code: public long lastModified(final File file) {
          if (System.getSecurityManager() == null)
              return file.lastModified();
          return AccessController.doPrivileged(new PrivilegedAction<Long>() {
              @Override
              public Long run() {
                  return new Long(file.lastModified());
              }
          }, controlContext).longValue();
      }
docs: Returns a file's last modified stamp. Same as calling
  file.lastModified().
  
  @param file a file object
  @return a file's last modified stamp.