Writing JUnit tests for Spring Validator implementation

Question

I\'m using Spring Validator implementations to validate my object and I would like to know how do you write a unit test for a validator like this one:

public         


        

Answer 1

It is a really straight forward test without any mock. (just the error-object creation is a bit tricky)

@Test
public void testValidationWithValidAddress() {
    AdressValidator addressValidator = new AddressValidator();
    CustomValidator validatorUnderTest = new CustomValidator(adressValidator);

    Address validAddress = new Address();
    validAddress.set... everything to make it valid

    Errors errors = new BeanPropertyBindingResult(validAddress, "validAddress");
    validatorUnderTest.validate(validAddress, errors);

    assertFalse(errors.hasErrors()); 
}


@Test
public void testValidationWithEmptyFirstNameAddress() {
    AdressValidator addressValidator = new AddressValidator();
    CustomValidator validatorUnderTest = new CustomValidator(adressValidator);

    Address validAddress = new Address();
    invalidAddress.setFirstName("")
    invalidAddress.set... everything to make it valid exept the first name

    Errors errors = new BeanPropertyBindingResult(invalidAddress, "invalidAddress");
    validatorUnderTest.validate(invalidAddress, errors);

    assertTrue(errors.hasErrors());
    assertNotNull(errors.getFieldError("firstName"));
}

BTW: if you really want to make it more complicate and make it complicate by a mock, then have a look at this Blog, they use a two mocks, one for the object to test (ok, this is useful if you can not create one), and a second for the Error object (I think this is more complicated the it must be.)