Hibernate: mapping with a map and getting argument type mismatch

Question

I've got this class DepartmentPerson in Java where I've mapped a Map in Hibernate as following:

<map cascade="save-update" name="acceptByPeriod" table="tbl_department_people_accept">
        <key column="fk_department_people_asc_id"/>
        <map-key column="fk_period_id" type="int"/>
        <element type="int" column="fld_accept"/>
    </map>

and in the class I have acceptByPeriod defined as following:

private Map<Integer, Integer> acceptByPeriod = new HashMap<>();

Whenever I run a query on DepartmentPerson, I get the message: "java.lang.IllegalArgumentException: argument type mismatch". This has something to do with the acceptByPeriod mapping, as when I remove it the problem disappears. All 3 fields on array tbl_department_people_accept are of type int. I really can't understand what is going wrong; I've done this type of mapping before in different classes (with a <Integer, Date> map and an <Integer,DepartmentEEK> map, DepartmentEEK being a composite-element) and it worked just fine; in fact I've copied the code from one of those classes and just changed the names of the fields. I am at my wits' end here. Any idea how to get it to work, or at least how to get to the bottom of which field is giving an argument type mismatch?

Answer 1

Found the problem with the help of this post: IllegalArgumentException: argument type mismatch in Hibernate

The problem wasn't in the types of the map, it was in its setter. I had written it as:

public void setAcceptByPeriod(HashMap<Integer, Integer> acceptByPeriod)

when it needed to be

public void setAcceptByPeriod(Map<Integer, Integer> acceptByPeriod)