com.vertixtech.antiquity.graph.VersionedEdgeIterable.java Source code

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Here is the source code for com.vertixtech.antiquity.graph.VersionedEdgeIterable.java

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/**
 * Copyright (c) 2012-2013 "Vertix Technologies, ltd."
 *
 * This file is part of Antiquity.
 *
 * Antiquity is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
package com.vertixtech.antiquity.graph;

import java.util.Iterator;
import java.util.List;

import com.google.common.collect.Iterables;
import com.tinkerpop.blueprints.CloseableIterable;
import com.tinkerpop.blueprints.Edge;
import com.tinkerpop.blueprints.util.wrappers.event.EventTrigger;
import com.tinkerpop.blueprints.util.wrappers.event.listener.GraphChangedListener;

/**
 * A sequence of edges that is filtered by validity according to the specified version
 */
class VersionedEdgeIterable<V extends Comparable<V>> implements CloseableIterable<Edge> {

    private final Iterable<Edge> iterable;
    private final List<GraphChangedListener> graphChangedListeners;
    private final EventTrigger trigger;
    private final VersionedGraph<?, V> graph;
    private final V version;

    public VersionedEdgeIterable(final Iterable<Edge> iterable,
            final List<GraphChangedListener> graphChangedListeners, final EventTrigger trigger,
            VersionedGraph<?, V> graph, V version) {
        this.iterable = iterable;
        this.graphChangedListeners = graphChangedListeners;
        this.trigger = trigger;
        this.graph = graph;
        this.version = version;
    }

    @Override
    public Iterator<Edge> iterator() {
        return new Iterator<Edge>() {
            private final Iterator<Edge> itty = Iterables
                    .filter(iterable, new VersionedVertexEdgePredicate<V>(graph, version)).iterator();

            @Override
            public void remove() {
                this.itty.remove();
            }

            @Override
            public Edge next() {
                Edge edge = this.itty.next();

                if (graph.isHistoricalOrInternal(edge)) {
                    return edge;
                } else {
                    return new VersionedEdge<V>(edge, graphChangedListeners, trigger, graph, version);
                }
            }

            @Override
            public boolean hasNext() {
                return this.itty.hasNext();
            }
        };
    }

    @Override
    public void close() {
        if (this.iterable instanceof CloseableIterable) {
            ((CloseableIterable<Edge>) this.iterable).close();
        }
    }
}