Question

package edu.uci.ics.jung.algorithms.cluster;

import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.apache.commons.collections15.Transformer;

import edu.uci.ics.jung.algorithms.scoring.BetweennessCentrality;
import edu.uci.ics.jung.graph.Graph;
import edu.uci.ics.jung.graph.util.Pair;

    public class EdgeBetweennessClusterer<V, E> implements
        Transformer<Graph<V, E>, Set<Set<V>>> {
    private int mNumEdgesToRemove;
    private Map<E, Pair<V>> edges_removed;


    public EdgeBetweennessClusterer(int numEdgesToRemove) {
        mNumEdgesToRemove = numEdgesToRemove;
        edges_removed = new LinkedHashMap<E, Pair<V>>();


    }
      public Set<Set<V>> transform(Graph<V, E> graph) {

        if (mNumEdgesToRemove < 0
                || mNumEdgesToRemove > graph.getEdgeCount()) {
            throw new IllegalArgumentException(
                    "Invalid number of edges passed in.");
        }

        edges_removed.clear();

        for (int k = 0; k < mNumEdgesToRemove; k++) {
            BetweennessCentrality<V, E> bc = new BetweennessCentrality<V, E>(
                    graph);
            E to_remove = null;
            double score = 0;
            for (E e : graph.getEdges())
                if (bc.getEdgeScore(e) > score) {
                    to_remove = e;
                    score = bc.getEdgeScore(e);
                }
            edges_removed.put(to_remove, graph.getEndpoints(to_remove));
            graph.removeEdge(to_remove);
        }

        WeakComponentClusterer<V, E> wcSearch = new WeakComponentClusterer<V, E>();
        Set<Set<V>> clusterSet = wcSearch.transform(graph);

        for (Map.Entry<E, Pair<V>> entry : edges_removed.entrySet()) {
            Pair<V> endpoints = entry.getValue();
            graph.addEdge(entry.getKey(), endpoints.getFirst(),
                    endpoints.getSecond());
        }
        Object array[];
        array=new Object[500];
        array=clusterSet.toArray();
        System.out.println(array.length);
        for(int i=0;i<array.length;i++)

        {
            System.out.println("hello");
            System.out.println("hkj"+array[i]);
        }
        return clusterSet;
    }

    /**
     * Retrieves the list of all edges that were removed
     * (assuming extract(...) was previously called). 
     * The edges returned
     * are stored in order in which they were removed.
     *
     * @return the edges in the original graph
     */
    public List<E> getEdgesRemoved() {
        return new ArrayList<E>(edges_removed.keySet());
    }


    public static void main(String args[])
    {
        new EdgeBetweennessClusterer(10);
    }
}

This algorithm is copied from here

I am making network based community so I used this algorithm
when I am running this code, the main method, and is not getting called. I am not able to understand what is happening. Correct me if I am wrong. What mistake am I making?

Answer 1

If you remove all the code which doesn’t do anything your program is the same as

public EdgeBetweennessClusterer(int numEdgesToRemove) {
    mNumEdgesToRemove = numEdgesToRemove;
    edges_removed = new LinkedHashMap<E, Pair<V>>();
}

public static void main(String args[]) {
    new EdgeBetweennessClusterer(10);
}

If you want your program to call more code, you need to tell it to do so. Perhaps using a debugger will help you see what your program is doing any why.