Doubt related to Garbage Collection Questions

[Aditi Roychoudhury]

Hi All,

This is a question from Devaka's final exam.

How many objects are eligible for GC after line 17?

1. class A{
2. A a1;
3. A a2;
4. public void finalize(){
5. System.out.println("A");
6. }
7. public static void main(String args[]){
8. A a1=new A();
9. A a2=new A();
10. a1.a1=new A();
11. a2.a2=new A();
12. a1.a2=new A().a1;
13. a2.a1=a1;
14. a2.a1.a2=new A();
15. a1.a1.a1=new A();
16. a1=null;
17. a2=null;
18. System.gc();
19. }

The answer is 7.

Can someone tell me how should we work out these types of questions related to GC?

[Alexander Danilou]

5 minutes drawing circles reperesnting objects and arrows representing references and you will figure it out.
But I wonder - do they have questions like this on the real exam?

[Aditi Roychoudhury]

Alexander,

Thanks for the reply.

Can anyone confirm if questions of this type are present in the SUN exam?Also,any different approach to tackle this question?

Thanks,
Aditi.

[David Marco]

Alexander advice is a very good advice to tackle this kind of questions.

Greetings.

[James Tharakan]

Once you see such a question get ready with a pen and paper. draw the diagram then these question are very simple.
In the actually exam i dont think such a complex question will not be given, but a simple question would be given.But expect the unexpected.
Remember diagram solves the even a complex question