Student.java

public class Student implements Comparable<Student> {
    String fullName;
    String department;
    double gpa;

    /* Constructor: set initial values of the Student object */
    public Student(String fullName, String department, double gpa) {
        this.fullName = fullName;
        this.department = department;
        this.gpa = gpa;
    }

    /* Compare "this" student to "that" student (the other object) */
    public int compareTo(Student that) {                                // 1
        if (this.gpa > that.gpa) {                                      // 2
            return 1;                                                   // 2
        } else if (this.gpa < that.gpa) {                               // 3
            return -1;                                                  // 3
        } else {                                                        // 4
            return 0;                                                   // 4
        }
    }
}