CODEWITHSUNDEEP
javaarraysobjectindexoutofboundsexception
Whoppa
Whoppa

Reputation: 999

Getting ArrayIndexOutOfBoundsException and not sure why

I am learning about object oriented concepts right now. I wrote a simple class to accept user input scores but I am getting an out of bounds exception and I'm not sure why! I don't see why this would be accessing indexes over than 4? Here is the code:

The HighScores class which I am instantiating 5 objects into an array:

public class HighScores
{
    String name;
    int score;

    public HighScores()
    {
        this.name = "";
        this.score = 0;
    }
    public HighScores(String name, int score)
    {
        this.name = name;
        this.score = score;
    }

    void setName(String name)
    {
        this.name = name;
    }

    String getName()
    {
        return this.name;
    }

    void setScore(int score)
    {
        this.score = score;
    }

    int getScore()
    {
        return this.score;
    }
}

The program manipulating HighScore objects:

import java.util.Scanner;

public class HighScoresProgram
{

    public static void main(String[] args)
    {
        HighScores[] highScoreObjArr = new HighScores[5];

        for (int i = 0; i < highScoreObjArr.length; i++)
        {
            highScoreObjArr[i] = new HighScores();
        }
        initialize(highScoreObjArr);
        sort(highScoreObjArr);
        display(highScoreObjArr);
    }

    public static void initialize(HighScores[] scores)
    {
        Scanner keyboard = new Scanner(System.in);
        for(int i = 0; i < scores.length; i++)
        {
            System.out.println("Enter the name for for score #" + (i+1) + ": ");
            String temp = keyboard.next();
            scores[i].setName(temp);
            System.out.println("Enter the the score for score #" + (i+1) + ": ");
            scores[i].setScore(keyboard.nextInt());
        }

    }

    public static void sort(HighScores[] scores)
    {
        for(int i = 0; i < scores.length; i++)
        {
            int smallest = i;

            for (int j = i; i < scores.length; i++)
            {
                if (scores[j].getScore() < scores[smallest].getScore())
                    smallest = j;
            }

            HighScores temp = scores[i];
            HighScores swap = scores[smallest]; //This is where I'm getting the out of bounds exception.
            scores[i] = swap;
            scores[smallest] = temp;

        }
    }

    public static void display(HighScores[] scores)
    {
        System.out.println("Top Scorers: ");
        for(int i = 0; i < scores.length; i++)
        {
            System.out.println(scores[i].getName() + ": " + scores[i].getScore());
        }

    }

}

Upvotes: 1

Views: 129

Answers (5)

user2875451
user2875451

Reputation: 1

for (int j = i; j < scores.length; j++)

Upvotes: 0

Edward
Edward

Reputation: 319

 for (int j = i; i < scores.length; i++)

You're incrementing i instead of j here.

Upvotes: 2

MaD
MaD

Reputation: 880

I think that the problem is when the loop ends it means that i is no longer smaller then scores.length. which means that you are basically checking the of bound when you exit the loop below the line:

for (int j = i; i < scores.length; i++)

Upvotes: 2

Crickcoder
Crickcoder

Reputation: 2155

The problem here is that you are incrementing same vairable i in outer and inner loop. Your outer loop runs 4 times but inner loop increments the value if i further. Use a different variable in inner for loop

Upvotes: 0

upog
upog

Reputation: 5526

i guess below line is issue

for (int j = i; i < scores.length; i++)

try updating sort function as below

 public static void sort(HighScores[] scores)
    {
        for(int i = 0; i < scores.length; i++)
        {
            int smallest = i;

            for (int j = i; j < scores.length; j++)
            {
                if (scores[j].getScore() < scores[smallest].getScore())
                    smallest = j;
            }

            HighScores temp = scores[i];
            HighScores swap = scores[smallest]; //This is where I'm getting the out of bounds exception.
            scores[i] = swap;
            scores[smallest] = temp;

        }
    }

Upvotes: 5

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