public class TestStudent { public static void main(String[] args) { // object is instance of a class int x; // x is a variable and it's type is int Student ram ; // ram is a variable and it's type is Student // When Ever We Create an Object it is call Constructor by default //ram = new Student(); ram = new Student(1001,"Ram","Java",(byte)21); // Has-a relationship ram.setAge((byte)22); ram.setRollno(1002); //ram.takeInput(1001, "Ram", "Java", (byte)21); /*ram.rollno = -1001; ram.name ="Ram"; ram.age=-12;*/ ram.print(); //System.out.println("Ram is "+ram+ " Ram HashCode is "+ram.hashCode()); //ram.rollno =1000; /*System.out.println("****************************************************"); Student shyam = new Student(); shyam.rollno = 1002; shyam.name="Shyam"; shyam.print();*/ /*System.out.println("Shyam is "+shyam+" Shyam HashCode is "+shyam.hashCode()); shyam.rollno =1001; System.out.println( "Rollno "+shyam.rollno ); System.out.println( "Name "+shyam.name ); System.out.println( "Course "+shyam.courseName ); System.out.println( "Age "+shyam.age);*/ } }