code: private boolean forceLoad(PropertyData prop)
     {
        final List<ValueData> vals = prop.getValues();
        for (int i = 0; i < vals.size(); i++)
        {
           ValueData vd = vals.get(i);
           if (!vd.isByteArray())
           {
              // check if file is correct
              FilePersistedValueData fpvd = (FilePersistedValueData)vd;
              if (fpvd.getFile() == null)
              {
                 if (fpvd instanceof StreamPersistedValueData && ((StreamPersistedValueData)fpvd).getUrl() != null)
                    continue;
                 return true;
              }
              else if (!PrivilegedFileHelper.exists(fpvd.getFile()))// check if file exist
              {
                 return true;
              }
           }
        }
        return false;
     }
docs: Check Property BLOB Values if someone has null file.
  
  @param prop PropertyData
  @throws RepositoryException
  @return <code>true</code> if the Property BLOB Values has null file, <code>false</code> otherwise.