private void addTeachers(List teachers, List<IEmployee> employees) {
private void addTeachers(List<ITeacher> teachers, List<IEmployee> employees) {
    private void addTeachers(List teachers, List<IEmployee> employees) {        for (IEmployee employee : employees) {            ITeacher teacher = employee.getPerson().getTeacher();            if (teacher != null)                teachers.add(teacher);        }    }