/**
* visit.
*
* @param obj a {@link lupos.rif.model.Conjunction} object.
* @param arg a {@link lupos.rif.IRuleNode} object.
* @return a {@link lupos.rif.IRuleNode} object.
* @throws lupos.rif.RIFException if any.
*/
public IRuleNode visit(Conjunction obj, IRuleNode arg) throws RIFException {
obj.setParent(arg);
List<IExpression> items = new ArrayList<IExpression>(obj.exprs);
obj.exprs.clear();
for (IExpression expr : items) obj.addExpr((IExpression) expr.accept(this, obj));
return obj;
}
/**
* visit.
*
* @param obj a {@link lupos.rif.model.RulePredicate} object.
* @param arg a {@link lupos.rif.IRuleNode} object.
* @return a {@link lupos.rif.IRuleNode} object.
* @throws lupos.rif.RIFException if any.
*/
public IRuleNode visit(RulePredicate obj, IRuleNode arg) throws RIFException {
obj.setParent(arg);
Conjunction conjunction = null;
List<IExpression> items = new ArrayList<IExpression>(obj.termParams);
obj.termParams.clear();
for (IExpression expr : items) {
final IRuleNode result = expr.accept(this, obj);
if (result instanceof Conjunction) {
conjunction = conjunction == null ? new Conjunction() : conjunction;
for (IExpression item : ((Conjunction) result).exprs)
if (item instanceof RulePredicate) conjunction.addExpr(item);
else if (item instanceof RuleVariable) obj.termParams.add(item);
} else obj.termParams.add((IExpression) result);
}
if (conjunction != null) conjunction.addExpr(obj);
return conjunction == null ? obj : conjunction;
}
/**
* visit.
*
* @param obj a {@link lupos.rif.model.RuleList} object.
* @param arg a {@link lupos.rif.IRuleNode} object.
* @return a {@link lupos.rif.IRuleNode} object.
* @throws lupos.rif.RIFException if any.
*/
public IRuleNode visit(RuleList obj, IRuleNode arg) throws RIFException {
try {
// Wenn Liste leer
if (obj.getItems().isEmpty()) {
return new Constant(
LiteralFactory.createURILiteral("<http://www.w3.org/1999/02/22-rdf-syntax-ns#nil>"),
arg);
}
Conjunction conjunction = new Conjunction();
conjunction.setParent(arg);
int iteration = 0;
// Listenidentifikator erstellen
String baseName = aliasString + "list" + listCtr++ + "it";
conjunction.addExpr(new RuleVariable(baseName + iteration));
int ctr = obj.getItems().size();
for (IExpression expr : obj.getItems()) {
ctr--;
IRuleNode result = expr.accept(this, conjunction);
final String itVar = baseName + iteration++;
if (result instanceof Conjunction) {
for (IExpression item : new ArrayList<IExpression>(((Conjunction) result).exprs))
if (item instanceof RulePredicate) conjunction.addExpr(item);
else if (item instanceof RuleVariable) result = item;
}
final RulePredicate item =
new RulePredicate(
new RuleVariable(itVar),
new Constant(
LiteralFactory.createURILiteral(
"<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>"),
arg),
(IExpression) result);
conjunction.addExpr(item);
final RulePredicate next =
new RulePredicate(
new RuleVariable(itVar),
new Constant(
LiteralFactory.createURILiteral(
"<http://www.w3.org/1999/02/22-rdf-syntax-ns#rest>"),
arg),
ctr == 0
? new Constant(
LiteralFactory.createURILiteral(
"<http://www.w3.org/1999/02/22-rdf-syntax-ns#nil>"),
arg)
: new RuleVariable(baseName + iteration));
conjunction.addExpr(next);
currentVariableScope.addVariable(new RuleVariable(itVar));
}
return conjunction;
} catch (URISyntaxException e) {
throw new RIFException(e.getMessage());
}
}