Simple code lesson created for newbies

Dog.java

public class Dog {

	private String name;

	private int age;
	
	public final static String FAMILY = "Canine";
	
	// constructors create objects (instances of classes)
	public Dog(String name, int age) {
		this.name = name;
		this.age = age;
	}
	
	// 'void' methods don't return a value
	public void bark() {
		// "woof" is a String ~literal~
		System.out.println("woof");
	}
	
	// this method returns a String literal
	public String speak() {
		// '+' is the String concatenation operator
		return "My name is " + name;
	}
	
	public int equivalentHumanAge() {
		// 7 is what we call a 'magic number'. that's bad.
		// we'd usually create a constant
		return 7*age;
	}
}

DogTest.java

public class DogTest {

	public static void main(String[] args) {
		Dog shortDog = new Dog("Short Dog", 14);
		shortDog.bark();
		
		//when we tell him to speak, he responds
		String response = shortDog.speak();
		System.out.println("Short Dog says [" + response + "].");
		
		int humanAge = shortDog.equivalentHumanAge();
		System.out.println("If I were a human, I'd be " + humanAge);
	}

}