code: @Nullable
    public String getWaitingLockString(final ThreadInfo threadInfo) {
      if (null == threadInfo.getLockInfo()) {
        return null;
      } else {
        return threadInfo.getLockName() + " held by " + threadInfo.getLockOwnerName();
      }
    }
docs: Get a string identifying the lock that this thread is waiting on.
  @param threadInfo
  @return A string identifying the lock that this thread is waiting on,
  or null if the thread is not waiting on a lock