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