Unmarshalling empty tag into new instances

I am trying to unmarshall something like below into their JAXB equivalents, and the fields are as expected being populated with nulls

XML

<University>
   <StudentFirstNames/>
</University>

JAXB Pojo

public class University {
  List<StudentFirstNames> studentFirstNames = null;

  public void getStudentFirstNames() {
    return studentFirstNames 
   }

  public void setStudentFirstNames() {
   this.studentFirsNames = studentFirstNames;
  }
}

After unmarshalling I am returned back null when I lookup the member in the JAXB object

 university.getStudentFirstNames() --> null

In this specific situation I am trying to resolve, I need to replace empty tags with new instance of that particular type. For example in the above, I am expecting back a new ArrayList () instead of null. I know this sounds counter intuitive but that is what I have to do for satisying code downstream.

Is there a global fix to resolve such instances. Thanks in advance.