Getters and Setters in Java in Java

class Dog {
    private int age;

    public Dog(int age) {
        this.age = age;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int value) {
        if (value >= 0) {
            age = value;
        }
    }
}

Full lesson:

In the Access Modifiers lesson, getName() let other code read a private field. Often other code must change a field too. A setter allows that, and it checks each new value first.

The getter

The getter returns the private field. Other code calls rex.getAge() to read the age.

The setter

The setter gets the new value as a parameter. Other code calls rex.setAge(4) to change the age.

The rule

A dog's age can't be negative. So setAge changes age only when value is 0 or more. After rex.setAge(-5), the age stays as it was.

Why not a public field?

With a public age field, any code could set it to -5. Nothing would check it. The setter keeps the rule inside the class.

The names follow a Java habit. They are get or set, then the field name with a capital letter.

Your task

The Dog class keeps its age in the private field age. Add two public methods. The getter getAge() returns the age. The setter setAge(value) ignores negative values.

The code in mainFunction creates rex, then reads and sets its age.

Expected output:

Rex is 3
Rex is still 3
Rex is 4