Is there a way to program 100% object-oriented in PHP?

Question

I guess, it\'s possible to call functions in a separate class, I call this object-oriented programming in PHP.

But at the beginning, there is always an index.php or some

Answer 1

You need an entry point into your application somewhere. Java's entry point happens to be a predefined named location which is automatically called when an app starts. PHP's entry point is the first line of the first file that executes. As such, you need to get the ball rolling with a single "procedural" call somewhere, which could simply be something like:

require_once 'controller.php';
new Controller;

That's essentially the same thing Java does, just more explicitly.