Java - Reading from an ArrayList from another class

Question

We\'ve not covered ArrayLists only Arrays and 2D arrays. What I need to do is be able to read from an ArrayList from another class. The main aim is to read from them in a fo

Answer 1

Strictly speaking, the exception is due to indexing location 1 of an ArrayList with 0 elements. Notice where you start you for loop index variable x. But consider this line:

ArrayList  xcoords = new ArrayList();

xcoords points to a new, empty ArrayList, not the one you created in class Objects. To get that ArrayList, change the method xco like

public ArrayList xco() { // make sure to parameterize the ArrayList
    ArrayList xcoords = new ArrayList();

    // .. add all the elements ..

    return xcoords;
}

then, in your main method

public static void main(String [] args) { // add correct arguments

    //..
    ArrayList  xcoords = (new Objects()).xco();

    for( int x = 0 ; x < xcoords.size() ; x++ ) { // start from index 0
        System.out.println(xcoords.get(x));
    }
}