/// <summary>
/// Gets the value of the expression as evaluated in a given Context for a given Binding.
/// </summary>
/// <param name="context">Evaluation Context.</param>
/// <param name="bindingID">Binding ID.</param>
/// <returns></returns>
public override IValuedNode Evaluate(SparqlEvaluationContext context, int bindingID)
{
_funcContext = context[SparqlSpecsHelper.SparqlKeywordBNode] as BNodeFunctionContext;
if (_funcContext == null)
{
_funcContext = new BNodeFunctionContext(context.InputMultiset.GetHashCode());
context[SparqlSpecsHelper.SparqlKeywordBNode] = _funcContext;
}
else if (_funcContext.CurrentInput != context.InputMultiset.GetHashCode())
{
// Clear the Context
_funcContext.BlankNodes.Clear();
context[SparqlSpecsHelper.SparqlKeywordBNode] = _funcContext;
}
if (_expr == null)
{
// If no argument then always a fresh BNode
return(_funcContext.Graph.CreateBlankNode().AsValuedNode());
}
else
{
INode temp = _expr.Evaluate(context, bindingID);
if (temp != null)
{
if (temp.NodeType == NodeType.Literal)
{
ILiteralNode lit = (ILiteralNode)temp;
if (lit.DataType == null)
{
if (lit.Language.Equals(string.Empty))
{
if (!_funcContext.BlankNodes.ContainsKey(bindingID))
{
_funcContext.BlankNodes.Add(bindingID, new Dictionary <string, INode>());
}
if (!_funcContext.BlankNodes[bindingID].ContainsKey(lit.Value))
{
_funcContext.BlankNodes[bindingID].Add(lit.Value, _funcContext.Graph.CreateBlankNode());
}
return(_funcContext.BlankNodes[bindingID][lit.Value].AsValuedNode());
}
else
{
throw new RdfQueryException("Cannot create a Blank Node when the argument Expression evaluates to a lanuage specified literal");
}
}
else
{
throw new RdfQueryException("Cannot create a Blank Node when the argument Expression evaluates to a typed literal node");
}
}
else
{
throw new RdfQueryException("Cannot create a Blank Node when the argument Expression evaluates to a non-literal node");
}
}
else
{
throw new RdfQueryException("Cannot create a Blank Node when the argument Expression evaluates to null");
}
}
}
/// <summary>
/// Gets the value of the expression as evaluated in a given Context for a given Binding
/// </summary>
/// <param name="context">Evaluation Context</param>
/// <param name="bindingID">Binding ID</param>
/// <returns></returns>
public override IValuedNode Evaluate(SparqlEvaluationContext context, int bindingID)
{
this._funcContext = context[SparqlSpecsHelper.SparqlKeywordBNode] as BNodeFunctionContext;
if (this._funcContext == null)
{
this._funcContext = new BNodeFunctionContext(context.InputMultiset.GetHashCode());
context[SparqlSpecsHelper.SparqlKeywordBNode] = this._funcContext;
}
else if (this._funcContext.CurrentInput != context.InputMultiset.GetHashCode())
{
this._funcContext = new BNodeFunctionContext(context.InputMultiset.GetHashCode());
context[SparqlSpecsHelper.SparqlKeywordBNode] = this._funcContext;
}
if (this._expr == null)
{
//If no argument then always a fresh BNode
return new BlankNode(this._funcContext.Graph, this._funcContext.Mapper.GetNextID());
}
else
{
INode temp = this._expr.Evaluate(context, bindingID);
if (temp != null)
{
if (temp.NodeType == NodeType.Literal)
{
ILiteralNode lit = (ILiteralNode)temp;
if (lit.DataType == null)
{
if (lit.Language.Equals(string.Empty))
{
if (!this._funcContext.BlankNodes.ContainsKey(bindingID))
{
this._funcContext.BlankNodes.Add(bindingID, new Dictionary<string, INode>());
}
if (!this._funcContext.BlankNodes[bindingID].ContainsKey(lit.Value))
{
this._funcContext.BlankNodes[bindingID].Add(lit.Value, new BlankNode(this._funcContext.Graph, this._funcContext.Mapper.GetNextID()));
}
return this._funcContext.BlankNodes[bindingID][lit.Value].AsValuedNode();
}
else
{
throw new RdfQueryException("Cannot create a Blank Node whne the argument Expression evaluates to a lanuage specified literal");
}
}
else
{
throw new RdfQueryException("Cannot create a Blank Node when the argument Expression evaluates to a typed literal node");
}
}
else
{
throw new RdfQueryException("Cannot create a Blank Node when the argument Expression evaluates to a non-literal node");
}
}
else
{
throw new RdfQueryException("Cannot create a Blank Node when the argument Expression evaluates to null");
}
}
}