Understanding Access Specifiers in Java

package ch10.l2.pack1;

//Class A is in the 'pack1' package
public class A {
	private int privateVar = 1; // Accessible only within class A
	int defaultVar = 2; // Default access, accessible within the package
	protected int protectedVar = 3; // Accessible within the package and 
	// by subclasses of A, even if they are in different packages
	public int publicVar = 4; // Accessible from any other class

	public void display() {
		System.out.println("Private: " + privateVar);
		System.out.println("Default: " + defaultVar);
		System.out.println("Protected: " + protectedVar);
		System.out.println("Public: " + publicVar);
	}
}

//Class B is in the 'pack1'package and is a subclass of A
class B extends A {
	public void displayVars() {
		// System.out.println("Private: " + privateVar); 
	    // Compile-time error: cannot access privateVar
		System.out.println("Default: " + defaultVar); // Accessible
		System.out.println("Protected: " + protectedVar); // Accessible
		System.out.println("Public: " + publicVar); // Accessible
	}
}

package ch10.l2.pack2;

import pack1.A;

class C extends A {
	public void displayVars() {
		// System.out.println("Private: " + privateVar); 
	    // Compile-time error: cannot access privateVar
		// System.out.println("Default: " + defaultVar); // Not Accessible
		System.out.println("Protected: " + protectedVar); // Accessible
		System.out.println("Public: " + publicVar); // Accessible
	}
}
public class TestAccess {
    public static void main(String[] args) {
        A obj = new A();
        C objC=new C();
        // System.out.println(obj.privateVar); 
        // Compile-time error: privateVar has private access in A
        // System.out.println(obj.defaultVar); 
        // Compile-time error: defaultVar is not public in A; 
        // cannot be accessed from outside package
        // System.out.println(obj.protectedVar); 
        // Compile-time error: protectedVar has protected access in A
        System.out.println("Public Var: "+obj.publicVar); // Accessible
        objC.displayVars(); // Accessible
    }
}

Public Var: 4
Protected: 3
Public: 4