public boolean isBound(RuleVariable var, Collection<RuleVariable> boundVars) {
if (leftExpr.equals(var) && !boundVars.contains(var)) {
if (rightExpr instanceof RuleVariable) if (!boundVars.contains(rightExpr)) return false;
boundVars.add(var);
return true;
}
if (rightExpr.equals(var) && !boundVars.contains(var)) {
if (leftExpr instanceof RuleVariable) if (!boundVars.contains(leftExpr)) return false;
boundVars.add(var);
return true;
}
// TODO:Testen ob ?var = External() muster vorhanden ist, ?x gebunden
// ist und External die gesuchte Variable enth�lt, die restlichen aber
// gebunden sind, dann gebunden.
if (leftExpr instanceof RuleVariable
&& boundVars.contains(leftExpr)
&& rightExpr instanceof External) {
Set<RuleVariable> extVars = rightExpr.getVariables();
boolean found = false;
boolean bound = true;
for (final RuleVariable ruleVar : extVars)
if (ruleVar.equals(var)) found = true;
else if (!boundVars.contains(ruleVar)) bound = false;
if (found && bound && rightExpr.isBound(var, boundVars)) {
return true;
}
}
if (rightExpr instanceof RuleVariable
&& boundVars.contains(rightExpr)
&& leftExpr instanceof External) {
Set<RuleVariable> extVars = leftExpr.getVariables();
boolean found = false;
boolean bound = true;
for (final RuleVariable ruleVar : extVars)
if (ruleVar.equals(var)) found = true;
else if (!boundVars.contains(ruleVar)) bound = false;
if (found && bound && leftExpr.isBound(var, boundVars)) {
return true;
}
}
return false;
}
public Object evaluate(
Bindings binding, Object result, Multimap<IExpression, IExpression> equalities) {
// Mehrere M�glichkeiten die auftreten k�nnen
boolean leftHasUnbound = false;
boolean rightHasUnbound = false;
boolean leftAssign = false;
boolean rightAssign = false;
Set<Variable> bindingVars = binding.getVariableSet();
for (RuleVariable var : leftExpr.getVariables())
if (!bindingVars.contains(var.getVariable())) {
leftHasUnbound = true;
// Linke ungebunden, muss allein stehen
if (leftExpr instanceof RuleVariable) leftAssign = true;
}
for (RuleVariable var : rightExpr.getVariables())
if (!bindingVars.contains(var.getVariable())) {
rightHasUnbound = true;
// Linke ungebunden, muss allein stehen
if (rightExpr instanceof RuleVariable) rightAssign = true;
}
if (rightAssign && leftAssign)
throw new RIFException("All Variables in Assignment " + toString() + " are unbound!");
if (rightAssign ^ leftAssign) {
// Einzelne ungebundene variable auf einer seite, dann einfach die
// andere auswerten und ergebniss reinschreiben
Literal assignValue =
(Literal) (leftAssign ? rightExpr.evaluate(binding) : leftExpr.evaluate(binding));
RuleVariable var = (RuleVariable) (leftAssign ? leftExpr : rightExpr);
binding.add(var.getVariable(), assignValue);
return BooleanLiteral.TRUE;
} else {
// fester wert auf jeder seite, also erst aussage mit gebundenen
// variable auswerten und anderem als result mitgeben.
Item left = null;
Item right = null;
if (rightHasUnbound) {
left = (Item) leftExpr.evaluate(binding);
right = (Item) rightExpr.evaluate(binding, left);
} else if (leftHasUnbound) {
right = (Item) rightExpr.evaluate(binding);
left = (Item) leftExpr.evaluate(binding, right);
} else {
left = (Item) leftExpr.evaluate(binding);
right = (Item) rightExpr.evaluate(binding);
}
return BooleanLiteral.create(left.equals(right));
}
}
