Java Code Removed Data From XML File

I tried working with XML today, since that's what my book teaches. First, I read some data about Product objects that are suppose to represent products with a code, description, and price. That worked fine. Then, I tried creating a writeProducts(ArrayList<Product> products) method, and man it did not go well.

How it works is that there is an ArrayList instance variable in the class that keeps track of all of my products after the readProducts method returns that ArrayList from the XML file. When I ran the method I had a lot of stack traces printed. I then checked the file on a web browser and an editor, and saw it was completely empty. Here's the code:

import java.util.ArrayList;
import java.io.*;
import javax.xml.stream.*; // StAX API
public class XMLTesterApp {
private static String productsFilename = "products.xml";
public static void main(String[] args) {
System.out.println("Products list:");

[Code] ....

Java Result: 1

BUILD SUCCESSFUL (total time: 0 seconds) mh_sh_highlight_all('java');

On a side note, is it normal if almost everything I writer has to be debugged?