OOP AND ENCAPSULATION

Static Field Access and Class Initialization

Rule: Accessing a static field only initializes the class that declares the field, not the class through which it’s accessed.

Class initialization is triggered by accessing a field declared by that class.
Inherited static fields do not trigger subclass initialization.
The reference used (Child.familyName) doesn’t matter - only the declaring class matters.

class Parent { 
    static String familyName = "Johnson"; 
}

class Child extends Parent {
    static { 
        System.out.print("Child initialized"); 
    }
}

public class FamilyTest {
    public static void main(String[] args) {
        System.out.println(Child.familyName);  // Accesses inherited field
    }
}

// Output: Johnson
// NOT: Child initializedJohnson

💡 Learning Tip: Remember “DECLARES WINS” - only the class that declares the static field gets initialized, even when accessed through a subclass reference.

Q: Does accessing Child.familyName initialize the Child class if familyName is declared in Parent?
A: No — only Parent gets initialized because Parent declares the field. Child inherits it but doesn’t declare it.