How to create an empty array?

You cannot make an empty array and then let it grow dynamically whenever the user enters a number in the command line. You should read the numbers and put them in an ArrayList instead. An ArrayList does not require a initial size and does grow dynamically. Something like this:

public void main(String[] args) {
    ArrayList<Integer> numbers = new ArrayList<Integer>();
    BufferedReader console = 
            new BufferedReader(new InputStreamReader(System.in));
    while(true) {
        String word = console.readLine();
        if (word.equalsIgnoreCase("end") {
            break;
        } else {
            numbers.add(Integer.parseInt(word);
        }
    }

Ofcourse you won’t use while(true)and you won’t put this in main, but it’s just for the sake of the example