java保存文件，Java文件名生成

File file = new File("D:\\safeDoc");
        String fileName= vo.getUploadFileName();
        String uploadFileName = vo.getPictureType()+UUID.randomUUID().toString().replace("-", "")+fileName.substring(fileName.lastIndexOf(".") );
        try {
            FileUtils.copyFile(vo.getUpload(), new File(file,uploadFileName));
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }