### Question:
BubbleXYItemLabelGenerator extends AbstractXYItemLabelGenerator implements XYItemLabelGenerator, PublicCloneable, Serializable { @Override public int hashCode() { int h = super.hashCode(); h = HashUtilities.hashCode(h, this.zFormat); h = HashUtilities.hashCode(h, this.zDateFormat); return h; } BubbleXYItemLabelGenerator();  BubbleXYItemLabelGenerator(String formatString,
            NumberFormat xFormat, NumberFormat yFormat, NumberFormat zFormat);  BubbleXYItemLabelGenerator(String formatString,
            DateFormat xFormat, DateFormat yFormat, DateFormat zFormat); NumberFormat getZFormat(); DateFormat getZDateFormat(); @Override String generateLabel(XYDataset dataset, int series, int item); @Override String generateLabelString(XYDataset dataset, int series, int item); @Override boolean equals(Object obj); @Override int hashCode(); static final String DEFAULT_FORMAT_STRING; }### Answer:
@Test public void testHashCode() { BubbleXYItemLabelGenerator g1 = new BubbleXYItemLabelGenerator(); BubbleXYItemLabelGenerator g2 = new BubbleXYItemLabelGenerator(); assertEquals(g1, g2); assertEquals(g1.hashCode(), g2.hashCode()); }