Inheritance

Inheritance

1. extends only one class

   • Parent class
   • child class
   • is-a relationship

2. superclass

   • object class

3. subclass

4. accessibility

   • visibility in the superclass reduced from the subclass
   • the subclass can access the superclass' private and public methods, but not its protected methods

5. instance of keyword

   • tests type of object
   • used in 'if' statement

6. type casting

   • up-casting: casts object to parent class
   • child class can only be casted to its parent class

7. method overriding

   • when ≥ 2 methods in a class have the same method name, but different parameters

8. method overloading

   • having 2 methods with the same name and parameters
   • One method is in the parent class, while the other is in the child class