public synchronized Client init() {
        if (initialized)
            return this;

        logger.debug("Initializing client on cluster [{}]", cluster);

        cluster.init();

        initializeImplementation();

        initialized = true;
        return this;
    }
Initializes the client which typically means that a connection is established to the server.  Depending on the
implementation and configuration this blocking call may take some time.  This method will be called
automatically if it is not called directly and multiple calls will not have effect.
gremlin-driver/src/main/java/org/apache/tinkerpop/gremlin/driver/Client.java