### Question:
CategoryLabelPositions implements Serializable { @Override public int hashCode() { int result = 19; result = 37 * result + this.positionForAxisAtTop.hashCode(); result = 37 * result + this.positionForAxisAtBottom.hashCode(); result = 37 * result + this.positionForAxisAtLeft.hashCode(); result = 37 * result + this.positionForAxisAtRight.hashCode(); return result; } CategoryLabelPositions();  CategoryLabelPositions(CategoryLabelPosition top,
                                  CategoryLabelPosition bottom,
                                  CategoryLabelPosition left,
                                  CategoryLabelPosition right); static CategoryLabelPositions createUpRotationLabelPositions(
            double angle); static CategoryLabelPositions createDownRotationLabelPositions(
            double angle); CategoryLabelPosition getLabelPosition(RectangleEdge edge); static CategoryLabelPositions replaceTopPosition(
            CategoryLabelPositions base, CategoryLabelPosition top); static CategoryLabelPositions replaceBottomPosition(
            CategoryLabelPositions base, CategoryLabelPosition bottom); static CategoryLabelPositions replaceLeftPosition(
            CategoryLabelPositions base, CategoryLabelPosition left); static CategoryLabelPositions replaceRightPosition(
            CategoryLabelPositions base, CategoryLabelPosition right); @Override boolean equals(Object obj); @Override int hashCode(); static final CategoryLabelPositions STANDARD; static final CategoryLabelPositions UP_90; static final CategoryLabelPositions DOWN_90; static final CategoryLabelPositions UP_45; static final CategoryLabelPositions DOWN_45; }### Answer:
@Test public void testHashCode() { CategoryLabelPositions p1 = new CategoryLabelPositions( new CategoryLabelPosition(RA_TOP, TextBlockAnchor.CENTER), new CategoryLabelPosition(RA_TOP, TextBlockAnchor.CENTER), new CategoryLabelPosition(RA_TOP, TextBlockAnchor.CENTER), new CategoryLabelPosition(RA_TOP, TextBlockAnchor.CENTER)); CategoryLabelPositions p2 = new CategoryLabelPositions( new CategoryLabelPosition(RA_TOP, TextBlockAnchor.CENTER), new CategoryLabelPosition(RA_TOP, TextBlockAnchor.CENTER), new CategoryLabelPosition(RA_TOP, TextBlockAnchor.CENTER), new CategoryLabelPosition(RA_TOP, TextBlockAnchor.CENTER)); assertEquals(p1, p2); int h1 = p1.hashCode(); int h2 = p2.hashCode(); assertEquals(h1, h2); }