public boolean isVariableArrity() {
int numFormals;
if ((numFormals = formalTypes().size()) > 0) {
Type last = (Type) formalTypes().get(numFormals - 1);
if (last instanceof JL5ArrayType) {
JL5ArrayType lastAsArr = (JL5ArrayType) last;
if (lastAsArr.isVarargs()) return true;
}
}
return false;
}
public boolean callValid(Type thisType, List<Type> argTypes, Context context) {
JL5TypeSystem ts = (JL5TypeSystem) typeSystem();
List<Type> l1 = this.formalTypes();
List<Type> l2 = argTypes;
if ((l1.size() == 0) && (l2.size() != 0)) return false;
Iterator<Type> itCallee = l1.iterator();
Iterator<Type> itCaller = l2.iterator();
// caller can either:
// - have one argument less than callee (last argument of
// callee is a varargs and caller do not provide a value)
// - have same number of args. The last arg being either
// - same type as the last arg of callee
// - or same type as the last arg of callee which is a varargs array
// - or an array of same type as the last arg of callee (which could be a varargs array)
// - have more args, then:
// - last args of callee must be a varargs array
// - all extra args provided by the caller must match
// the varargs array type of the callee.
while (itCallee.hasNext() && itCaller.hasNext()) {
Type t1 = itCallee.next();
Type t2 = itCaller.next();
// Varargs can be used only in the final argument position
// When we reach the final argument, we check if it is varargs array.
if (!itCallee.hasNext() && t1.isArray() && ((JL5ArrayType) t1).isVarargs()) {
JL5ArrayType vartype = (JL5ArrayType) t1;
// Every arguments remaining in the second iterator must match the type
// of the varargs array
if (!itCaller.hasNext()) {
// if we also reached the last element of the caller,
// check if the type matches or if it is an array
return ts.isImplicitCastValid(t2, vartype, context)
|| ts.isImplicitCastValid(t2, vartype.base(), context);
} else {
// There are several arguments left, they should all match the callee's varargs array
// type.
while (itCaller.hasNext()) { // eat up actual args
if (!ts.isImplicitCastValid(t2, vartype.base(), context)) {
return false;
}
t2 = itCaller.next();
}
}
} else {
if (!ts.isImplicitCastValid(t2, t1, context)) {
return false;
}
}
}
// Caller provided less args than the callee has, which is legal
// if callee is a variable arity method
if (itCallee.hasNext() && isVariableArrity()) {
itCallee.next();
}
// and we've reached callee's last arg.
return !(itCallee.hasNext() || itCaller.hasNext());
}