@Test
 public void testGetForMoreElements() throws Exception {
   BitSetObjectMap<String> map =
       new BitSetObjectMap<String>(DEFAULT_VALUE).add(bs(1), "43").add(bs(2, 3, 4), "44");
   assertThat(map.get(bs(1)), equalTo("43"));
   assertThat(map.get(bs(2, 3, 4)), equalTo("44"));
   assertThat(map.get(bs(0, 8, 15)), equalTo("42"));
 }
 @Test
 public void testGetForEmptyMap() throws Exception {
   BitSetObjectMap<String> map = new BitSetObjectMap<String>(DEFAULT_VALUE);
   assertThat(map.get(bs()), equalTo("42"));
   assertThat(map.get(bs(0, 8, 15)), equalTo("42"));
 }
 @Test
 public void testKeys() throws Exception {
   BitSetObjectMap<String> map = new BitSetObjectMap<String>(DEFAULT_VALUE).add(bs(1), "55");
   assertThat(map.keys(), arrayContaining(bs(1)));
 }
 @Test
 public void testGetDefaultValue() throws Exception {
   BitSetObjectMap<String> map = new BitSetObjectMap<String>(DEFAULT_VALUE);
   assertThat(map.getDefaultValue(), equalTo("42"));
 }
 @Test
 public void testKeysEmpty() throws Exception {
   BitSetObjectMap<String> map = new BitSetObjectMap<String>(DEFAULT_VALUE);
   assertThat(map.keys().length, equalTo(0));
 }