constructor-injection-example.php

<?php

class user
{
    /**
     * @var
     */
    private $userPhone;

    /**
     * @var string
     */
    private $userName = '';

    /**
     * user constructor.
     * @param $userName
     * @param phone $userPhone
     *
     * Using the same phone object from the previous example we have injected an instance of the phone object 
     * into the constructor. Now when we instantiate this object later we will need to pass in an instance of the phone 
     * object. This means we no longer need to hard code the params from the phone object into this constructor.
     */
    public function __construct( $userName, phone $userPhone )
    {
        $this->userName = $userName;
        
        $this->userPhone =  $userPhone;
    }

    public function getUserName()
    {
        return $this->userName;
    }

    public function getUserPhone()
    {
        return $this->userPhone;
    }

}

$phone = new phone( 'HTC', 'One M8' );

$user = new user( 'Kenny', $phone );

echo '<pre>' . '<br>';

print_r( $user );

echo '<pre>';

****************************OUTPUT**********************************
user Object
(
    [userPhone:user:private] => phone Object
        (
            [brand:phone:private] => HTC
            [model:phone:private] => One M8
        )
    [userName:user:private] => Kenny
)