Array output - remove the null [duplicate]

Question

I plan to print a message to show the result of data in the array. It suppose to look like
"7 *******" but I got a "7 null*******" instead.

I want to get rid of the "null"

import java.util.ArrayList;    

public class FavorGameDisplay
{
private ArrayList<String> votedGame;
private String[] asterisk;
private int[] gameCount;


/**
 * Constructor for objects of class FavorGameDisplay
 */
public FavorGameDisplay()
{
    FavorGameData data = new FavorGameData();
    votedGame = data.getData();
    analyzeData();
}

/**
 * Analyze and recording counts of the following video games:
 * gameCount[0]: Nier: Automata
 * gameCount[1]: PlayerUnknown’s Battlegrounds
 * gameCount[2]: Wolfenstein 2: The New Colossus
 * gameCount[3]: Cuphead
 * gameCount[4]: any other video games
 */
private void analyzeData()
{
    gameCount = new int[5];
    asterisk = new String[5];
    for (String game : votedGame) 
    {
        if (game.equals("Nier: Automata")) 
        {
            gameCount[0]++;
            asterisk[0] += "*";
        }

        else if (game.equals("PlayerUnknown’s Battlegrounds")) 
        {
            gameCount[1]++;
            asterisk[1] += "*";
        }

        else if (game.equals("Wolfenstein 2: The New Colossus")) 
        {
            gameCount[2]++;
            asterisk[2] += "*";
        }           


        else if (game.equals("Cuphead")) 
        {
            gameCount[3]++;
            asterisk[3] += "*";
        }
        else
        {
            gameCount[4]++;
            asterisk[4] += "*";
        }
    }           
}





/**
 * Display the analyzed data as a histogram
 */
public void displayData()
{

    System.out.println("------------------------------------------");
    System.out.println("Number of people vote for each game: ");        
    System.out.println("Nier: Automata:   " + gameCount[0] + " " + asterisk[0]);
    System.out.println("PlayerUnknown’s Battlegrounds:  " + gameCount[1] + " " + asterisk[1]);
    System.out.println("Wolfenstein 2: The New Colossus:    " + gameCount[2] + " " + asterisk[2]);         
    System.out.println("Cuphead: " + gameCount[3] + " " + asterisk[3]);  
    System.out.println("Others: " + gameCount[4] + " " + asterisk[4]);  
    System.out.println("------------------------------------------");
}
}

For starters, you're using parallel arrays; you should instead have a class Game and a List<Game>. — chrylis -cautiouslyoptimistic-
– chrylis -cautiouslyoptimistic-, Commented Nov 30, 2017 at 0:00
@chrylis nah, you don't need to do anything that complicated. You can just do String.join("", Collections.nCopies(count, "*")) when you want to print the asterisks; and store the counts in a Map<String, Integer>. — Andy Turner
– Andy Turner, Commented Nov 30, 2017 at 0:09

Andy Turner · Accepted Answer · 2017-11-30 00:03:33Z

2

You don't initialize the elements of asterisk first; so when you write:

asterisk[0] += "*";

you concatenate the string representation of its current value (null) with "*", so you end up with null*.

Fill the array with empty strings before the loop:

Arrays.fill(asterisk, "");

answered Nov 30, 2017 at 0:03

Andy Turner

141k11 gold badges169 silver badges263 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Array output - remove the null [duplicate]

1 Answer 1

Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Linked

Related