code: public long getLastModified(String path)
    {
      try {
        // this entry time can cause problems ...
        ZipEntry entry = getZipEntry(path);
  
        return entry != null ? entry.getTime() : -1;
      } catch (IOException e) {
        log.log(Level.FINE, e.toString(), e);
      }
  
      return  -1;
    }
docs: Returns the last-modified time of the entry in the jar file.
  
  @param path full path to the jar entry
  @return the length of the entry