/*
* SonarQube, open source software quality management tool.
* Copyright (C) 2008-2014 SonarSource
* mailto:contact AT sonarsource DOT com
*
* SonarQube is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* SonarQube 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package org.sonar.core.graph;
import com.google.common.collect.Sets;
import com.tinkerpop.blueprints.Direction;
import com.tinkerpop.blueprints.Edge;
import com.tinkerpop.blueprints.Graph;
import com.tinkerpop.blueprints.Vertex;
import com.tinkerpop.blueprints.impls.tg.TinkerGraph;
import com.tinkerpop.blueprints.util.ElementHelper;
import java.util.List;
import java.util.Set;
/**
* Not thread-safe
*/
public class SubGraph {
private TinkerGraph sub = new TinkerGraph();
private Set<Edge> edgesToCopy = Sets.newHashSet();
private SubGraph() {
}
public static Graph extract(Vertex start, EdgePath edgePath) {
return new SubGraph().process(start, edgePath);
}
private Graph process(Vertex start, EdgePath edgePath) {
copy(start);
browse(start, 0, edgePath.getElements());
for (Edge edge : edgesToCopy) {
Vertex from = edge.getVertex(Direction.OUT);
Vertex to = edge.getVertex(Direction.IN);
Edge copyEdge = sub.addEdge(edge.getId(), sub.getVertex(from.getId()), sub.getVertex(to.getId()), edge.getLabel());
ElementHelper.copyProperties(edge, copyEdge);
}
return sub;
}
private void browse(Vertex from, int cursor, List<Object> edgePath) {
if (from != null && cursor < edgePath.size()) {
Direction edgeDirection = (Direction) edgePath.get(cursor);
String edgeLabel = (String) edgePath.get(cursor + 1);
Iterable<Edge> edges = from.getEdges(edgeDirection, edgeLabel);
for (Edge edge : edges) {
edgesToCopy.add(edge);
Vertex tail = edge.getVertex(edgeDirection.opposite());
copy(tail);
browse(tail, cursor + 2, edgePath);
}
}
}
private Vertex copy(Vertex v) {
Vertex to = sub.getVertex(v.getId());
if (to == null) {
to = sub.addVertex(v.getId());
ElementHelper.copyProperties(v, to);
}
return to;
}
}