@Override
        protected void initializeImplementation() {
            // no init required
            if (close.isDone()) {
                throw new IllegalStateException("Client is closed");
            } else if (cluster.availableHosts().isEmpty()) {
                throw new NoHostAvailableException();
            }
        }
Uses a {@link Client.ClusteredClient} that rebinds requests to a specified {@link Graph} or
{@link TraversalSource} instances on the server-side.
gremlin-driver/src/main/java/org/apache/tinkerpop/gremlin/driver/Client.java