EJB / EE :: Bean Annotations And Unit Testing?

I have a bean that represents data been collected from a form on a jsp page. Currently I would like to validate my fields and write some test cases for them. As you can see from my test case example I test a string in the hope that it fails because it contains only one letter. My problem is my unit test is passing. The reason this is from what I can tell is that at runtime it fails when I try to persist my object using my entity manager. During my unit test I just I don’t call my entity manager I just try and set the field.

What I thought would happen was that when I use my bean fields set method the annotations would be checked and fail at that point. Hence why I expected my unit test in this case to fail.

What I would like to know is

1.Are annotations specifically designed to validate when I persist my object and am I using them incorrectly at this point?

2.Is this the best method to use to validate fields, is there a better way, should I write my own code to validate for me when I set my value?

a. Should I throw an exception from the set method of each bean field?

Unit Test:

@Test
public void testName(){
Human h=new Human();
try {
h.setFname("a");
} catch (Exception e) {
// TODO Auto-generated catch block
fail("failed");
e.printStackTrace();

[code]....