@Test
 public void testSlice() {
   Slice sl;
   sl = new Slice();
   assertEquals(":", sl.toString());
   sl = new Slice(12);
   assertEquals(":12", sl.toString());
   sl = new Slice(1, 12);
   assertEquals("1:12", sl.toString());
   sl = new Slice(0, 12);
   assertEquals(":12", sl.toString());
   sl = new Slice(null, 12);
   assertEquals(":12", sl.toString());
   sl = new Slice(11, 12);
   assertEquals("11", sl.toString());
   sl = new Slice(1, 12, 3);
   assertEquals("1:12:3", sl.toString());
   sl = new Slice(11, 12, 3);
   assertEquals("11", sl.toString());
   sl = new Slice(0, 12, 3);
   assertEquals(":12:3", sl.toString());
   sl = new Slice(1, 12).setLength(12);
   assertEquals("1:", sl.toString());
   sl = new Slice(1, null).setLength(12);
   assertEquals("1:", sl.toString());
   sl = new Slice(0, 12).setLength(12);
   assertEquals(":", sl.toString());
   sl = new Slice(1, 12, 3).setLength(12);
   assertEquals("1::3", sl.toString());
   sl = new Slice(0, 12, 3).setLength(12);
   assertEquals("::3", sl.toString());
   sl = new Slice(null, null, 3).setLength(12);
   assertEquals("::3", sl.toString());
   sl = new Slice(11, 12);
   assertEquals("11", sl.toString());
   sl = new Slice(0, 1);
   assertEquals("0", sl.toString());
   sl = new Slice(1);
   assertEquals("0", sl.toString());
 }