How is xml being used for a game engine

Question

In this question the first answer explains a way of defining components of a gaming engine in xml like this:

<?xml version="1.0" encoding="UTF-8"?>
<mobs>
  <mob>
    <personality>Aggressive</personality>
    <intelligence>20</intelligence>
  </mob>
</mobs>

and then states in java your mob class would look like:

public class Mob {
  private IPersonality personality;
  private Integer intelligence

  //**  Getters & Setters **//
}

what exactly is the xml doing here?

I'm not really familiar with xml at all so if it appears like i dont know what im talking about then just point out of edit my stupidity out.

Answer 1

The XML describes one instance of a mob, i.e. the traits of one specific mob (it's personal personality and intelligence).

The Java class describes the general structure of all mobs (their traits: personality and intelligence).

Typically, a game engine would serialize the XML data at runtime to create actual Java Mob objects (= instances of the Mob class).

Answer 2

Maybe I didn't explain fully,

You implement the loading of the XML to the Class instance ensuring meaning in theory it could just as easily be any data format, json, flat file, Database its how you use the data that decides what it means. The example i provided was instantiating a new instance of IPersonality based on the String within the tags

 public IPersonality getPersonality(String personalityName) {
      if(personalityName.equals("Aggressive")) {
        return new AggressivePersonality();
      }
      else if(personalityName.equals("Passive")) {
        return new PassivePersonality();
      }
      else {
         //Maybe allow for no personality (We all know monster like that ;) )
         return null; 
      }
    }

Here I saying if I find the name aggressive this mob the aggressive personality component.