Declaring an instance of a class inside that class

Question

This code shows error at run time:

class Animal {
    Animal object1 = new Animal();

    public static void main(String[] args) {     
        Animal obj =          


        

Answer 1

It's a stack overflow.

It's similar to calling a function from the same function, like this:

void func(){
  func();
}

It will repeat until the stack fills, and then the program will crash.

Cheers.