выборка из нескольких таблиц criteria hibernate

Вопрос, видимо, не сложный, но не могу понять сам принцип. У меня есть две таблицы со связью "один-ко-многим", но я не знаю как сделать выборку из них используя Criteria и поместить данные в DTO. SQL-запрос выглядит следующим образом:

SELECT DEPARTMENT.id, DEPARTMENT.name, empl.id, empl.name, empl.age
FROM EMPLOYEE AS empl
LEFT JOIN DEPARTMENT ON DEPARTMENT.id = empl.deapartment_id
WHERE empl.age = '15';

вот мои ентити:

@Entity
@Table(name = "DEPARTMENT")
public class Department implements Serializable {
@Id
@Column(name = "id", unique = true)
@GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
@Column(name = "name", unique = false, updatable = true, length = 45)
private String name;
@OneToMany(mappedBy = "departmentId", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
@OnDelete(action = OnDeleteAction.CASCADE)
private Set<Employee> employeesSet;
public Department() {
}
public Department(String name) {
    this.name = name;
}
public Department(int id, String name) {
    this.id = id;
    this.name = name;
}
public int getId() {
    return id;
}
public void setId(int id) {
    this.id = id;
}
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public Set<Employee> getEmployeesSet() {
    return employeesSet;
}
public void setEmployeesSet(Set<Employee> employeesSet) {
    this.employeesSet = employeesSet;
}
@Override
public String toString() {
    return "Department{" +
            "id=" + id +
            ", name=" + name + "}\n";
}
}

@Entity
@Table(name = "EMPLOYEE")
public class Employee implements Serializable {
@Id
@Column(name = "id")
@GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
@Column(name = "deapartment_id", updatable = true)
private int departmentId;
@Column(name = "age")
private String age;
@Column(name = "name", length = 25)
private String name;
public Employee() {
}
public Employee(String name,  String age, int departmentId) {
    this.setName(name);
    this.setAge(age);
    this.setDepartmentId(departmentId);
}
public Employee(int id, String name,  String age, int departmentId) {
    this.setId(id);
    this.setName(name);
    this.setAge(age);
    this.setDepartmentId(departmentId);
}
public int getId() {
    return id;
}
public void setId(int id) {
    this.id = id;
}
public String getAge() {
    return age;
}
public void setAge(String age) {
    this.age = age;
}
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public int getDepartmentId() {
    return departmentId;
}
public void setDepartmentId(int departmentId) {
    this.departmentId = departmentId;
}

@Override
public String toString() {
    return "Employee{" +
            " id=" + id +
            ", name=" + name +
            ", age=" + age +
            ", departmentId=" + departmentId +
" }\n";
 }
}

А вот мой DTO:

public class SomeDto2 {
private int departmentId;
private String depName;
private String age;
private String emplName;

public SomeDto2() {
}
public SomeDto2(int departmentId, String age, String emplName, String depName) {
    this.departmentId = departmentId;
    this.age = age;
    this.emplName = emplName;
    this.depName = depName;
}
public int getDepartmentId() {
    return departmentId;
}
public void setDepartmentId(int departmentId) {
    this.departmentId = departmentId;
}
public String getAge() {
    return age;
}
public void setAge(String age) {
    this.age = age;
}
public String getDepName() {
    return depName;
}
public void setDepName(String depName) {
    this.depName = depName;
}
public String getEmplName() {
    return emplName;
}
public void setEmplName(String emplName) {
    this.emplName = emplName;
}
@Override
public String toString() {
    return "SomeDto2{" +
            "departmentId=" + departmentId +
            ", age='" + age + '\'' +
            ", emplName='" + emplName + '\'' +
            ", depName='" + depName + '\'' +
            '}';
}
}

Пробовал сделать так:

List<SomeDto2> employees  = session.createCriteria(Department.class, "dep")
    .createAlias("dep.employeesSet", "empl")
    .add(Restrictions.eq("empl.age", "15"))
    .setResultTransformer(
            new AliasToBeanResultTransformer(SomeDto2.class)).list();

При этом получаю:

 java.lang.ClassCastException: ru.javastudy.hibernate.model.services.db.dto.SomeDto2 cannot be cast to java.util.Map 

Если кто-то знает хороший ресурс по хиберу с примерами кода (особенно по Сriteria), поделитесь пожалуйста, потому что с документации мне много чего пока не ясно.