Zusammenfassung der Ressource
Java
- Constructor
Anmerkungen:
- Aufgabe: Create an instance of a class
- Return Types
- None! Note even "Void"
- Methods
Anmerkungen:
- Aufgabe: execute Java Code
- Return Types
- Any and none (void)
- Object
Anmerkungen:
- The term ‘object’, however, refers to an actual instance
of a class. Every object must belong to a class. Objects are created
and eventually destroyed – so they only live in the program for a
limited time. While objects are ‘living’ their properties may also be
changed signficantly.
An example will help clarify what we’ve said. Suppose
we have a class called ‘Animal’. All Animals have bodies and brains.
So, this general ‘template’ of an Animal does not change.
An instance of the Animal class would be a specific
animal – like a lion, a cat, or a zebra. These instances of the
Animal class would be called objects. Whereas the Animal class is a
general concept, the instances of that class – the lions, cats, etc –
take that general concept and create a real instance of it.
- Class
Anmerkungen:
- The term ‘class’ refers to the actual written piece of code in which the
class is defined. A class is a static piece of code that consists of
attributes which don’t change during the execution of a program – like
the method definitions within a class.
- API (Application programming interface)
Anmerkungen:
- An application programming interface (API) specifies how some software components should interact with each other.
Anlagen:
- Implementation
Anmerkungen:
- Objekte werden implementiert
- instance Variables
- private String name
- In this case you are neither adding the name to a list, nor are you assigning a particular value to the string.
All you are doing is declaring the name of the String object variable.
- Local Variables
- "Verschwinden, wenn Methode abgeschlossen" (Kurzzeitgedächtnis)