@Test public void clearTest() { final RoaringBitmap rb = new RoaringBitmap(); for (int i = 0; i < 200000; i += 7) // dense rb.add(i); for (int i = 200000; i < 400000; i += 177) // sparse rb.add(i); final RoaringBitmap rb2 = new RoaringBitmap(); final RoaringBitmap rb3 = new RoaringBitmap(); for (int i = 0; i < 200000; i += 4) rb2.add(i); for (int i = 200000; i < 400000; i += 14) rb2.add(i); rb.clear(); Assert.assertEquals(0, rb.getCardinality()); Assert.assertTrue(0 != rb2.getCardinality()); rb.add(4); rb3.add(4); final RoaringBitmap andresult = RoaringBitmap.and(rb, rb2); final RoaringBitmap orresult = RoaringBitmap.or(rb, rb2); Assert.assertEquals(1, andresult.getCardinality()); Assert.assertEquals(rb2.getCardinality(), orresult.getCardinality()); for (int i = 0; i < 200000; i += 4) { rb.add(i); rb3.add(i); } for (int i = 200000; i < 400000; i += 114) { rb.add(i); rb3.add(i); } final int[] arrayrr = rb.toArray(); final int[] arrayrr3 = rb3.toArray(); Assert.assertTrue(Arrays.equals(arrayrr, arrayrr3)); }