Margins implements TagParameters { public boolean areVoid() { return this.all == null && this.top == null && this.right == null && this.bottom == null && this.left == null; } Margins(final Length all, final Length top, final Length right, final Length bottom,
            final Length left); boolean areVoid(); @Override void appendXMLContent(final XMLUtil util, final Appendable appendable); @Override boolean equals(final Object o); @Override String toString(); @Override int hashCode(); MarginsBuilder toBuilder();  }
@Test public final void testVoid() { final Margins margins = new MarginsBuilder().top(MarginsTest.TEN_PT).right(SimpleLength.pt(11.0)) .bottom(SimpleLength.pt(12.0)).left(SimpleLength.pt(13.0)).build(); Assert.assertFalse(margins.areVoid()); Assert.assertTrue(new MarginsBuilder().build().areVoid()); }