Vfrdtyky

I am trying to print out a 2 dimentional array in a messagedialog using JOptionPane. I am supposed to create a method that converts the array to a string using a for-loop. I have tried a lot, but it doesn't seem to get the logic working as i want it to. This is what i have so far.

public static String toString(int array) {

        String res = "{";

        for (int i = 0; i < array.length; i++) {

            for (int j = 0; j <array[i].length; j++) {

                res += array[i][j];

                if(j < array.length-1) {

                    res += ","; 

                }

                if (i < array.length-1) {

                    res += "}";

                }



            }



        }res += "}";

        return res;

    }

Main class:

import javax.swing.JOptionPane;



import arrays.Integer2dArrays;



public class Exercise4b {

    public void testArray(int array) {

        String message = "";

        message += "toString: " + Integer2dArrays.toString( array ) + "n";

        message += "elements: " + Integer2dArrays.elements( array ) + "n";

        message += "max: " + Integer2dArrays.max( array ) + "n";

        message += "min: " + Integer2dArrays.min( array ) + "n";

        message += "sum: " + Integer2dArrays.sum( array ) + "n";

        message += "average: " + String.format( "%1.2f", Integer2dArrays.average( array ) ) + "n";

        JOptionPane.showMessageDialog( null, message );

    }



    public static void main(String args) {

        Exercise4b e4b = new Exercise4b();

        int test1 = {{1,2,3,4},{-5,-6,-7,-18},{10,9,8,7}};

        int test2 = {{1,2,3,4,5,6},{-7,-8,-9},{2,5,8,11,8},{6,4}};

        e4b.testArray(test1);

        e4b.testArray(test2);        

    }

}

The end result should look like this:

The common logic you are missing is the

    if (i > 0)

            res += ",";

So to get it correctly your method toString should be like this:

  public static String toString(int array) {

    String res = "{";

    for (int i = 0; i < array.length; i++) {

        if (i > 0)

            res += ",";

        res += "{";

        for (int j = 0; j <array[i].length; j++) {

             if (j> 0)

                res += ",";

            res += array[i][j];

        }

      res += "}";



    }

    res += "}";

    return res;

}

Maybe you can use deepToString to achieve your result ?

String result = Arrays.deepToString(test1)

            .replace("[", "{")

            .replace("]", "}")

            .replace(" ", "");