graphs.Graphs.java Source code

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Here is the source code for graphs.Graphs.java

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package graphs;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Paint;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import javax.swing.JFrame;

import org.apache.commons.collections15.Transformer;

import edu.uci.ics.jung.algorithms.layout.*;
import edu.uci.ics.jung.graph.Graph;
import edu.uci.ics.jung.graph.SparseGraph;
import edu.uci.ics.jung.graph.SparseMultigraph;
import edu.uci.ics.jung.visualization.BasicVisualizationServer;
import edu.uci.ics.jung.visualization.decorators.ToStringLabeller;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.Queue;
import java.util.Set;

public class Graphs {

    public static void main(String[] args) {
        Graphs graph = new Graphs();
        Graph<String, Integer> graph1 = new SparseGraph<String, Integer>();
        graph1.addEdge(1, "A", "C");
        graph1.addEdge(6, "A", "F");
        graph1.addEdge(5, "B", "C");
        graph1.addEdge(10, "B", "Z");
        graph1.addEdge(3, "B", "D");
        graph1.addEdge(4, "D", "E");
        System.out.println("Original: vertices and edges");
        System.out.println(graph1);

        String path = BreadthSearch(graph1);
        System.out.println("print breadth first search path");
        System.out.println(path);

        Layout<String, Integer> layout = new CircleLayout<String, Integer>(graph1);
        BasicVisualizationServer<String, Integer> vv = new BasicVisualizationServer<String, Integer>(layout);

        vv.setPreferredSize(new Dimension(600, 600)); //Sets the viewing area size

        vv.getRenderContext().setVertexLabelTransformer(new ToStringLabeller());
        vv.getRenderContext().setEdgeLabelTransformer(new ToStringLabeller());

        JFrame frame = new JFrame("Simple Graph View");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().add(vv);
        frame.pack();
        frame.setVisible(true);

    }

    //Breadth first search - checks adj of start, adds to queue if it is unvisted, then adds to visited sequence
    public static <V, E> String BreadthSearch(Graph<V, E> g) {
        StringBuilder b = new StringBuilder();

        Queue<V> Qu = new LinkedList<V>();
        Set<V> visited = new HashSet();
        Set<V> found = new HashSet();

        V start = (V) g.getVertices().toArray()[0];
        Qu.add(start);
        found.add(start);

        while (!Qu.isEmpty()) {
            V vertex = Qu.remove();
            for (V neighbor : g.getNeighbors(vertex)) {
                if (!found.contains(neighbor) && !visited.contains(neighbor)) {
                    found.add(neighbor);
                    Qu.add(neighbor);
                }
            }
            b.append(vertex.toString() + " ");
            visited.add(vertex);
        }

        return b.toString();
    }
}