Keyword

  abstract class Person
  {
    private String name,city;
    public Person(String nm,String ct)
    {
        name=nm;
        city=ct;
    }
    public void showData()
    {
        System.out.println("name is "+name);
        System.out.println("City is "+city);
    }
  }
  class Student extends Person
  {
    private int rollno;
    public Student(int rn,String nm,String ct)
    {
        super(nm,ct);
        rollno=rn;
    }
    public void showData()
    {
        System.out.println("rollno is "+rollno);
        super.showData();
    }
  }
  class demo
  {
    public static void main(String args[])
    {
        Person a=new Person("Nitin","Nagpur");
        a.showData();
        Student b=new Student(4117 ,"amit jain","Amravati");
        b.showData();
    }
  }

  abstract class Person
  {
    private String name,city;
    public Person(String nm,String ct)
    {
        name=nm;
        city=ct;
    }
    public abstract void showData();
  }
  class Student extends Person
  {
    private int rollno;
    public Student(int rn,String nm, String ct)
    {
        super(nm,ct);
        rollno=rn;
    }
    public void showData()
    {
        System.out.println("rollno is "+rollno);
        System.out.println("name is "+name);
        System.out.println("city is "+city);
    }
  }
  class demo
  {
    public static void main(String args[])
    {
        Student a=new Student(4117,"amit jain","Amravati");
        a.showData();
    }
  }