Uploaded GIF image doesn't move

Question

I made multiple image uploading code in Java. It will resize image if it's too big.

Everything seems to work fine, but uploaded .gif files do not move.

I think I mixed multipartFile and imageIO. It also seems like contenttype code has a problem.

I don't know where to fix.

public class FileHandler {

    private static final int MAX_WIDTH = 780;
    private static final int MAX_HEIGHT = 1000;

    public List<ImageModel> parseFileInfo(String boardType, List<MultipartFile> multipartFiles) throws Exception {

        List<ImageModel> fileList = new ArrayList<>();

        if (multipartFiles.isEmpty()) {
            return fileList;
        }

        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyyMMdd");
        String current_date = simpleDateFormat.format(new Date());

        String absolutePath = new File("").getAbsolutePath() + "\\src\\main\\";

        String path = "uploads/images/" + boardType + "/" + current_date;
        File file = new File(absolutePath + path);
        if (!file.exists()) {
            file.mkdirs();
        }

        for (MultipartFile multipartFile : multipartFiles) {
            if (!multipartFile.isEmpty()) {

                BufferedImage originalImage = ImageIO.read(multipartFile.getInputStream());
                int contentType = originalImage.getType() == 0 ? BufferedImage.TYPE_INT_ARGB : originalImage.getType();
                String[] originalName = multipartFile.getOriginalFilename().split("\\.");
                String Type = originalName[1];
                int width = originalImage.getWidth();
                int height = originalImage.getHeight();

                Dimension imgSize = new Dimension(width, height); 
                Dimension boundary = new Dimension(MAX_WIDTH, MAX_HEIGHT); 
                Dimension newImgSize = getScaledDimension(imgSize, boundary); 

                Image resizedImage = originalImage.getScaledInstance(newImgSize.width, newImgSize.height, Image.SCALE_SMOOTH); 

                BufferedImage newImage = new BufferedImage(newImgSize.width, newImgSize.height, BufferedImage.TYPE_INT_BGR);
                Graphics graphics = newImage.getGraphics();
                graphics.drawImage(resizedImage, 0, 0, null);
                graphics.dispose();

                String new_file_name = System.nanoTime() + "." + Type;

                file = new File(absolutePath + path + "/" + new_file_name);
                try{
                    ImageIO.write(newImage, Type, file);
                }catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
        }

        return fileList;
    }
}