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* Licensed to the Apache Software Foundation (ASF) under one
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* 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,
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* See the License for the specific language governing permissions and
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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 extends AbstractRemoteTraversal {
private final Iterator 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 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();
}
}
}