### Question:
DateTick extends ValueTick { @Override public int hashCode() { return this.date.hashCode(); } DateTick(Date date, String label,
                    TextAnchor textAnchor, TextAnchor rotationAnchor,
                    double angle);  DateTick(TickType tickType, Date date, String label,
                    TextAnchor textAnchor, TextAnchor rotationAnchor,
                    double angle); Date getDate(); @Override boolean equals(Object obj); @Override int hashCode();  }### Answer:
@Test public void testHashCode() { Date d1 = new Date(0L); String l1 = "Label 1"; TextAnchor ta1 = TextAnchor.CENTER; DateTick t1 = new DateTick(d1, l1, ta1, ta1, Math.PI / 2.0); DateTick t2 = new DateTick(d1, l1, ta1, ta1, Math.PI / 2.0); assertEquals(t1, t2); int h1 = t1.hashCode(); int h2 = t2.hashCode(); assertEquals(h1, h2); }