Failed hibernate mapping: An association from the table X refers to an unmapped class Y

Question

Hi I'm trying to map this pojo Rent class to create his hibernate mapping file .

Rent.java (POJO):

  public class Rent implements Serializable {

     private static final long serialVersionUID = 1L;

       Employee employee;
       Client client;
       Car car;

    /* + getter and setter... */
  } 

My intention is to create web-application where the user can set which employee have rented a car to a client.So this is the implementation i've tried

Rent.hbm.xml :

<hibernate-mapping>
  <class name="com.google.musicstore.domain.Rent" table="RENT">
    <id name="id" column="RENT_ID">
       <generator class="native"/>
    </id>
    <one-to-one name="car"  class="com.project.domain.Car"
       cascade="save-update">
    </one-to-one>
    <one-to-one name="client"  class="com.project.domain.Client"
       cascade="save-update">
    </one-to-one>
    <many-to-one name="employee"  class="com.project.domain.Employee"
       cascade="save-update">
    </many-to-one>
  </class>
</hibernate-mapping>

But it gives me this error:

   [java] Initial SessionFactory creation failed.org.hibernate.MappingException: An association from the table RENT refers to an unmapped class: com.project.domain.Employee

What am i doing wrong? Thank you for the help.

I've also mapped all the entities in the hibernate.cfg.xml:

    <mapping resource="com/project/carRentalAgency/domain/Employee.hbm.xml"/>
    <mapping resource="com/project/carRentalAgency/domain/Client.hbm.xml"/>
    <mapping resource="com/project/carRentalAgency/domain/Car.hbm.xml"/>
    <mapping resource="com/project/carRentalAgency/domain/Rent.hbm.xml"/>

[EDIT] As request i've added the files Employee.hbm.xml

   <hibernate-mapping>
       <class name="com.project.carRentalAgency.domain.Employee" table="EMPLOYEE">
            <id name="id" type="long" access="field">
                <column name="ID" />
                <generator class="increment" />
            </id>
            <property name="name" type="java.lang.String" access="field">
                <column name="EMPLOYEE_NAME" />
           </property>
           <property name="surname" type="java.lang.String">
                <column name="EMPLOYEE_SURNAME" />
           </property>
           <property name="username" type="java.lang.String">
                <column name="EMPLOYEE_USERNAME" />
           </property>
           <property name="password" type="java.lang.String">
                <column name="EMPLOYEE_PASSWORD" />
           </property>

      </class>
   </hibernate-mapping>

Answer 1

I've found that usually this error occurred because the Build Action for the hibernate file classname.hbm.xml properties is not set to Embedded Resource.