SAP Webdynpro JAVA Interview questions

1. Webdynpro framework is based on which design pattern?
MVC design pattern.
2. What is a component?
A component is the unit of project which contains the actual functionality and it can be reused
3. What is a model?
A model is any layer of code that encapsulates some business functionality external to the
Web Dyn-pro environment.
4. What is the difference between component controller and view controller?
Component controller is the main controller of the entire component and it’s a global controller. View controller is the controller associated with a view.
5. Which all are the global controllers
Component controller and custom controller
6. What does the component interface contains?
The Web Dynpro component interface consists of two parts: a visual one and a programmatic one, and defines the set of publicly accessible entry points to the component. Visual part is interface view which corresponds to a window in component and the programmatic part is Interface controller.
7. What is a context?
All controllers, whether view controllers, custom controllers or component controllers, have a dynamic data storage area known as a context. Context contains nodes and attributes where data is stored
8. What is cardinality of a node?
Cardinality represents the number of elements a node has at the start of the application and maximum number of elements it could have during its life time
9. What is a singleton node?
Singleton nodes are represented by a single node instance, whose content – that is, its node collection - changes each time the lead selection of the parent node changes.
10. What is the purpose of supply function in a node?
Supply Function is used to populate the values in a node on demand. The supply function is called by the runtime when the data of the context node is used. This is the case when a UI element is to be displayed for the first time with the data of the corresponding context