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    package org.sonar.graph;
021    
022    import java.util.Collection;
023    import java.util.Collections;
024    import java.util.Set;
025    
026    public class Dsm<V> {
027    
028      private V[] vertices;
029      private DsmCell[][] cells;
030      private int dimension;
031      private DirectedGraphAccessor<V, ? extends Edge<V>> graph;
032    
033      public Dsm(DirectedGraphAccessor<V, ? extends Edge<V>> graph, Collection<V> vertices, Set<Edge> feedbackEdges) {
034        this.graph = graph;
035        this.dimension = vertices.size();
036        this.cells = new DsmCell[dimension][dimension];
037        initVertices(vertices);
038        initCells(feedbackEdges);
039      }
040    
041      public Dsm(DirectedGraphAccessor<V, ? extends Edge<V>> acyclicGraph, Set<Edge> feedbackEdges) {
042        this(acyclicGraph, acyclicGraph.getVertices(), feedbackEdges);
043      }
044    
045      public Dsm(DirectedGraphAccessor<V, ? extends Edge<V>> acyclicGraph) {
046        this(acyclicGraph, acyclicGraph.getVertices(), Collections.<Edge>emptySet());
047      }
048    
049      private void initCells(Set<Edge> feedbackEdges) {
050        for (int x = 0; x < dimension; x++) {
051          for (int y = 0; y < dimension; y++) {
052            V from = vertices[x];
053            V to = vertices[y];
054    
055            Edge<V> edge = graph.getEdge(from, to);
056            boolean isFeedbackEdge = (edge != null && feedbackEdges.contains(edge));
057            DsmCell cell = new DsmCell(edge, isFeedbackEdge);
058            cells[x][y] = cell;
059          }
060        }
061      }
062    
063      private void initVertices(Collection<V> verticesCol) {
064        this.vertices = (V[]) new Object[dimension];
065        int i = 0;
066        for (V vertex : verticesCol) {
067          vertices[i] = vertex;
068          i++;
069        }
070      }
071    
072      public V getVertex(int rowIndex) {
073        return vertices[rowIndex];
074      }
075    
076      public int getDimension() {
077        return dimension;
078      }
079    
080      public void permute(int fromIndex, int toIndex) {
081        if (fromIndex != toIndex) {
082          checkIndicesBoudaries(fromIndex, toIndex);
083          permuteVertice(fromIndex, toIndex);
084          permuteColumns(fromIndex, toIndex);
085          permuteRows(fromIndex, toIndex);
086        }
087      }
088    
089      private void checkIndicesBoudaries(int... indices) {
090        for (int index : indices) {
091          if (index < 0 || index >= dimension) {
092            StringBuilder builder = new StringBuilder("DSM contains the following vertices : ");
093            for (V vertex : vertices) {
094              builder.append(vertex.toString()).append(" | ");
095            }
096            builder.append(". Trying to reach index ").append(index);
097            throw new ArrayIndexOutOfBoundsException(builder.toString());
098          }
099        }
100      }
101    
102      private void permuteVertice(int fromIndex, int toIndex) {
103        V fromVertex = vertices[fromIndex];
104        V toVertex = vertices[toIndex];
105        vertices[fromIndex] = toVertex;
106        vertices[toIndex] = fromVertex;
107      }
108    
109      private void permuteRows(int fromYIndex, int toYIndex) {
110        for (int x = 0; x < dimension; x++) {
111          permuteCells(x, fromYIndex, x, toYIndex);
112        }
113      }
114    
115      private void permuteColumns(int fromXIndex, int toXIndex) {
116        for (int y = 0; y < dimension; y++) {
117          permuteCells(fromXIndex, y, toXIndex, y);
118        }
119      }
120    
121      private void permuteCells(int fromXIndex, int fromYIndex, int toXIndex, int toYIndex) {
122        DsmCell fromCell = cells[fromXIndex][fromYIndex];
123        DsmCell toCell = cells[toXIndex][toYIndex];
124        cells[toXIndex][toYIndex] = fromCell;
125        cells[fromXIndex][fromYIndex] = toCell;
126      }
127    
128      public int getNumberOfIncomingEdges(int y, int from, int to) {
129        int incomingEdges = 0;
130        for (int x = from; x <= to; x++) {
131          DsmCell cell = cells[x][y];
132          if (cell.getWeight() != 0 && !cell.isFeedbackEdge()) {
133            incomingEdges++;
134          }
135        }
136        return incomingEdges;
137      }
138    
139      public int getNumberOfOutgoingEdges(int x, int from, int to) {
140        int outgoingEdges = 0;
141        for (int y = from; y <= to; y++) {
142          DsmCell cell = cells[x][y];
143          if (cell.getWeight() != 0 && !cell.isFeedbackEdge()) {
144            outgoingEdges++;
145          }
146        }
147        return outgoingEdges;
148      }
149    
150      public DsmCell getCell(int x, int y) {
151        return cells[x][y];
152      }
153    
154      public V[] getVertices() {
155        V[] verticesCopy = (V[]) new Object[vertices.length];
156        System.arraycopy(vertices, 0, verticesCopy, 0, vertices.length);
157        return verticesCopy;
158      }
159    }