nl.knaw.huygens.timbuctoo.graph.Graph.java Source code

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Here is the source code for nl.knaw.huygens.timbuctoo.graph.Graph.java

Source

package nl.knaw.huygens.timbuctoo.graph;

/*
 * #%L
 * Timbuctoo core
 * =======
 * Copyright (C) 2012 - 2015 Huygens ING
 * =======
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public 
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/gpl-3.0.html>.
 * #L%
 */

import java.util.Collection;
import java.util.Map;

import com.google.common.collect.Maps;

public class Graph {

    private final Map<String, Vertex> vertices;

    public Graph() {
        vertices = Maps.newTreeMap();
    }

    public int numberOfVertices() {
        return vertices.size();
    }

    public Collection<Vertex> getVertices() {
        return vertices.values();
    }

    /**
     * Returns the vertex with the specified name, or create a new
     * one if it does not yet exist.
     * @param name the name of the vertex.
     * @return the vertex.
     */
    private Vertex getVertex(String name) {
        Vertex vertex = vertices.get(name);
        if (vertex == null) {
            vertex = new Vertex(name);
            vertices.put(name, vertex);
        }
        return vertex;
    }

    public void addVertex(String name) {
        getVertex(name);
    }

    private Edge getEdge(String srce, String dest) {
        Vertex s = getVertex(srce);
        Vertex d = getVertex(dest);
        return s.getEdgeTo(d);
    }

    public void addWeightToEdge(String srce, String dest, int weight) {
        Edge edge = getEdge(srce, dest);
        edge.addToWeight(weight);
    }

    @Override
    public String toString() {
        StringBuilder builder = new StringBuilder();

        Map<String, Integer> map = Maps.newHashMap();
        builder.append(String.format("*Nodes%n"));
        builder.append(String.format("id*int label*string%n"));
        int index = 0;
        for (Vertex vertex : getVertices()) {
            index++;
            map.put(vertex.getName(), index);
            builder.append(String.format("%d\t%s%n", index, vertex.getName()));
        }

        builder.append(String.format("*DirectedEdges%n"));
        builder.append(String.format("source*int target*int weight*int%n"));
        for (Vertex vertex : getVertices()) {
            int source = map.get(vertex.getName());
            for (Edge edge : vertex.getEdges()) {
                int target = map.get(edge.getDestVertex().getName());
                builder.append(String.format("%d\t%d\t%d%n", source, target, edge.getWeight()));
            }
        }

        return builder.toString();
    }

    public static void main(String[] args) {
        Graph graph = new Graph();
        graph.addWeightToEdge("a", "b", 1);
        graph.addWeightToEdge("a", "c", 2);
        graph.addWeightToEdge("a", "d", 3);
        graph.addWeightToEdge("c", "b", 2);
        graph.addWeightToEdge("a", "b", 5);
        System.out.println(graph);
    }

}