org.jgrapht.opt.graph.fastutil.FastutilFastLookupIntVertexGSS Maven / Gradle / Ivy
/*
* (C) Copyright 2018-2023, by Dimitrios Michail and Contributors.
*
* JGraphT : a free Java graph-theory library
*
* See the CONTRIBUTORS.md file distributed with this work for additional
* information regarding copyright ownership.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License 2.0 which is available at
* http://www.eclipse.org/legal/epl-2.0, or the
* GNU Lesser General Public License v2.1 or later
* which is available at
* http://www.gnu.org/licenses/old-licenses/lgpl-2.1-standalone.html.
*
* SPDX-License-Identifier: EPL-2.0 OR LGPL-2.1-or-later
*/
package org.jgrapht.opt.graph.fastutil;
import it.unimi.dsi.fastutil.ints.*;
import it.unimi.dsi.fastutil.objects.*;
import org.jgrapht.*;
import org.jgrapht.graph.*;
import org.jgrapht.graph.specifics.*;
import java.io.*;
import java.util.function.*;
/**
* A specifics strategy implementation using fastutil maps for storage specialized for integer
* vertices.
*
*
* Graphs constructed using this strategy use additional data structures to improve the performance
* of methods which depend on edge retrievals, e.g. getEdge(V u, V v), containsEdge(V u, V
* v),addEdge(V u, V v). A disadvantage is an increase in memory consumption. If memory utilization
* is an issue, use the {@link FastutilIntVertexGSS} instead.
*
* @author Dimitrios Michail
*
* @param the graph edge type
*/
public class FastutilFastLookupIntVertexGSS
implements
GraphSpecificsStrategy
{
private static final long serialVersionUID = 6098261533235930603L;
@Override
public BiFunction, GraphType, Specifics> getSpecificsFactory()
{
return (BiFunction, GraphType,
Specifics> & Serializable) (graph, type) -> {
if (type.isDirected()) {
return new FastLookupDirectedSpecifics<>(
graph, new Int2ReferenceLinkedOpenHashMap<>(),
new Object2ObjectOpenHashMap<>(), getEdgeSetFactory());
} else {
return new FastLookupUndirectedSpecifics<>(
graph, new Int2ReferenceLinkedOpenHashMap<>(),
new Object2ObjectOpenHashMap<>(), getEdgeSetFactory());
}
};
}
@Override
public Function> getIntrusiveEdgesSpecificsFactory()
{
return (Function> & Serializable) (type) -> {
if (type.isWeighted()) {
return new WeightedIntrusiveEdgesSpecifics(
new Object2ObjectLinkedOpenHashMap<>());
} else {
return new UniformIntrusiveEdgesSpecifics<>(new Object2ObjectLinkedOpenHashMap<>());
}
};
}
}