public class FileUtil {
  private String filePath;
  private SimpleDateFormat sdf;

  public FileUtil() {
    sdf = new SimpleDateFormat("yyyy-MM-dd");
    filePath = "C:" + File.separator + "files" + File.separator + sdf.format(System.currentTimeMillis());
  }


  public List<AttachFile> fileSave(Collection<Part> parts) {
    File f = new File(filePath);
    List<AttachFile> attachFileList = new ArrayList<>();
    if (!f.exists()) {
      f.mkdirs();
    }
    for (Part part : parts) {
      String originalName = part.getSubmittedFileName();
      String saveFileName = UUID.randomUUID().toString().substring(0, 8) + "_" + originalName;
      if (part.getSubmittedFileName() != null) {
        try {
          part.write(f.getAbsolutePath() + File.separator + saveFileName);
          attachFileList.add(new AttachFile(originalName, saveFileName, f.getAbsolutePath()));
        } catch (IOException ie) {
          ie.printStackTrace();
        }
      }
    }
    return attachFileList;
  }

}

The file is stored in a path outside the context root. After adding or updating a file, the file name and path are stored in the database, and I confirmed that the file is written in the specified path. However, when I go into the post, I cannot load the file information from the database using the post’s primary key (pk). But if I turn off and then restart the server, I can properly load it through the post’s pk. I don’t know why. Please help.

I want to immediately check the added attachment by retrieving file information from the database using the post’s primary key (PK) after writing or editing a post.