First Element of String array printing null

Question

First element of string array printing null. Please explain why it is not printing the first element of string array.

public static void main(String[] args) throws Exception {
    Scanner s = new Scanner(System.in);

    String[] array = new String[aa];
    System.out.println("Please enter 20 names to sort");
    for (int i = 0; i < array.length; i++) {
        array[i] = s.nextLine();
    }
    System.out.println(array[0]);

}

Answer 1

The problem is that you are not giving a valid integer when constructing the String array. Instead of aa , you should have a number. Since you ask for 20 names, then you should declare an array of size 20.

Edit: Assuming aa is user input, you just need to consume the next line after reading. Note that this also happens when using nextDouble with the scanner.

public static void main(String[] args) throws Exception 
{
    Scanner s = new Scanner(System.in);
    System.out.println("How many names would you like to enter?");
    int aa = s.nextInt();
    //must include since nextInt leaves the new line
    s.nextLine();
    String[] array = new String[aa];
    System.out.println("Please enter " + aa + " names to sort");
    for (int i = 0; i < array.length; i++) 
    {
        array[i] = s.nextLine();
    }
    System.out.println(array[0]);

}

Also, please note that the array will not sort itself! You'll have to implement that later.