ConnectionNotDefinedException example

  final protected static function openConnection($key, $target) {
    // If the requested database does not exist then it is an unrecoverable     // error.     if (!isset(self::$databaseInfo[$key])) {
      throw new ConnectionNotDefinedException('The specified database connection is not defined: ' . $key);
    }

    if (!self::$databaseInfo[$key][$target]['driver']) {
      throw new DriverNotSpecifiedException('Driver not specified for this database connection: ' . $key);
    }

    $driver_class = self::$databaseInfo[$key][$target]['namespace'] . '\\Connection';

    $client_connection = $driver_class::open(self::$databaseInfo[$key][$target]);
    $new_connection = new $driver_class($client_connection, self::$databaseInfo[$key][$target]);
    $new_connection->setTarget($target);
    

'arguments' => [],
      'function' => 'ensureInnoDbAvailable',
    ];
  }

  /** * {@inheritdoc} */
  public function name() {
    try {
      if (!$this->isConnectionActive() || !$this->getConnection() instanceof Connection) {
        throw new ConnectionNotDefinedException('The database connection is not active or not a MySql connection');
      }
      if ($this->getConnection()->isMariaDb()) {
        return $this->t('MariaDB');
      }
      return $this->t('MySQL, Percona Server, or equivalent');
    }
    catch (ConnectionNotDefinedException $e) {
      return $this->t('MySQL, MariaDB, Percona Server, or equivalent');
    }
  }