Trouble with instantiating inherited classes in a switch statement

Question

Hi
I have few inherited classes which I need to instantiate in a switch statement based on command line argument supplied by user. I am ble to do that but I cannot access any methods once I come out of the switch scope. Please suggest a way to resolve this problem. The error I am getting is in the end of code in comments // //. Would really appreciate your help.
Thanks
Here is the code.
package assignment2;
import java.util.*;
import java.io.*;
abstract class Parent
abstract void childclassDescription();
void generalDescriptionToAllChilds()
System.out.println("general to all child classes");
childclassDescription();
class Child1 extends Parent
public void childclassDescription()
System.out.println("i'm child1");
class Child2 extends Parent
public void childclassDescription()
System.out.println("i'm child2");
class Child3 extends Parent
public void childclassDescription()
System.out.println("i'm child3");
public class Demo
public static void main(String[] args)
int option;
Parent p;
System.out.println("Pick from one of the following:");
option=1; // supplying
switch(option)
case 1:
p=new Child1();
break;
case 2:
p=new Child2();
break;
case 3:
p=new Child3();
default:
break;
p.generalDescriptionToAllChilds();
//error variable p might not have been initialized at line //
}

Answer 1

Well I also think that in Java, it is possible for a reference type variable to refer to nothing at all. A reference that refers to nothing at all is called a null reference . By default, an uninitialized reference is null.
We can explicitly assign the null reference to a variable like this:
f = null;
But still i am not quety sure why you needed to do it.