springboot下载文件到项目路径下

可以使用以下代码实现：

@RestController
public class FileDownloadController {

    @GetMapping("/download")
    public ResponseEntity<Resource> downloadFile() throws IOException {
        String filename = "example.txt";
        File file = new File(filename);
        Path path = Paths.get(file.getAbsolutePath());
        ByteArrayResource resource = new ByteArrayResource(Files.readAllBytes(path));
        HttpHeaders headers = new HttpHeaders();
        headers.add(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=" + filename);
        return ResponseEntity.ok()
                .headers(headers)
                .contentLength(file.length())
                .contentType(MediaType.APPLICATION_OCTET_STREAM)
                .body(resource);
    }
}

这个代码片段可以将名为 "example.txt" 的文件下载到项目路径下。