When do instance variables get initialized and values assigned?
- by AKh
When doees the instance variable get initialized? Is it after the constructor block is done or before it?
Consider this example:
public abstract class Parent {
public Parent(){
System.out.println("Parent Constructor");
init();
}
public void init(){
System.out.println("parent Init()");
}
}
public class Child extends Parent {
private Integer attribute1;
private Integer attribute2 = null;
public Child(){
super();
System.out.println("Child Constructor");
}
public void init(){
System.out.println("Child init()");
super.init();
attribute1 = new Integer(100);
attribute2 = new Integer(200);
}
public void print(){
System.out.println("attribute 1 : " +attribute1);
System.out.println("attribute 2 : " +attribute2);
}
}
public class Tester {
public static void main(String[] args) {
Parent c = new Child();
((Child)c).print();
}
}
OUTPUT:
Parent Constructor
Child init()
parent Init()
Child Constructor
attribute 1 : 100
attribute 2 : null
When the memory for the atribute 1 & 2 are allocated in the heap ?
Curious to know why is attribute 2 is NULL ?
Are there any design flaws?
