), "merchant_logo.png");
        Path movedPath = Files.move(writeTargetPath, fileToMovePath, StandardCopyOption.REPLACE_EXISTING);
        log.info("movedPath: {}", movedPath.toAbsolutePath());

        redirectAttributes.addFlashAttribute("message",
                "Successfully uploaded '" + file.getOriginalFilename() + "'");
    } catch (IOException e) {
        log.error("IOException: {}", e);
        return ResponseEntity.ok("Upload failed'" + file.getOriginalFilename() + "'");
    }
    return ResponseEntity.ok("Successfully uploaded'" + file.getOriginalFilename() + "'");

}

但我收到错误:

java.nio.file.FileAlreadyExistsException: /opt/1/download.png

你知道如何在每次上传文件时覆盖同名的旧文件吗？

Answer 1

API documentation StandardOpenOption.CREATE_NEW 说:

Create a new file, failing if the file already exists.

将 StandardOpenOption.CREATE 与 StandardOpenOption.TRUNCATE_EXISTING 结合使用:

Path writeTargetPath = Files.write(
    Paths.get(directory.getAbsolutePath(), file.getOriginalFilename()).toAbsolutePath(),
    file.getBytes(), StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING);