public class ProuductList {
  private ArrayList<String> productList = new ArrayList<>;

  public void populateList() {
    productList.add("123");
    productList.add("456");
  }

  public ArrayList<String> getProductList() {
      return productList;
  }
}

public class InvenDriver {
  private ProductList productList;

  public InvenDriver() {
    productList = new ProductList();
    productList.populateList();
    //To use the list productList.getProductList();
  }
}