Java - Looping Number Strings

Question

You all were so helpful yesterday in getting over my first hump in this problem that I wanted to see if there's a way I can modify my final product (Apologies if my formatting is off - Still trying to get indentations correct in my IDE.

import javax.swing.JOptionPane;

public class NumberLoops {

    public static void main(String[] args) {

        String strNum1;
        String strNum2;
        int intNum;
        boolean isValid = true;
        boolean isError = false;

        strNum1 = JOptionPane.showInputDialog ("Enter Number String");

        for (int i=0; i<strNum1.length(); i++) {
            char c = strNum1.charAt(i);
            if (c == '-'){
                JOptionPane.showMessageDialog(null, "Negative Digit Found - Enter Positive Numbers Only", "Error", JOptionPane.INFORMATION_MESSAGE);
                isValid = false;
                break;
            }
        }
        if (isValid){
            for (int i=0; i<strNum1.length(); i++) {
                char c = strNum1.charAt(i);
                intNum = Character.getNumericValue(c);{
                    if (intNum > 0 && intNum <= 9){
                        isError = true;
                        break;
                    }
                }
            }
        }
        if (isError){
            int aDigit,totalNum=0;
            char chDigit;
            strNum2 = String.valueOf(strNum1);
            for (int count=0; count<strNum1.length();count++){
                chDigit = strNum2.charAt(count);
                aDigit = Character.getNumericValue(chDigit);
                totalNum += aDigit;
                if (aDigit > 0 && aDigit <= 9){
                    System.out.print(aDigit + " ");
                }
            }
            System.out.print(" " + "The sum is: " + totalNum);
        }
    }
}

My question concerns the last loop. It functions as desired by printing to the console if I enter say 123123 into the message prompt, it lists that string as 1 2 3 1 2 3 and then the total of 12.

But that is in the console itself. What I'm trying to wrap my mind around is getting it to display in a message box instead of the console.

I'm guessing I need to create a new string like (incoming pseudocode):

if (aDigit > 0 && aDigit <= 9){
strNum3 = everycharinStr2 + " "

Which is the part I guess I'm not grasping.

FYI, this is a homework assignment so I don't necessarily want an outright answer, but I feel I am so close that I need some extra eyes on it to see if there's anything I can do. (I have read up on arrays and such but we aren't at that point yet so I don't think I'll go down that road quite yet.)

Answer 1

You only have to make a little change in your code:

        strNum2 = String.valueOf(strNum1);
        String resultString = "";
        for (int count=0; count<strNum1.length();count++){
            chDigit = strNum2.charAt(count);
            aDigit = Character.getNumericValue(chDigit);
            totalNum += aDigit;
            if (aDigit > 0 && aDigit <= 9){
                System.out.print(aDigit + " ");
                resultString += aDigit + " ";
            }
        }
        JOptionPane.showMessageDialog(null, resultString);

Create a new String and in each iteration append the number to this String , then show it in a dialog.

Answer 2

The errors are commented out.

                //if (intNum > 0 && intNum <= 9){
                if (intNum < 0 || intNum > 9){
                    isError = true;
                    break;
                }

        //if (aDigit > 0 && aDigit <= 9){
        if (aDigit >= 0 && aDigit <= 9){
            System.out.print(aDigit + " ");
            //resultString+ = aDigit + " ";
            resultString += "" + aDigit;
        }

//if (isError) {
if (!isError) {

Answer 3

Just use a JLabel !

Since your already using swing, this would be your best choice. But then you'd need a frame and panel, so if you don't already have that, don't do this.

JLabel label = new JLabel()
label.setText("Random Text!")

You can also do this, with a pop up:

JOptionPane.showMessageDialog(null, "My String!");