Create an application that is composed of at least 2 classes in addition to the startup class.One of the classes is to be a subclass derived from the other. The subclass is to have at least 3 constractors which will be called during the creation of 3 subclass objects.In the example shown, the subclass student has a default constractor, a constractor with one string argument, and a constractor with a string argument
giving the student's name and integer argument giving an ID number. (File must be save as: Assigment06.java)

import javax.swing.JOptionPane;
class Startup
{
            public String n;
            public int r;
}
class Sub extends Startup
{
            Sub()
            {
                        //JOptionPane.showMessageDialog(null,"For default constructor\n");
                        n="Blank name";
                        r=0;
            }
            Sub(String s)
            {
                        //JOptionPane.showMessageDialog(null,"For one string constractor\n");
                        n=s;
                        r=0;
            }
            Sub(String s,int a)
            {
                        n=s;
                        r=a;
            }
            void print()
            {
                        JOptionPane.showMessageDialog(null,"Name : "+n+"\nRoll : "+r);
            }
}
class Assigment06
{
            public static void main(String args[])
            {
                        Sub a,b,c;
                        String s1,s2;
                        int n;
                        a=new Sub();
                        a.print();
                        s1=JOptionPane.showInputDialog("Name : ");
                        b=new Sub(s1);
                        b.print();

                        s1=JOptionPane.showInputDialog("Name : ");
                        s2=JOptionPane.showInputDialog("Roll : ");
                        n=Integer.parseInt(s2);
                        c=new Sub(s1,n);
                        c.print();
                        System.exit(0);
            }
}


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Copy & paste this code in your TC & run, then you will get output.......
If you have any problem please comment below.........