Below mentioned piece of code gives output as "Stack overflow error". Could someone please explain the code?

Question

class A
{
A a1=new A( );
public static void main(String [ ]args)
{
A a2=new A( );
}
}

Answer 1

'Thrown when a stack overflow occurs because an application recurses too deeply.'
From:
https://docs.oracle.com/javase/7/docs/api/java/lang/StackOverflowError.html

In your example, the instantiation can't be completed, before class A is fully instantiated.
To be completely instantiated, your class must create another instance of A (object a1). And that object must instantiate another object of A and so on and so on.

Answer 2

You're welcome ^^

Answer 3

thank you