object passing of class

class Demo{
	public int sum(int a,int b){
		return a+b;
	}
}
class Student1{
	public void show(){
		System.out.println("I love learning");
	}
}
class StudentDemo{
	//If you see that the formal parameter of a method is a class type (reference type), what is needed here is the class object
	public void method(Student1 s){
		s.show();
	}
}
public class ArrayTest {
	public static void main(String[] args){
	Demo d =new Demo();
	StudentDemo sd = new StudentDemo();
	//create student object
	Student1 s =new Student1();
	sd.method(s);//Give the address of s here
	}
}