Visibility control in another package example in Java

// Program to  Visibility Control in Another Package.
// First File ( Base.java ) in package p1
package  p1;
public class  Base 
{
private int n_pri = 1;
int n_def = 2;
protected int n_pro = 3;
public int n_pub = 4;
public Base() 
{
 System.out.println("base constructor");
 System.out.println("n_pri = " + n_pri);
 System.out.println("n_def = " + n_def);
 System.out.println("n_pro = " + n_pro);
 System.out.println("n_pub = " + n_pub);
}
}
// Second File ( Derived.java ) in package p2 : 
package  p2;
class Derived2 extends  p1.Base
{
Derived2()
{
 System.out.println("derived other package constructor");
 // class only
 // System.out.println("n_pri = " + n_pri);
 // class or package only
 // System.out.println("n_def = " + n_def);
 System.out.println("n_pro = " + n_pro);
 System.out.println("n_pub = " + n_pub);
}
}
// Third File ( OtherPackage.java ) in package p2 
package  p2;
class OtherPackage 
{
OtherPackage() 
{
 p1.Base p = new p1.Base();
 System.out.println("other package constructor");
 // class only
 // System.out.println("n_pri = " + p.n_pri);
 // class or package only
 // System.out.println("n_def = " + p.n_def);
 // class, subclass or package only
 // System.out.println("n_pro = " + p.n_pro);
 System.out.println("n_pub = " + p.n_pub);
}
}
// Fourth File ( Demo.java ) in package p2
package p2;
public class  Demo 
{
public static void main(String args[ ]) 
{
 Derived2 ob1 = new Derived2();
 OtherPackage ob2 = new OtherPackage();
}
}

Output:
base constructor
n_pri = 1
n_def = 2
n_pro = 3
n_pub = 4
derived other package constructor
n_pro = 3
n_pub = 4
base constructor
n_pri = 1
n_def = 2
n_pro = 3
n_pub = 4
other package constructor
n_pub = 4