content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.datastax.dse.driver.internal.core.graph;
  
  import com.datastax.dse.driver.api.core.graph.AsyncGraphResultSet;
  import com.datastax.dse.driver.api.core.graph.GraphNode;
  import java.util.Iterator;
  import java.util.NoSuchElementException;
  import net.jcip.annotations.NotThreadSafe;
  import org.apache.tinkerpop.gremlin.process.remote.traversal.AbstractRemoteTraversal;
  import org.apache.tinkerpop.gremlin.process.remote.traversal.DefaultRemoteTraverser;
  import org.apache.tinkerpop.gremlin.process.traversal.Traverser;
  
  @NotThreadSafe
  class DseGraphTraversal<S, E> extends AbstractRemoteTraversal<S, E> {
  
    private final Iterator<GraphNode> graphNodeIterator;
  
    public DseGraphTraversal(AsyncGraphResultSet firstPage) {
      this.graphNodeIterator = GraphResultSets.toSync(firstPage).iterator();
    }
  
    @Override
    public boolean hasNext() {
      return graphNodeIterator.hasNext();
    }
  
    @Override
    public E next() {
      return nextTraverser().get();
    }
  
    @Override
    @SuppressWarnings("unchecked")
    public Traverser.Admin<E> nextTraverser() {
      if (hasNext()) {
        GraphNode nextGraphNode = graphNodeIterator.next();
  
        // get the Raw object from the ObjectGraphNode, create a new remote Traverser
        // with bulk = 1 because bulk is not supported yet. Casting should be ok
        // because we have been able to deserialize into the right type.
        return new DefaultRemoteTraverser<>((E) nextGraphNode.as(Object.class), 1);
      } else {
        // finished iterating/nothing to iterate. Normal behaviour.
        throw new NoSuchElementException();
      }
    }
  }
  