Java Classes and Objects

A class is a blueprint; an object is one thing built from it. Classes bundle fields (data) and methods (behaviour).

ExampleJava

public class Main {
  static class Dog {
    String name;
    int age;

    void bark() {
      System.out.println(name + " says woof");
    }
  }

  public static void main(String[] args) {
    Dog rex = new Dog();
    rex.name = "Rex";
    rex.age = 3;
    rex.bark();

    Dog fido = new Dog();
    fido.name = "Fido";
    fido.bark();
  }
}

Output

Rex says woof
Fido says woof

Quick check

Which keyword creates an object?

makenewcreate

Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.

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