public interface CategoryURLGenerator {

    /**
     * Returns a URL for one item in a dataset. As a guideline, the URL 
     * should be valid within the context of an XHTML 1.0 document.  Classes
     * that implement this interface are responsible for correctly escaping
     * any text that is derived from the dataset, as this may be user-specified
     * and could pose a security risk.
     *
     * @param dataset  the dataset.
     * @param series  the series (zero-based index).
     * @param category  the category.
     *
     * @return A string containing the URL.
     */
    public String generateURL(CategoryDataset dataset, int series, 
            int category);