CODEWITHSUNDEEP
java
user1924247
user1924247

Reputation: 171

input data is null even thought value is assigned to element

I'm having a problem with this code:

package Jensen;

import java.util.Scanner;

public class JensenUppgift7 {

    public static void main(String[] args)
    {
            Scanner scanner = new Scanner(System.in);
            String[] ord = new String[10];

            System.out.println("Hej och välkommen till mitt program. Det här programmet" +
                            " kommer fråga dig att mata in ord som du väljer och sedan skriva " +
                            "ut de i omvänd ordning.");

            for(int x = 0; x < ord.length; x++)
            {
                    System.out.println("Skriv ett ord. Avsluta programmet genom att skriva 'Sluta'");
                    String indata = scanner.next();

                    if(indata.compareTo("Sluta") == 0 || x == ord.length - 1)
                    {
                            for(int i = x; i >= 0; i--)
                                    if(i == 0)
                                            System.out.print(ord[i] + ".");
                                    else
                                            System.out.print(ord[i] + ", ");
                            break;
                    }
                    else
                            ord[x] = indata;
            }
    }
}

The program asks for ten strings or less and prints them out in reversed order. My problem is that the last input value that is going to be the first one printed out is equal to null when I iterate through the array. I'm not sure why. The rest of the inputs are printed out correctly.

Upvotes: 0

Views: 110

Answers (2)

Rohit Jain
Rohit Jain

Reputation: 213391

You are not assigning the last value to the array at all. The below if condition:

if(indata.compareTo("Sluta") == 0 || x == ord.length - 1)

becomes true when the value of x is ord.length - 1, which is the last index, and it doesn't reach the else block, where you are assigning the value to the array.

You don't need to have that 2nd condition in the if block. The for loop will take care of your indices. Just remove it.

Also you can use equals method instead of compareTo to check for equality. and since you are comparing the value from user input, I suggest you to do an ignore case comparison:

 if(indata.equalsIgnoreCase("Sluta"))

Actually I don't understand the logic of this if block, as you are starting to print the array based on this condition. But it's sure that, if you print the array there, it won't be fully filled. Since your messages are not in English, it hard to guess what are you trying to do. Is it some kind of exit condition? Generally you don't have an exit condition, when you are storing the user input in an array. You let the array indices decide when to stop.

I'll let you decide what you actually want, and after doing the required changes, you can run another for loop after the given for loop, to print the values in array in reverse.

Upvotes: 4

ps-aux
ps-aux

Reputation: 12174

The last element is left out from the input loop. Change the condition x == ord.length - 1 to x == ord.length.

Upvotes: 1

Related Questions