### Question:
ResourceChangeInfo { public boolean isCheckRequiredForGroup(final String groupName) { notNull(groupName); return currentHash == null; }  void updateHashForGroup(final String hash, final String groupName); void reset(); boolean isChanged(final String groupName); boolean isCheckRequiredForGroup(final String groupName); @Override String toString();  }### Answer:
@Test(expected = NullPointerException.class) public void cannotIfCheckRequiredForNullGroup() { victim.isCheckRequiredForGroup(null); }
@Test public void shouldRequireChangeByDefault() { assertTrue(victim.isCheckRequiredForGroup(GROUP1_NAME)); }