/**
* Returns the most specific Java instance for a given INode.
* If the node is an aggregation, it will be returned as instance of
* Aggregation.
* If the node is a function call, it will be returned as instance of
* FunctionCall.
* If it's a Variable, the Variable will be returned.
* Otherwise the node itself will be returned.
* @param node the node to cast
* @return node or node as a Function or Variable
*/
public static IResource asExpression(IResource resource)
{
if (resource == null)
{
return(null);
}
if (resource is INode)
{
IVariable var = SPINFactory.asVariable(resource);
if (var != null)
{
return(var);
}
IAggregation aggr = SPINFactory.asAggregation((IResource)resource);
if (aggr != null)
{
return(aggr);
}
IFunctionCall functionCall = SPINFactory.asFunctionCall((IResource)resource);
if (functionCall != null)
{
return(functionCall);
}
}
return(resource);
}
public IVariable getAs()
{
IResource node = this.getObject(SP.PropertyAs);
if (node != null)
{
return(SPINFactory.asVariable(node));
}
else
{
return(null);
}
}
public IVariable getServiceVariable()
{
IResource s = getResource(SP.PropertyServiceURI);
if (s != null)
{
IVariable variable = SPINFactory.asVariable(s);
if (variable != null)
{
return(variable);
}
}
return(null);
}
public Uri getServiceURI()
{
IResource s = getResource(SP.PropertyServiceURI);
if (s != null && s.isUri())
{
IVariable variable = SPINFactory.asVariable(s);
if (variable == null)
{
return(s.Uri);
}
}
return(null);
}
public List <IResource> getResultNodes()
{
List <IResource> results = new List <IResource>();
foreach (IResource node in getList(SP.PropertyResultNodes))
{
IVariable variable = SPINFactory.asVariable(node);
if (variable != null)
{
results.Add(variable);
}
else if (node.isUri())
{
results.Add(node);
}
}
return(results);
}
public IResource getNameNode()
{
IResource r = getObject(SP.PropertyGraphNameNode);
if (r != null)
{
IVariable variable = SPINFactory.asVariable(r);
if (variable != null)
{
return(variable);
}
else
{
return(r);
}
}
else
{
return(null);
}
}
protected IResource getRDFNodeOrVariable(INode predicate)
{
IResource node = getResource(predicate);
if (node != null)
{
IVariable var = SPINFactory.asVariable(node);
if (var != null)
{
return(var);
}
else
{
return(node);
}
}
else
{
return(null);
}
}
public static void printVarOrResource(ISparqlPrinter p, IResource resource)
{
IVariable variable = SPINFactory.asVariable(resource);
if (variable != null)
{
variable.Print(p);
}
else if (resource.isUri())
{
p.printURIResource(resource);
}
else if (p.isNamedBNodeMode())
{
// TODO is this correct ?
p.print(resource.ToString());
}
else
{
p.print("[]");
}
}