/** * Copyright (c) 2012-2014 "Indexia 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 co.indexia.antiquity.graph; import java.util.Iterator; import com.google.common.base.Preconditions; import com.tinkerpop.blueprints.CloseableIterable; import com.tinkerpop.blueprints.Edge; /** * A sequence of edges that wraps each edge as {@link ActiveVersionedEdge}. */ public class ActiveVersionedEdgeIterable<V extends Comparable<V>> implements CloseableIterable<Edge> { /** * The raw iterable retrieved from the underline blueprints graph. */ Iterable<Edge> rawIterable; /** * The associated graph instance. */ private final ActiveVersionedGraph<?, V> graph; /** * Creates an instance. * * @param rawIterable the raw iterable retrieved from the underline * blueprints graph. * @param graph the graph instance {@link this} associated with */ public ActiveVersionedEdgeIterable(Iterable<Edge> rawIterable, ActiveVersionedGraph<?, V> graph) { Preconditions.checkNotNull(rawIterable, "Raw iterable must be set."); Preconditions.checkNotNull(graph, "Graph must be set."); this.rawIterable = rawIterable; this.graph = graph; } @Override public void close() { if (rawIterable instanceof CloseableIterable) { ((CloseableIterable) rawIterable).close(); } } @Override public Iterator<Edge> iterator() { return new Iterator<Edge>() { private final Iterator<Edge> itty = rawIterable.iterator(); public void remove() { this.itty.remove(); } public Edge next() { Edge edge = this.itty.next(); graph.utils.ensureActiveType(edge); if (edge instanceof ActiveVersionedEdge) { // TODO: currently for safety, this condition may occur? if // so then why? return edge; } else { return new ActiveVersionedEdge<V>(edge, graph); } } public boolean hasNext() { return this.itty.hasNext(); } }; } }