Student Class

import java.util.ArrayList;
public class Student {

	private static int num = 0;
	private int studentNum;
	private String lastName;
	private double gpa;
	private static ArrayList<Student> students = new ArrayList<Student>();

	Student(String lastName, double gpa) {
		this.studentNum = num;
		num++;
		this.lastName = lastName;
		this.gpa = gpa;

		if(students.size() == 0) {
			students.add(this);
		} else {
			int c = 0;
			while(c < students.size() && lastName.compareTo(students.get(c).lastName) >= 0) {
				c++;
			}
			students.add(c, this);
		}

	}

	private int getNum() { return this.studentNum; }

	private String getLName() { return this.lastName; }

	private double getGPA() { return this.gpa; }

	public static ArrayList<Student> getList() { return students; }

	public static ArrayList<String> listToString() {
		ArrayList<String> names = new ArrayList<String>();
		for(Student element: students) {
			names.add(element.getLName());
		}
		return names;
	}

	public static ArrayList<Double> listToDouble() {
		ArrayList<Double> gpas = new ArrayList<Double>();
		for(Student element: students) {
			gpas.add(element.getGPA());
		}
		return gpas;
	}

	public static ArrayList<Integer> listToInt() {
		ArrayList<Integer> nums = new ArrayList<Integer>();
		for(Student element: students) {
			nums.add(element.getNum());
		}
		return nums;
	}

	public static double calcAverageGPA() {
		int sum = 0;
		int count = 0;
		for(Student element: students) {
			sum += element.getGPA();
			count++;
		}

		return sum / (double) count;
	}



}


public class StudentTester {

	public static void main(String[] args) {

		new Student("Andrew", (Math.random() * 2) + 2);
		new Student("Beatrice", (Math.random() * 2) + 2);
		new Student("Wilhelm", (Math.random() * 2) + 2);
		new Student("Frederick", (Math.random() * 2) + 2);
		new Student("Stephanie", (Math.random() * 2) + 2);
		new Student("Evelyn", (Math.random() * 2) + 2);

		System.out.println(Student.calcAverageGPA());
		System.out.println(Student.listToString());

	}

}