/**
* Tries to find a usage of the variable and returns the maximum depth of the relevant
* element inside of the structure.
* @param command the Command to start traversal with
* @return an int >= 0 or null if not found at all
*/
public int checkDepth(ICommandWithWhere command)
{
if (command is IConstruct)
{
// Check head of Construct
foreach (ITripleTemplate template in ((IConstruct)command).getTemplates())
{
if (containsVar(template))
{
result = 0;
}
}
}
else if (command is IModify)
{
IResource modify = command;
if (templateContainsVar(modify.getObject(SP.PropertyInsertPattern)))
{
result = 0;
}
if (templateContainsVar(modify.getObject(SP.PropertyDeletePattern)))
{
result = 0;
}
}
IElementList where = command.getWhere();
if (where != null)
{
walker = new ElementWalkerWithDepth(el, ex);
walker.visit(where);
}
return(result);
}
/**
* Checks whether a given query mentions the variable ?this anywhere.
* This can be used to check whether ?this needs to be bound before
* execution, etc.
* @param command the query to test
* @return null to indicate it was not found, an int >= 0 representing
* the max depth inside query element tree otherwise
*/
public static int containsThis(ICommandWithWhere command)
{
return(new ContainsVarChecker(SPIN.Property_this).checkDepth(command));
}