PreferenceScopeValidatorImpl implements PreferenceScopeValidator { protected boolean isEmpty(String str) { return str == null || str.trim().isEmpty(); } protected  PreferenceScopeValidatorImpl(); @Inject  PreferenceScopeValidatorImpl(@Customizable final PreferenceScopeTypes scopeTypes,
                                        @Customizable final PreferenceScopeResolutionStrategy scopeResolutionStrategy); @Override void validate(final PreferenceScope scope);  }
@Test public void isEmptyTest() { assertTrue(validator.isEmpty(null)); assertTrue(validator.isEmpty("")); assertTrue(validator.isEmpty(" ")); assertFalse(validator.isEmpty("anyString")); }