writing Junit tests for validator implementations

[degiere]

Hi, I'm looking for an example how to call a validator implementation (PersonValidator) outside of a web application context and form controller (AddPersonController). I'm trying to write a test class that would excersize this PersonValidator class and verify my rules work the way I intended them to. Given:

public class Person {
  private String name;
  private int age;

  // the usual suspects: getters and setters
}

and

public class PersonValidator implements Validator {
	
	public boolean supports(Class clzz) {
		return Person.class.equals(clzz);
	}
	
	public void validate(Object obj, Errors e) {
		ValidationUtils.rejectIfEmpty(e, "name", "name.empty");
		Person p = (Person)obj;
		if &#40;p.getAge&#40;&#41; < 0&#41; &#123;
			e.rejectValue&#40;"age", "negativevalue"&#41;;
		&#125; else if &#40;p.getAge&#40;&#41; > 110&#41; &#123;
			e.rejectValue&#40;"age", "tooold"&#41;;
		&#125;
	&#125;
&#125;

What might my PersonValidatorTest class look like?

[katentim]

Just typed this up without testing, but this should get you started:

    public void testNegativeAgeRejected() {
		Person person = new Person();
		person.setAge(-1);

		Errors errors = new BindException(person, "person");
		
		PersonValidator pv = new PersonValidator();
		pv.validate(person, errors);

		assertTrue(errors.hasFieldErrors("age"));
		assertEquals("negativevalue", errors.getFieldError("age").getCode());
    }

[leojhartiv]

To add to this, let me extend this question...

How do you unit test a Validator that delegates to another Validator?

For example, assuming Person had an Address object...

public class PersonValidator implements Validator {
	
	public boolean supports(Class clzz) {
		return Person.class.equals(clzz);
	}
	
	public void validate(Object obj, Errors e) {
		ValidationUtils.rejectIfEmpty(e, "name", "name.empty");
		Person p = (Person)obj;
		if (p.getAge() < 0) {
			e.rejectValue("age", "negativevalue");
		} else if (p.getAge() > 110) {
			e.rejectValue("age", "tooold");
		}
		
		e.pushNestedPath("address");
		ValidationUtils.invokeValidator( new AddressValidator(), obj.getAddress(), e);
		e.popNestedPath();
	}
}

How can I unit test PersonValidator, mocking AddressValidator's result, given that AddressValidator is instantiated within PersonValidator? The only thing I can think of is to make AddressValidator an injectable property, but I haven't seen people doing that in all of the Validator examples on this forum.

Thanks!
Leo