XML databinding question

Can anybody suggest possible databinding options which would bind(map)
xml instance docs(which conforms to some pre-defined xsd) to a
PRE-EXISTING java object (see below example). I looked at xstream which
seems to be a good option for serializing/deserializing objects to xml
and vice-versa(xstream does not care for schemas). Same with JAXB,
Castor or Xmlbeans ..I have not found a way to map the below xml to my
custom java obj?

Any pointers will be very helpful.

TIA,
Guru.

an e.g. would be :
<schema>
  <complexType>
    <sequence>
      <element name="name" type="string" />
      <element name="deptid" type="int" />
    </sequence>
  </complexType>
</schema>

Instance doc:
<employee>
    <name>Joe Trader</name>
    <deptid>10</deptid>
</employee>

Custom Java obj (with no default const., accessors or mutators):
public class Employee
{
  public final String name;
  public final int deptid;

  public Employee (String name, int deptid) // overloaded const.
  {
    this.name = name;
    this.deptid = deptid;
  }

}