@Test
public void testContains() {

    IntSet intSet = new BitSetIntSet();
    intSet.add(Integer.valueOf(1));
    intSet.add(10);
    intSet.add(10);
    intSet.add(11);
    intSet.add(1025);
    assertTrue(intSet.contains(1));
    assertFalse(intSet.contains(2));
    assertFalse(intSet.contains(3));
    assertFalse(intSet.contains(4));
    assertTrue(intSet.contains(10));
    assertTrue(intSet.contains(11));
    assertFalse(intSet.contains(1024));
    assertTrue(intSet.contains(1025));
}