Bus.hbm.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
    <class name="com.andyshon.Bus" table="busses">
    <id column="bus_id" name="id" type="java.lang.Integer">
        <generator class="increment"/>
    </id>
<property column="number" name="number" type="java.lang.String"/>

<set name="drivers" table="busDriver" lazy="false">
<key column="bus_id"/>
<many-to-many column="driver_id" class="com.andyshon.Driver"/>
</set>

    </class>
</hibernate-mapping>