Question

I have written a piece of code :

public class Child{
int y ;
private static final int z = getZ();

static {
    System.out.println("The value of z is "+z);
}

public int getX(){
    System.out.println("get x");
    return 10;
}

public int getY(){
    Child ch = new Child();
    System.out.println("get y");
    ch.y = getX();
    return y;
}

public static int getZ(){
    System.out.println("get z");
    return new Child().getY();
}

public Child(){
    System.out.println("Child constructor");
}


public static void main(String...args){
    Child ch = new Child();
    System.out.println("the value of z in main is "+z);
}
}

And the output is :

get z
Child constructor
Child constructor
get y
get x
The value of z is 0
Child constructor
the value of z in main is 0

Can anyone please explain me why the value of z is 0 and not 10 ?

EDIT:- Thanks everyone , I got the answer to my first question . I still have a doubt , as far as I know the static blocks are executed after the class is loaded and before the first object of the class is instantiated . Well then the SOP(“The value of z is “+z) should have been executed before SOP(“Child constructor”) ! Ain’t it ?

Answer 1

Look at getY():

public int getY(){
    Child ch = new Child();
    System.out.println("get y");
    ch.y = getX();
    return y;
}

The first three lines are irrelevant – they don’t change the value of y in this instance, which is what gets returned.

You’re creating an awful lot of pointless objects in frankly spaghetti code, called while initializing the same class that you’re constructing instances of. I suggest you try to keep your code a lot simpler than this. Static initializers should be avoided where possible to start with, let alone ones that go all round the houses to do no useful work.