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Constructors

Caleb Thomas

Caleb Thomas

5 min read

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Study Guide Overview

This study guide covers object-oriented programming in Java, focusing on classes, objects, constructors, and class design. It uses the Student and Assignment classes as examples to illustrate key concepts like instance variables, constructor parameters, and default constructors. The guide also highlights the difference between local and instance variables, discusses mutable objects in constructors, and provides exam tips and strategies.

🚀 AP Computer Science A: Night Before Review 🚀

Welcome! Let's get you feeling confident and ready for your exam. This guide is designed to be your quick, high-impact review. We'll focus on key concepts, common pitfalls, and exam strategies. Let's do this!

📚 Object-Oriented Programming: Constructors & Class Design

Understanding Classes and Objects

  • Classes are blueprints for creating objects. They define the state (data) and behavior (methods) of objects.
  • Objects are instances of a class. Each object has its own unique state.

The Student Class: A Deep Dive

Let's start with the Student class. Here's the initial structure:

java
public class Student {
    private int gradeLevel;
    private String name;
    private int age;
    private Assignment assignment;
}
  • Instance Variables: These are the attributes that define the state of a Student object. They are declared using the private keyword, which means they can only be accessed within the Student class itself.
    • gradeLevel (int): The student's grade level.
    • name (String): The student's full name.
    • age (int): The student's age.
    • assignment (Assignment): An Assignment object associ...