如何在Java/Spring中以blob/byte的形式下载文件

import org.springframework.core.io.ByteArrayResource;
import org.springframework.core.io.Resource;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;

// 定义下载文件的Controller
@RestController
public class FileDownloadController {

    @GetMapping("/download")
    public ResponseEntity<Resource> downloadFile() throws IOException {
        // 获取文件的路径和文件名
        String filePath = "/path/to/file";
        String fileName = "example.txt";
        
        // 读取文件为字节数组
        File file = new File(filePath);
        byte[] fileContent = Files.readAllBytes(file.toPath());

        // 创建响应体，将字节数组作为内容
        ByteArrayResource resource = new ByteArrayResource(fileContent);

        // 设置响应头
        HttpHeaders headers = new HttpHeaders();
        headers.add(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=" + fileName);
        headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);

        // 返回响应对象
        return ResponseEntity.ok()
                .headers(headers)
                .body(resource);
    }
}