code: public void restart() {
          lock.writeLock().lock();
          try {
              if (this.timeoutTask == null) {
                  throw new IllegalStateException(Tr.formatMessage(tc, "internal.error.CWMFT4999E"));
              }
              stop();
              this.stopped = false;
              start(this.timeoutTask);
          } finally {
              lock.writeLock().unlock();
          }
      }
docs: Restart the timer ... stop the timer, reset the stopped flag and then start again with the same timeout policy