<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping SYSTEM "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
<hibernate-mapping>
  <class name="dvs.summit.data.items.BaseItem" table="Item" discriminator-value="base">
    <id name="id" type="long" column="id" unsaved-value="null">
      <generator class="hilo"/>
    </id>
    <discriminator column="type"/>
    <many-to-one name="device" column="device_id" class="dvs.summit.devices.DeviceData"/>
    <property name="itemIndex" column="itemIndex" type="integer"/>
   
    <!-- Item subclass -->
    <subclass name="dvs.summit.data.items.Item" discriminator-value="item">
      <property name="arrayIndex" column="arrayIndex" type="integer"/>
      <property name="valueId"  column="value_id"/>
      <many-to-one name="owningArray" column="arrayItem_id"/>
      <subclass name="dvs.summit.data.items.StringItem" discriminator-value="string"/>
      <subclass name="dvs.summit.data.items.BCDItem" discriminator-value="bcd"/>
      <subclass name="dvs.summit.data.items.IntegerItem" discriminator-value="integer">
        <subclass name="dvs.summit.data.items.S8Item" discriminator-value="S8"/>
        <subclass name="dvs.summit.data.items.S16Item" discriminator-value="S16"/>
        <subclass name="dvs.summit.data.items.S32Item" discriminator-value="S32"/>
        <subclass name="dvs.summit.data.items.S64Item" discriminator-value="S64"/>
        <subclass name="dvs.summit.data.items.U8Item" discriminator-value="U8"/>
        <subclass name="dvs.summit.data.items.U16Item" discriminator-value="U16"/>
        <subclass name="dvs.summit.data.items.U32Item" discriminator-value="U32"/>
      </subclass>
      <subclass name="dvs.summit.data.items.FloatItem" discriminator-value="float">
        <subclass name="dvs.summit.data.items.F32Item" discriminator-value="F32"/>
        <subclass name="dvs.summit.data.items.F64Item" discriminator-value="F64"/>
        <subclass name="dvs.summit.data.items.FloatDecItem" discriminator-value="FD64"/>
      </subclass>
      <subclass name="dvs.summit.data.items.DateItem" discriminator-value="date">
        <subclass name="dvs.summit.data.items.D32Item" discriminator-value="D32"/>
        <subclass name="dvs.summit.data.items.D64Item" discriminator-value="D64"/>
      </subclass>
      <subclass name="dvs.summit.data.items.ByteArrayItem" discriminator-value="binary"/>
      <subclass name="dvs.summit.data.items.AlarmItem" discriminator-value="alarm"/>
    </subclass>
   
    <!-- Array subclass -->
    <subclass name="dvs.summit.data.items.ArrayItem" discriminator-value="array">
      <list name="items" inverse="true" cascade="all">
        <key column="arrayItem_id"/>
        <index column="arrayIndex"/>
        <one-to-many class="dvs.summit.data.items.Item"/>
      </list>
      <subclass name="dvs.summit.data.items.StringArrayItem" discriminator-value="string-array"/>
      <subclass name="dvs.summit.data.items.AlarmArrayItem" discriminator-value="alarm-array"/>
    </subclass>
  </class>
</hibernate-mapping>

id    type    device_id    itemIndex    arrayIndex    arrayItem_id
-----------------------------------------------------------------------------
100    array    5            7         null          null
101    S8      null        null        0              100
101    S8      null        null        1              100
101    S8      null        null        2              100

id    type    device_id    itemIndex    arrayIndex    arrayItem_id
-----------------------------------------------------------------------------
100    array   5            7            null          null
101    S8      5            7            0              100
101    S8      5            7            1              100
101    S8      5            7            2              100