In ADO.NET, IDbCommand.CreateParameter is an example of the use of factory method to connect parallel class hierarchies. In Qt, QMainWindow::createPopupMenu is a factory method declared in a framework that can be overridden in application code. In Java, several factories are used in the javax.xml.parsers package. e.g. javax.xml.parsers.DocumentBuilderFactory or javax.xml.parsers.SAXParserFactory.