org.opennms.features.topology.app.internal.jung.FRLayoutAlgorithm.java Source code

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Here is the source code for org.opennms.features.topology.app.internal.jung.FRLayoutAlgorithm.java

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/*******************************************************************************
 * This file is part of OpenNMS(R).
 *
 * Copyright (C) 2012-2014 The OpenNMS Group, Inc.
 * OpenNMS(R) is Copyright (C) 1999-2014 The OpenNMS Group, Inc.
 *
 * OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc.
 *
 * OpenNMS(R) 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.
 *
 * OpenNMS(R) 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 OpenNMS(R).  If not, see:
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 *
 * For more information contact:
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package org.opennms.features.topology.app.internal.jung;

import java.awt.Dimension;
import java.awt.geom.Point2D;
import java.util.Collection;

import edu.uci.ics.jung.algorithms.layout.FRLayout;
import edu.uci.ics.jung.graph.SparseGraph;
import org.apache.commons.collections15.Transformer;
import org.opennms.features.topology.api.Graph;
import org.opennms.features.topology.api.GraphContainer;
import org.opennms.features.topology.api.Layout;
import org.opennms.features.topology.api.Point;
import org.opennms.features.topology.api.topo.Edge;
import org.opennms.features.topology.api.topo.EdgeRef;
import org.opennms.features.topology.api.topo.Vertex;
import org.opennms.features.topology.api.topo.VertexRef;

public class FRLayoutAlgorithm extends AbstractLayoutAlgorithm {

    @Override
    public void updateLayout(final GraphContainer graphContainer) {

        Graph g = graphContainer.getGraph();

        final Layout graphLayout = g.getLayout();

        SparseGraph<VertexRef, EdgeRef> jungGraph = new SparseGraph<VertexRef, EdgeRef>();

        Collection<Vertex> vertices = g.getDisplayVertices();

        for (Vertex v : vertices) {
            jungGraph.addVertex(v);
        }

        Collection<Edge> edges = g.getDisplayEdges();

        for (Edge e : edges) {
            jungGraph.addEdge(e, e.getSource().getVertex(), e.getTarget().getVertex());
        }

        FRLayout<VertexRef, EdgeRef> layout = new FRLayout<VertexRef, EdgeRef>(jungGraph);
        // Initialize the vertex positions to the last known positions from the layout
        Dimension size = selectLayoutSize(graphContainer);
        layout.setInitializer(initializer(graphLayout, (int) size.getWidth() / 2, (int) size.getHeight() / 2));
        // Resize the graph to accommodate the number of vertices
        layout.setSize(size);

        while (!layout.done()) {
            layout.step();
        }

        // Store the new positions in the layout
        for (Vertex v : vertices) {
            graphLayout.setLocation(v, new Point(layout.getX(v) - (size.getWidth() / 2),
                    (int) layout.getY(v) - (size.getHeight() / 2)));
        }
    }

    protected static Transformer<VertexRef, Point2D> initializer(final Layout graphLayout, final int xOffset,
            final int yOffset) {
        return new Transformer<VertexRef, Point2D>() {
            @Override
            public Point2D transform(VertexRef v) {
                org.opennms.features.topology.api.Point location = graphLayout.getLocation(v);
                return new Point2D.Double(location.getX() + xOffset, location.getY() + yOffset);
            }
        };
    }
}