Lecture 2 Summary - nus-cs2030/2122-s1 GitHub Wiki

Inheritance

• is-a relationship
• The use of super(...) to access the parent's constructor
• super.method() or super.attribute to access the parent's method and attribute accordingly
• Example Code

class Parent {
    Parent(...) { ... }
    void foo(...) { ... }
    // some other methods
}

class Child extends Parent {
    Child(...) {
        super(...) // Must be the first statement of the constructor if needed
        // somethingelse()?
    }
}

private vs protected

Think of it as treating something like your private bedroom where only you can get in VS your family room where... your whole family can access!

Overriding (@Override) vs Overloading

• Overriding: explicitly defining a method that is the same as the method inherited from another class
• Overloading: having more than one methods to co-exists as long as the arguments are different in configuration