final String[] columnNames = new String[cols];
if (horizontalDimensions.size() == 1) {
headersIncluded = true;
final CrosstabDimension horizontalDimension = horizontalDimensions.get(0);
final List<String> categories = horizontalDimension.getCategories();
columnNames[0] = "";
for (int i = 1; i < columnNames.length; i++) {
columnNames[i] = categories.get(i - 1);
}