public boolean equals(Object obj) {
        if (obj == this) {
            return true;   
        }
        if (obj instanceof DefaultBoxAndWhiskerCategoryDataset) {
            DefaultBoxAndWhiskerCategoryDataset dataset 
                    = (DefaultBoxAndWhiskerCategoryDataset) obj;
            return ObjectUtilities.equal(this.data, dataset.data);
        }
        return false;