Does anybody know what method exists() really do?

[VladX 0]

I wonder what method calling on entities exactly do, becouse i recently noticed that Rocks can not exists (on method) while i see that rocks with specific ore (on screen).

I think about:

 

GameObject obj = getGameObjects().closest("Rocks");

if(obj.exists()){

interaction things;

} else {

log("Object "+obj.getTile()+" doesnt exists); // <--- i saw that it exists, 100% sure

}

i notice that issue with oak tree but i think its doesnt matter on wchich object i notice it. So what this methot exactly do?