I have come across tools like visualparadigm demo which could automatically generate code from the class diagram which is modelled in UML. Since I have no industry experience, I am curious to know whether this is the way companies start working on their projects after the system is modelled in UML. since the skeleton of the classes needed is automatically generated, I assume it is a good way to save time. If this is not the way, then why is it so?
Also Can you provide me some other tools which can automatically generate code from UML class diagrams (prefer opensource).
Are there OOP software projects which do not get started with the class diagrams, so that this method can be of no use?
Most of UML are able to generate code from UML class diagram you just have to google it and you will find them.
Concerning the way companies start working, I guess it depends of the companies but from my experience companies try to avoid useless work. If they spend some time on modeling it is because they can use it for something for example code generation, documentation, or just because its a client request. If companies do not find any interest in modelling they simply do not use it I guess that alot of OOP do not start with models.