001/*
002 * Sonar, open source software quality management tool.
003 * Copyright (C) 2008-2012 SonarSource
004 * mailto:contact AT sonarsource DOT com
005 *
006 * Sonar is free software; you can redistribute it and/or
007 * modify it under the terms of the GNU Lesser General Public
008 * License as published by the Free Software Foundation; either
009 * version 3 of the License, or (at your option) any later version.
010 *
011 * Sonar is distributed in the hope that it will be useful,
012 * but WITHOUT ANY WARRANTY; without even the implied warranty of
013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014 * Lesser General Public License for more details.
015 *
016 * You should have received a copy of the GNU Lesser General Public
017 * License along with Sonar; if not, write to the Free Software
018 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
019 */
020
021package org.sonar.graph;
022
023import java.util.ArrayList;
024import java.util.Collections;
025import java.util.Iterator;
026import java.util.List;
027import java.util.Set;
028
029import com.google.common.collect.HashMultiset;
030import com.google.common.collect.Multiset;
031
032/**
033 * Note: this class has a natural ordering that is inconsistent with equals
034 */
035public final class FeedbackCycle implements Iterable<FeedbackEdge>, Comparable<FeedbackCycle> {
036
037  private List<FeedbackEdge> orderedFeedbackEdges;
038  private int totalOccurrencesOfEdgesInCycle;
039  private final Cycle cycle;
040
041  private FeedbackCycle(Cycle cycle) {
042    orderedFeedbackEdges = new ArrayList<FeedbackEdge>();
043    totalOccurrencesOfEdgesInCycle = 0;
044    this.cycle = cycle;
045  }
046
047  private void add(FeedbackEdge feedbackEdge) {
048    orderedFeedbackEdges.add(feedbackEdge);
049  }
050
051  public static List<FeedbackCycle> buildFeedbackCycles(Set<Cycle> cycles) {
052    Multiset<Edge> edgesBag = createBagWithAllEdgesOfCycles(cycles);
053
054    List<FeedbackCycle> feedbackCycles = new ArrayList<FeedbackCycle>();
055    for (Cycle cycle : cycles) {
056      FeedbackCycle feedbackCycle = new FeedbackCycle(cycle);
057      int totalOccurrences = 0;
058      for (Edge edge : cycle.getEdges()) {
059        FeedbackEdge feedbackEdge = new FeedbackEdge(edge, edgesBag.count(edge));
060        feedbackCycle.add(feedbackEdge);
061        totalOccurrences += feedbackEdge.getOccurences();
062      }
063      feedbackCycle.setTotalOccurrencesOfEdgesInCycle(totalOccurrences);
064      Collections.sort(feedbackCycle.orderedFeedbackEdges);
065      feedbackCycles.add(feedbackCycle);
066    }
067    Collections.sort(feedbackCycles);
068
069    return feedbackCycles;
070  }
071
072  private static Multiset<Edge> createBagWithAllEdgesOfCycles(Set<Cycle> cycles) {
073    Multiset<Edge> edgesBag = HashMultiset.create();
074    for (Cycle cycle : cycles) {
075      for (Edge edge : cycle.getEdges()) {
076        edgesBag.add(edge);
077      }
078    }
079    return edgesBag;
080  }
081
082  private void setTotalOccurrencesOfEdgesInCycle(int totalOccurrencesOfEdgesInCycle) {
083    this.totalOccurrencesOfEdgesInCycle = totalOccurrencesOfEdgesInCycle;
084  }
085
086  public int getTotalOccurrencesOfEdgesInCycle() {
087    return totalOccurrencesOfEdgesInCycle;
088  }
089
090  public Iterator<FeedbackEdge> iterator() {
091    return orderedFeedbackEdges.iterator();
092  }
093
094  public int compareTo(FeedbackCycle feedbackCycle) {
095    if (getTotalOccurrencesOfEdgesInCycle() < feedbackCycle.getTotalOccurrencesOfEdgesInCycle()) {//NOSONAR this class has a natural ordering that is inconsistent with equals
096      return -1;
097    }
098    if (getTotalOccurrencesOfEdgesInCycle() == feedbackCycle.getTotalOccurrencesOfEdgesInCycle()) {
099      if (cycle.size() == feedbackCycle.cycle.size()) {
100        return orderedFeedbackEdges.get(0).compareTo(feedbackCycle.orderedFeedbackEdges.get(0));
101      }
102      return cycle.size() - feedbackCycle.cycle.size();
103    }
104    return 1;
105  }
106
107  public Cycle getCycle() {
108    return cycle;
109  }
110}