Exercise 102 from Programming Part 1 from http://mooc.fi/

ExamScores.java

import java.util.ArrayList;

public class ExamScores{
	
	private ArrayList<Integer>	examScores;
	private int[]				gradeDistribution;
	
	public static void main(String[] args){
		ExamScores es = new ExamScores(34, 41, 53, 36, 55, 27, 43, 40);
		es.printDistribution();
		es.printAcceptancePercentage();
	}
	
	public ExamScores(int... scores){
		examScores = new ArrayList<Integer>();
		for (int score : scores){
			addScore(score);
		}
		gradeDistribution = new int[6];
	}
	
	public void addScore(int score){
		examScores.add(score);
	}
	
	public void printScores(){
		for (Integer score : examScores){
			System.out.println(score);
		}
	}
	
	public void howManyOfEachDistribution(){
		gradeDistribution = new int[6];
		for (int i = 0; i < examScores.size(); i++){
			if (50 <= examScores.get(i) && examScores.get(i) <= 60) {
				gradeDistribution[5]++;
			}
			else if (45 <= examScores.get(i) && examScores.get(i) <= 49) {
				gradeDistribution[4]++;
			}
			else if (40 <= examScores.get(i) && examScores.get(i) <= 44) {
				gradeDistribution[3]++;
			}
			else if (35 <= examScores.get(i) && examScores.get(i) <= 39) {
				gradeDistribution[2]++;
			}
			else if (30 <= examScores.get(i) && examScores.get(i) <= 34) {
				gradeDistribution[1]++;
			}
			else if (0 <= examScores.get(i) && examScores.get(i) <= 29) {
				gradeDistribution[0]++;
			}
		}
		
	}
	
	public void printSingleDistribution(int arrayPlace){
		for (int j = 0; j < gradeDistribution[arrayPlace]; j++){
			System.out.print("*");
		}
	}
	
	public void printDistribution(){
		howManyOfEachDistribution();
		for (int x = 5; x >= 0; x--){
			System.out.print(x + ": ");
			printSingleDistribution(x);
			System.out.println();
		}
	}

	public void printAcceptancePercentage(){
		int total = 0;
		for (int examScore : examScores){
			if (examScore > 29) {
				total++;
			}
		}
		System.out.println("Acceptance percentage: " + (double) total / examScores.size() * 100);
	}
}

HowIWouldDoIt_ExamScores.java

import java.util.ArrayList;

public class ExamScores{
	
	private ArrayList<ArrayList<Integer>> scores;
	
	public static void main(String[] args){
		ExamScores es = new ExamScores(34, 41, 53, 36, 55, 27, 43, 40);
		es.printDistribution();
		es.printAcceptancePercentage();
	}
	
	public ExamScores(int... scores){
		this.scores = new ArrayList<ArrayList<Integer>>();
		for (int i = 0; i < 6; i++){
			this.scores.add(new ArrayList<Integer>());
		}
		for (int score : scores){
			addScore(score);
		}
	}
	
	public void addScore(int score){
		if (50 <= score && score <= 60) {
			scores.get(5).add(score);
		}
		else if (45 <= score && score <= 49) {
			scores.get(4).add(score);
		}
		else if (40 <= score && score <= 44) {
			scores.get(3).add(score);
		}
		else if (35 <= score && score <= 39) {
			scores.get(2).add(score);
		}
		else if (30 <= score && score <= 34) {
			scores.get(1).add(score);
		}
		else if (0 <= score && score <= 29) {
			scores.get(0).add(score);
		}
	}
	
	public void printScores(){
		for (ArrayList<Integer> scoreList : scores){
			for (int score : scoreList){
				System.out.println(score);
			}
		}
	}
	
	public void printSingleDistribution(int grade){
		for (int j = 0; j < scores.get(grade).size(); j++){
			System.out.print("*");
		}
	}
	
	public void printDistribution(){
		System.out.println(scores);
		for (int x = 5; x >= 0; x--){
			System.out.print(x + ": ");
			printSingleDistribution(x);
			System.out.println();
		}
	}

	public void printAcceptancePercentage(){
		int validScores = 0;
		int invalidScores = 0;
		for (ArrayList<Integer> scoreList : scores){
			if (scores.indexOf(scoreList) != 0) {
				validScores += scoreList.size();
			}
			else{
				invalidScores += scoreList.size();
			}
		}
		System.out.println("Acceptance percentage: " + (double) validScores / (validScores + invalidScores) * 100);
	}
}