OOP Basics

1public class Developer {
2    // Fields (properties)
3    private String name;
4    private String language;
5    private int experience;
6 
7    // Constructor
8    public Developer(String name, String language, int experience) {
9        this.name = name;
10        this.language = language;
11        this.experience = experience;
12    }
13 
14    // Method
15    public String introduce() {
16        return name + " | " + language + " dev | " + experience + " yrs";
17    }
18 
19    public static void main(String[] args) {
20        Developer dev = new Developer("Alice", "Java", 3);
21        System.out.println(dev.introduce());
22    }
23}

1class Animal {
2    protected String name;
3 
4    public Animal(String name) {
5        this.name = name;
6    }
7 
8    public String speak() {
9        return name + " makes a sound.";
10    }
11}
12 
13class Dog extends Animal {
14    public Dog(String name) {
15        super(name);
16    }
17 
18    @Override
19    public String speak() {
20        return name + " barks!";
21    }
22}
23 
24// Usage:
25// Animal a = new Dog("Rex");
26// System.out.println(a.speak()); // Rex barks!