@After
 public final void stopDatabase() {
   if (dbConnector != null) {
     dbConnector.stop();
     session.stop();
   }
 }
  @Before
  public final void startDatabase() throws Exception {
    if (dbConnector == null) {
      dbConnector = new MemoryDatabaseConnector();
      dbConnector.start();
      session = new JpaDatabaseSession(dbConnector);
      session.start();
    }

    databaseTester =
        new JdbcDatabaseTester(
            MemoryDatabaseConnector.DRIVER,
            MemoryDatabaseConnector.URL,
            MemoryDatabaseConnector.USER,
            MemoryDatabaseConnector.PASSWORD);
    databaseTester.onTearDown();
  }