Aggregation in Java

/* program to show the concept of Aggregation */

package aggregation;

class Aggregation2
{
     int roll;
     String name;
     String branch;
     Aggregation2(int roll,String name,String branch)
     {
         this.roll=roll;
         this.name=name;
         this.branch=branch;
     }
     public int getRollNo()
     {
         return roll;
     }
      public String getBranch()
     {
         return branch;
     }
       public String getName()
     {
         return name;
     } 
}

class Child
{
    int marks;
    int age;
    Aggregation2 ag;
    Child(int m,int a,Aggregation2 t)
    {
        marks=m;
        age=a;
        ag=t;
    }
    public void show()
    {
        System.out.println("The roll number of the student is : "+ag.getRollNo());
        System.out.println("Name is : "+ag.getName());
        System.out.println("Branch is : "+ag.branch);
        System.out.println("Student Age is : "+age);
        System.out.println("Student marks is : "+marks);
    }
}
class MainClass
{
    public static void main(String[] args)
    {
        Aggregation2 a=new Aggregation2(21,"sanjay","cse");
        Child c=new Child(78,14,a);
        c.show();
    }
}

output