### Question:
AssertFalseValidator implements ConstraintValidator<AssertFalse, Boolean> { public boolean isValid(Boolean bool, ConstraintValidatorContext constraintValidatorContext) { if ( bool == null ) { return true; } return !bool; }  void initialize(AssertFalse constraintAnnotation); boolean isValid(Boolean bool, ConstraintValidatorContext constraintValidatorContext);  }### Answer:
@Test public void testIsValid() { assertTrue( constraint.isValid( null, null ) ); assertTrue( constraint.isValid( false, null ) ); assertTrue( constraint.isValid( Boolean.FALSE, null ) ); assertFalse( constraint.isValid( true, null ) ); assertFalse( constraint.isValid( Boolean.TRUE, null ) ); }