/**
* Advanced checking of an expression, needed because Expression.fromString() might terminate
* normally, but returned Expression will not be appliable for real Entities. Current
* implementation assures all attributes in expression are present in Entity
*
* @param root Root of a query
* @param ex Expression to check
* @throws ValidationException when something's wrong
*/
static void checkExpression(Entity root, Expression ex) throws ValidationException {
try {
if (ex instanceof ASTPath) {
/**
* Try to iterate through path, if some attributes are not present, exception will be raised
*/
Iterator<CayenneMapEntry> path = root.resolvePathComponents(ex);
while (path.hasNext()) {
path.next();
}
}
if (ex != null) {
for (int i = 0; i < ex.getOperandCount(); i++) {
if (ex.getOperand(i) instanceof Expression) {
checkExpression(root, (Expression) ex.getOperand(i));
}
}
}
} catch (ExpressionException eex) {
throw new ValidationException(eex.getUnlabeledMessage());
}
}