Springboot实现PDF图片上传到服务器并保存路径到数据库

可以使用Apache PDFBox和Spring Boot的MultipartFile类来实现PDF图片上传到服务器并保存路径到数据库。首先，使用MultipartFile类将PDF文件上传到服务器上的指定目录。然后，使用Apache PDFBox将PDF文件转换为图片，并将图片保存到服务器上的指定目录。最后，将图片路径保存到数据库中。以下是示例代码：

@PostMapping("/uploadPDF")
public String uploadPDF(@RequestParam("file") MultipartFile file) {
    String fileName = StringUtils.cleanPath(file.getOriginalFilename());
    String uploadDir = "pdf_uploads";
    String filePath = uploadDir + "/" + fileName;
    try {
        FileUploadUtil.saveFile(uploadDir, fileName, file);
        PDDocument document = PDDocument.load(new File(filePath));
        PDFRenderer pdfRenderer = new PDFRenderer(document);
        BufferedImage bim = pdfRenderer.renderImageWithDPI(0, 300, ImageType.RGB);
        String imageDir = "image_uploads";
        String imageName = FilenameUtils.getBaseName(fileName) + ".png";
        String imagePath = imageDir + "/" + imageName;
        FileUploadUtil.saveImage(imageDir, imageName, bim);
        document.close();
        // 将图片路径保存到数据库中
        // ...
        return "File uploaded successfully!";
    } catch (IOException e) {
        e.printStackTrace();
        return "Failed to upload file!";
    }
}

其中，FileUploadUtil是一个工具类，用于保存文件和图片到指定目录：

public class FileUploadUtil {
    public static void saveFile(String uploadDir, String fileName, MultipartFile file) throws IOException {
        Path uploadPath = Paths.get(uploadDir);
        if (!Files.exists(uploadPath)) {
            Files.createDirectories(uploadPath);
        }
        try (InputStream inputStream = file.getInputStream()) {
            Path filePath = uploadPath.resolve(fileName);
            Files.copy(inputStream, filePath, StandardCopyOption.REPLACE_EXISTING);
        } catch (IOException e) {
            throw new IOException("Could not save file: " + fileName, e);
        }
    }

    public static void saveImage(String uploadDir, String imageName, BufferedImage image) throws IOException {
        Path uploadPath = Paths.get(uploadDir);
        if (!Files.exists(uploadPath)) {
            Files.createDirectories(uploadPath);
        }
        Path imagePath = uploadPath.resolve(imageName);
        ImageIO.write(image, "png", imagePath.toFile());
    }
}