Java - Return multiple string user input in do while infinite loop

Question

How to print multiple Strings from Scanner as there is no array to call out and I'm stuck on how to generate the output.

My do-while loop will stop when user enters #. It seems fine until the part to print out the result, if I put the strResult I can only see the last string of user input.

Below is my current code :

import java.util.Scanner;
public class SecretMessage {

    public static void main(String[] args) {
        int count =0;
        int i =0;
        //char ch;<<<<<<<<<< I need this for converting the string to char
        Scanner sc = new Scanner(System.in);
        //String result[] = new String[count];<<<<<<<<purposedly for array 
        String input ="";
        String strResult ="";


        do  {
            System.out.print("Enter your text :");
            input=sc.nextLine();
            count++;
        }

        while (!input.equals("#"));
        {
            System.out.print("Result :\n");

            strResult = "Case #"+(count-1)+" :"+input;
            //result[count] = strResult;<<<<<<to represent all result
        }       

        for (i=0;i<(count-1);i++) {

            System.out.println(" "+strResult);

        }
    }
}

I'm not sure what you're trying to do, to print each of the Strings read in order? But using an array? Or by **not** using it? — Frakcool, Oct 03 '17 at 22:05
"as there is no array" - is there something blocking you from creating one? Btw: as you can not know the number of lines beforehand, an ArrayList may be a better choice. — tevemadar, Oct 03 '17 at 22:06
To @Frakcool -Yes, I need to print each of the Strings entered in order. I don't know how the array works in this do-while cases but in For loop I know how the array works. — Aliff, Oct 03 '17 at 22:23
TO @tevemadar - I still didn't understand how ArrayList works. As you can see in my coding, I to do something else with the input Strings before I can print out the results. For know I just need to get the result printed sequentially. — Aliff, Oct 03 '17 at 22:28

score 1 · Accepted Answer · answered Oct 03 '17 at 22:20

You can use an ArrayList

    ArrayList list = new ArrayList();


    do  {
       System.out.print("Enter your text :");
       input=sc.nextLine();
       list.add(input);
       count++;
       }

   while (!input.equals("#"));
{
       System.out.print("Result :\n");

       strResult = "Case #"+(count-1)+" :"+input;
       //result[count] = strResult;<<<<<<to represent all result
       }       

   for (i=0;i<list.size()-1;i++) {

       System.out.println("Case #" +  (i+1) + " " + list.get(i));

   }

WilliamNHarvey · Answer 2 · 2017-10-03T22:44:33.043

0

Use StringBuilder: In Java, how to append a string more efficiently?

    StringBuilder stringBuilder = new StringBuilder();

    do  {
        System.out.print("Enter your text :");
        input=sc.nextLine();
        stringBuilder.append(input);
        count++;
    }

    while (!input.equals("#"));
    {
        System.out.print("Result :\n");

        strResult = "Case #"+(count-1)+" :"+stringBuilder.toString();
        //result[count] = strResult;<<<<<<to represent all result
    }

edited Oct 03 '17 at 22:44

answered Oct 03 '17 at 22:08

WilliamNHarvey

2,335
2
17
26

If I use StringBuilder, how to stop the loop? As you can see that my while expression is already initialized with input – Aliff Oct 03 '17 at 22:34
i missed that, you can still update input as the last read line and append the variable to stringbuilder – WilliamNHarvey Oct 03 '17 at 22:45
Oh I see. Thanks! – Aliff Oct 03 '17 at 22:47

Java - Return multiple string user input in do while infinite loop

2 Answers2