19. non-Graphical objects; data structures
- The idea of an object was in-fact first thought of for data structures
- What is a data structure
- More complicated data structures, such as Vectors and Hashtables
19.2.1 The idea of an object was in-fact first thought of for data structures
Thus far, we have been concerned with the exclusive use of graphical components, mainly to learn object oriented programming from a slightly more visual perspective. However, we will not get far in our development of programs, if we only use what we have learned so far. In fact, Object Oriented Programming was not invented for uncomplicated handling of graphical components, but rather uncomplicated handling of data objects. Data Objects are not visually interesting. In fact, they consist solely of data that is not visually represented like a button. We have already developed a user interface for inputing user information, which we simply stored in a TextArea. Useful programs do not just dump data into TextAreas; instead, they organize data in what is called a Data Structure.
19.2.2 What is a data structure
Data structures are also objects in OOP. Just like the objects we have dealt with so far, they have methods that help us in handling the object. Whereas we used getLabel() in order to retrieve the text on a button, we can use similar methods, e.g. getLastName() from a data object. The concept behind Data objects and Graphical Objects is the very same.
19.2.3 More complicated data structures, such as Vectors and Hashtables
[Discussion of a keys and elements in predefined data structures Vector and Hashtable]