private GraphPath(GraphPath parent, Identity node, EdgeInfo fromEdge)
{
DomainModel = parent.DomainModel;
_parent = parent;
EndElement = node;
LastTraversedRelationship = fromEdge;
}
///-------------------------------------------------------------------------------------------------
/// <summary>
/// Returns what to do with this path in a traversal query.
/// </summary>
/// <param name="path">
/// Full pathname of the file.
/// </param>
/// <returns>
/// A GraphTraversalEvaluatorResult.
/// </returns>
///-------------------------------------------------------------------------------------------------
public GraphTraversalEvaluatorResult Visit(GraphPath path)
{
return(GraphTraversalEvaluatorResult.IncludeAndContinue);
}
///-------------------------------------------------------------------------------------------------
/// <summary>
/// Called when a path is visited.
/// </summary>
/// <param name="path">
/// Full pathname of the file.
/// </param>
///-------------------------------------------------------------------------------------------------
public void MarkVisited(GraphPath path)
{
DebugContract.Requires(path);
_visited.Add(path);
}
///-------------------------------------------------------------------------------------------------
/// <summary>
/// Returns if a path has been visited.
/// </summary>
/// <param name="path">
/// Full pathname of the file.
/// </param>
/// <returns>
/// True is the path has been visited.
/// </returns>
///-------------------------------------------------------------------------------------------------
public bool IsVisited(GraphPath path)
{
DebugContract.Requires(path);
return(_visited.Contains(path));
}
///-------------------------------------------------------------------------------------------------
/// <summary>
/// Enumerates the items in this collection that meet given criteria.
/// </summary>
/// <param name="node">
/// The node.
/// </param>
/// <returns>
/// An enumerator that allows foreach to be used to process the matched items.
/// </returns>
///-------------------------------------------------------------------------------------------------
public virtual IEnumerable <GraphPath> Traverse(NodeInfo node)
{
DebugContract.Requires(node);
// Création du container de stockage des noeuds (ou plutot des chemins jusqu'à ce noeud) restant à traverser
// Le type est tributaire de l'algorithme de traversé (Queue pour BreadthFirst et Stack pour DepthFirst)
// Ce container est mis à jour à chaque noeud.
var paths = CreatePathContainer();
// Lecture du noeud de départ
if (node == null)
{
yield break;
}
// Constitution du Path courant
var path = new GraphPath(_query.DomainModel, node.Id);
// Initialisation du container avec le 1er noeud
paths.Insert(new[] { path });
// Tant qu'il y a des noeuds à parcourir
while (!paths.IsEmpty)
{
// On prend le prochain noeud à parcourir (dépend de l'algo de traversé)
path = paths.Retrieve();
// On indique que ce noeud a été visité
_query.UnicityPolicy.MarkVisited(path);
// Filtrage du chemin courant pour savoir si on continue
var result = _query.Evaluator.Visit(path);
// Le chemin courant est à prendre en compte
if ((GraphTraversalEvaluatorResult.Include & result) == GraphTraversalEvaluatorResult.Include)
{
// _trace.WriteTrace(TraceCategory.Traverser, "Include : {0}", path);
yield return(path);
}
// Arrêt forcé
if ((result & GraphTraversalEvaluatorResult.Exit) == GraphTraversalEvaluatorResult.Exit)
{
break;
}
if ((result & GraphTraversalEvaluatorResult.Continue) == GraphTraversalEvaluatorResult.Continue)
{
var childPaths = new List <GraphPath>(31);
// Parcours de toutes les relations du noeud courant pour tester si
// on les prend en compte
foreach (var rel in _query.IncidencesIterator.From(path.EndElement))
{
// _trace.WriteTrace(TraceCategory.Traverser, "Visit : {1} for {0}", path, rel.Id);
if (String.Compare(rel.EndId.DomainModelName, _query.DomainModel.Name, StringComparison.OrdinalIgnoreCase) == 0)
{
var childNode = rel.EndId;
var p = path.Create(childNode, rel);
// Si ce chemin n'a pas dèjà été traité, on l'ajoute dans la liste des chemins à traiter
if (!_query.UnicityPolicy.IsVisited(p))
{
// _trace.WriteTrace(TraceCategory.Traverser, "Push : {0}", p);
childPaths.Add(p);
}
}
}
paths.Insert(childPaths);
}
}
}
