source: trunk/sources/HeuristicLab.Core/3.3/Collections/DirectedGraph/DirectedGraph.cs @ 11444

Last change on this file since 11444 was 11444, checked in by bburlacu, 8 years ago

#2223: Added check to prevent adding an arc when the source and the target are the same vertex.

File size: 7.1 KB
Line 
1#region License Information
2/* HeuristicLab
3 * Copyright (C) 2002-2014 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
4 *
5 * This file is part of HeuristicLab.
6 *
7 * HeuristicLab is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 3 of the License, or
10 * (at your option) any later version.
11 *
12 * HeuristicLab is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
19 */
20#endregion
21
22using System;
23using System.Collections.Generic;
24using System.Drawing;
25using System.Linq;
26using HeuristicLab.Common;
27using HeuristicLab.Common.Resources;
28using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
29
30namespace HeuristicLab.Core {
31  [Item("DirectedGraph", "Generic class representing a directed graph with custom vertices and content")]
32  [StorableClass]
33  public class DirectedGraph : Item, IDirectedGraph {
34    public override Image ItemImage { get { return VSImageLibrary.Graph; } }
35
36    private HashSet<IVertex> vertices;
37    [Storable]
38    public IEnumerable<IVertex> Vertices {
39      get { return vertices; }
40      private set { vertices = new HashSet<IVertex>(value); }
41    }
42
43    private HashSet<IArc> arcs;
44    [Storable]
45    public IEnumerable<IArc> Arcs {
46      get { return arcs; }
47      private set { arcs = new HashSet<IArc>(value); }
48    }
49
50    public DirectedGraph() {
51      vertices = new HashSet<IVertex>();
52      arcs = new HashSet<IArc>();
53    }
54
55    protected DirectedGraph(DirectedGraph original, Cloner cloner)
56      : base(original, cloner) {
57      vertices = new HashSet<IVertex>(original.vertices.Select(cloner.Clone));
58      arcs = new HashSet<IArc>(original.arcs.Select(cloner.Clone));
59
60      // add the arcs to the newly cloned vertices
61      foreach (var arc in arcs) {
62        arc.Source.AddArc(arc);
63        arc.Target.AddArc(arc);
64      }
65    }
66
67    public override IDeepCloneable Clone(Cloner cloner) {
68      return new DirectedGraph(this, cloner);
69    }
70
71    [StorableConstructor]
72    protected DirectedGraph(bool serializing)
73      : base(serializing) {
74    }
75
76    [StorableHook(HookType.AfterDeserialization)]
77    private void AfterDeserialization() {
78      foreach (var vertex in vertices) {
79        vertex.ArcAdded += Vertex_ArcAdded;
80        vertex.ArcRemoved += Vertex_ArcRemoved;
81      }
82
83      foreach (var arc in arcs) {
84        var source = arc.Source;
85        var target = arc.Target;
86        source.AddArc(arc);
87        target.AddArc(arc);
88      }
89    }
90
91    public virtual void Clear() {
92      vertices.Clear();
93      arcs.Clear();
94    }
95
96    public virtual void AddVertex(IVertex vertex) {
97      if (!vertices.Contains(vertex) && vertex.Degree > 0)
98        throw new ArgumentException("New vertices cannot have any arcs.");
99
100      if (vertices.Add(vertex)) {
101        // register event handlers
102        vertex.ArcAdded += Vertex_ArcAdded;
103        vertex.ArcRemoved += Vertex_ArcRemoved;
104        OnVertedAdded(this, new EventArgs<IVertex>(vertex));
105      }
106    }
107
108    public virtual void AddVertices(IEnumerable<IVertex> vertexList) {
109      var hash = new HashSet<IVertex>(vertexList);
110      var arcList = vertexList.SelectMany(v => v.InArcs.Concat(v.OutArcs));
111      if (arcList.Any(x => !hash.Contains(x.Source) || !hash.Contains(x.Target)))
112        throw new ArgumentException("Vertex arcs are connected to vertices not in the graph.");
113      // if everything is in order, add the vertices to the directed graph
114      foreach (var v in vertexList)
115        vertices.Add(v);
116      foreach (var a in arcList)
117        arcs.Add(a);
118    }
119
120    public virtual void RemoveVertices(IEnumerable<IVertex> vertexList) {
121      foreach (var v in vertexList)
122        RemoveVertex(v);
123    }
124
125    public virtual void RemoveVertex(IVertex vertex) {
126      vertices.Remove(vertex);
127      // remove connections to/from the removed vertex
128      var arcList = vertex.InArcs.Concat(vertex.OutArcs).ToList(); // avoid invalid operation exception: "collection was modified" below
129      foreach (var arc in arcList)
130        RemoveArc(arc);
131      // deregister event handlers
132      vertex.ArcAdded -= Vertex_ArcAdded;
133      vertex.ArcRemoved -= Vertex_ArcRemoved;
134      OnVertexRemoved(this, new EventArgs<IVertex>(vertex));
135    }
136
137    public virtual IArc AddArc(IVertex source, IVertex target) {
138      var arc = new Arc(source, target);
139      AddArc(arc);
140      return arc;
141    }
142
143    public virtual void AddArc(IArc arc) {
144      var source = arc.Source;
145      var target = arc.Target;
146
147      if (source == target)
148        throw new InvalidOperationException("Source and target cannot be the same.");
149
150      if (!vertices.Contains(source) || !vertices.Contains(target))
151        throw new InvalidOperationException("Cannot add arc connecting vertices that are not in the graph.");
152
153      source.AddArc(arc);
154      target.AddArc(arc);
155      arcs.Add(arc);
156    }
157
158    public virtual void RemoveArc(IArc arc) {
159      arcs.Remove(arc);
160      var source = (Vertex)arc.Source;
161      var target = (Vertex)arc.Target;
162      source.RemoveArc(arc);
163      target.RemoveArc(arc);
164    }
165
166    protected virtual void Vertex_ArcAdded(object sender, EventArgs<IArc> args) {
167      // the ArcAdded event is fired by a vertex when an arc from/to another vertex is added to its list of connections
168      // because the arc is added in both directions by both the source and the target, this event will get fired twice here
169      var arc = args.Value;
170      if (arcs.Add(arc)) OnArcAdded(this, new EventArgs<IArc>(arc));
171    }
172
173    protected virtual void Vertex_ArcRemoved(object sender, EventArgs<IArc> args) {
174      var arc = args.Value;
175      if (arcs.Remove(arc)) OnArcRemoved(this, new EventArgs<IArc>(arc));
176    }
177
178    // events
179    public event EventHandler<EventArgs<IVertex>> VertexAdded;
180    protected virtual void OnVertedAdded(object sender, EventArgs<IVertex> args) {
181      var added = VertexAdded;
182      if (added != null)
183        added(sender, args);
184    }
185
186    public event EventHandler<EventArgs<IVertex>> VertexRemoved;
187    protected virtual void OnVertexRemoved(object sender, EventArgs<IVertex> args) {
188      var removed = VertexRemoved;
189      if (removed != null)
190        removed(sender, args);
191    }
192
193    public event EventHandler<EventArgs<IArc>> ArcAdded;
194    protected virtual void OnArcAdded(object sender, EventArgs<IArc> args) {
195      var added = ArcAdded;
196      if (added != null)
197        added(sender, args);
198    }
199
200    public event EventHandler<EventArgs<IArc>> ArcRemoved;
201    protected virtual void OnArcRemoved(object sender, EventArgs<IArc> args) {
202      var removed = ArcRemoved;
203      if (removed != null)
204        removed(sender, args);
205    }
206  }
207}
Note: See TracBrowser for help on using the repository browser.