@Override
  public void start() {
    File dbHome = new File(getRequiredSetting(PATH_DATA.getKey()));
    if (!dbHome.exists()) {
      dbHome.mkdirs();
    }

    startServer(dbHome);
  }
@Test
  public void start_ignores_URL_to_create_database_and_uses_empty_username_and_password_when_then_are_not_set() throws IOException {
    int port = NetworkUtilsImpl.INSTANCE.getNextLoopbackAvailablePort();
    settings
      .setProperty(PATH_DATA.getKey(), temporaryFolder.newFolder().getAbsolutePath())
      .setProperty(JDBC_URL.getKey(), "jdbc url")
      .setProperty(JDBC_EMBEDDED_PORT.getKey(), "" + port);

    underTest.start();

    checkDbIsUp(port, "", "");
  }