Encapsulation

<?php

class Person
{
    protected $name;
    protected $age;

    public function __construct($name)
    {
        $this->name=$name;
    }

    public function setAge($age)
    {
        if($age<18)
        {
            throw new Exception("Error Processing Request");

        }

        $this->age=$age;
    }

    public function getAge()
    {
        return $this->age;
    }


}


$asad=new Person('Asad');
$asad->setAge(20);
//$asad->age=2;
echo $asad->getAge();