JavaでJSON-libAPIを使用して、型ヒントなしでBeanをXMLに変換するにはどうすればよいですか？

import net.sf.json.JSONObject;
import net.sf.json.xml.XMLSerializer;
public class ConvertBeanToXMLNoHintsTest {
   public static void main(String[] args) {
      Employee emp = new Employee("Krishna Vamsi", 115, 30, "Java");
      JSONObject jsonObj = JSONObject.fromObject(emp);
      System.out.println(jsonObj.toString(3)); //pretty print JSON
      XMLSerializer xmlSerializer = new XMLSerializer();
      xmlSerializer.setTypeHintsEnabled(false); // this method disable type hints
      String xml = xmlSerializer.write(jsonObj);
      System.out.println(xml);
   }
   public static class Employee {
      private String empName, empSkill;
      private int empId, age;
      public Employee(String empName, int empId, int age, String empSkill) {
         super();
         this.empName = empName;
         this.empId = empId;
         this.age = age;
         this.empSkill = empSkill;
      }
      public String getEmployeeName() {
         return empName;
      }
      public int getEmployeeId() {
         return empId;
      }
      public String getEmployeeSkill() {
         return empSkill;
      }
      public int getAge() {
         return age;
      }
   }
}

出力

{
   "employeeName": "Krishna Vamsi",
   "employeeSkill": "Java",
   "employeeId": 115,
   "age": 30
}
<?xml version="1.0" encoding="UTF-8"?>
<o>
   <age>30</age>
   <employeeId>115</employeeId>
   <employeeName>Krishna Vamsi</employeeName>
   <employeeSkill>Java</employeeSkill>
</o>