to make it a bit more clear, here is what i want to do (and i am hoping the Object data type can help me with it):

i am working on a game with multiple different objects. when i move the mouse over one of these objects, i want to store a reference to this object in some way. i was hoping, that i could use the Object data type as a sort of blank sheet for all my objects.

something like this is what i had in mind

1. class TestClass {  // empty example class
   
2.       TestClass(){
3.       }
4.       void doSomething(){
5.       }
   
6. }
7. 
   
8. // create instance of example class
9. TestClass testObject = new TestClass();
10. 
    
11. // create instance of Object. i want to store testObject here
    
12. Object myObject;
13. 
    
14. // put testObject into myObject
    
15. myObject = testObject;
16. 
    
17. // reference specific testClass related methods and fields with the Object instance
18. myObject.doSomething;
    

The Object class is the root, the most basic class in Java. That means that every class inherits from Object class no matter you point it explicitly or not. This class provides a few things:

it provides a few common methods available for all instances of all classes in Java like: clone, toString, equals etc.

it provides a common type for all classes in your code which is very imprtant for collections like ArrayList. You can have such collection because all the objects stored in ArrayList are casted to Object type, so you can do this:

1.  ArrayList aList = new ArrayList();
2. 
   
3. aList.add( 3 );
4. aList.add( "Sth" );
5. aList.add( createFont( "Tahoma", 10 ) );  // it returns and adds a PFont object
   

thank you trzewiczek, i think i understand what the Object class does now and that it won't do what i hoped for.
i posted some pseudocode, because my project is allready very complex and posting the real code would really be an overkill, even if i only had posted the relevant parts regarding this issue :)

Maybe the topic https://forum.processing.org/topic/code-structure-oop-inheritance can provide some inspiration...