//Course. javaimport java. util\.\*; import java. io\.\*; public class Course { private ArrayList roster; // Collection of Student objects public Course() { roster = new ArrayList(); } public int courseSize() { /* Your code goes here */ } public void addStudent(Student s) { roster. add(s); } // main public static void main(String[] args) { Course course = new Course(); String first; // first name String last; // last name double gpa; // grade point average first = ""Bo""; last = ""Lang""; gpa = 3.1; course. addStudent(new Student(first, last, gpa)); // Add 1st student first = ""Rahul""; last = ""Rose""; gpa = 2.8; course. addStudent(new Student(first, last, gpa)); // Add 2nd student first = ""Mariam""; last = ""Felix""; gpa = 3.7; course. addStudent(new Student(first, last, gpa)); // Add 3rd student System. out. println(""Course size: "" + course. courseSize()); // Expect: 3 } }