TopologicalOrdering.java

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package edu.tum.cs.bayesnets.util;

import java.util.HashMap;
import java.util.NoSuchElementException;
import java.util.Random;
import java.util.Vector;

import edu.ksu.cis.bnj.ver3.core.BeliefNode;

public class TopologicalOrdering implements Iterable<Integer> {
        Vector<Vector<Integer>> partialOrder;
        HashMap<BeliefNode, Integer> tierMap;
        
        public TopologicalOrdering(Vector<Vector<Integer>> partialOrder, HashMap<BeliefNode, Integer> tierMap) {
                this.partialOrder = partialOrder;
                this.tierMap = tierMap;
        }

        public java.util.Iterator<Integer> iterator() {
                return new Iterator(this);
        }

        public static class Iterator implements java.util.Iterator<Integer> {

                int idxCurrentLevel;
                Vector<Integer> currentLevel;
                Random random;
                TopologicalOrdering ordering;
                
                public Iterator(TopologicalOrdering ordering) {
                        this.ordering = ordering;
                        idxCurrentLevel = 0;
                        currentLevel = new Vector<Integer>(ordering.partialOrder.get(0));
                        random = new Random();
                }
                
                public boolean hasNext() {
                        return currentLevel != null && !currentLevel.isEmpty();
                }
        
                public Integer next() {
                        if(!hasNext())
                                throw new NoSuchElementException();
                        int idxNext = random.nextInt(currentLevel.size());
                        int nextElem = currentLevel.remove(idxNext);
                        if(currentLevel.isEmpty()) {
                                ++idxCurrentLevel;
                                if(idxCurrentLevel < ordering.partialOrder.size())
                                        currentLevel = new Vector<Integer>(ordering.partialOrder.get(idxCurrentLevel));
                                else
                                        currentLevel = null;
                        }
                        return nextElem;
                }
                
                public void remove() {
                        throw new RuntimeException("remove() is not supported by this constant iterator.");
                }

        }

        public int getTier(BeliefNode n) {
                if(tierMap == null)
                        throw new RuntimeException("Topological ordering has no tier map!");
                return tierMap.get(n);
        }

        public int getNumTiers() {
                return partialOrder.size();
        }
        
        public Vector<Integer> getTier(int index) {
                return partialOrder.get(index);
        }
        
        public Vector<Vector<Integer>> getTiers() {
                return partialOrder;
        }
}

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srldb
Author(s): Dominik Jain, Stefan Waldherr, Moritz Tenorth
autogenerated on Fri Jan 11 09:58:30 2013