<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
      "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
      "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory name="sessionFactory">
        <property name="hibernate.connection.driver_class">org.postgresql.Driver</property>
        <property name="hibernate.connection.password">postgres</property>
        <property name="hibernate.connection.url">...</property>
        <property name="hibernate.connection.username">...</property>
        <property name="hibernate.dialect">org.hibernate.dialect.PostgreSQLDialect</property>
        <mapping class="net.marioosh.wicket.start1.model.User"/>
        ...
        <mapping class="net.marioosh.wicket.start1.model.Group"/>
    </session-factory>
</hibernate-configuration>

@Entity
@Table(name="tuser")
public class User implements Serializable{
   private int idUser;
   private String login;
   private String pass;

   public int getIdUser() {
      return idUser;
   }
   
   @Id
   public void setIdUser(int idUser) {
      this.idUser = idUser;
   }
            ...
}