Hybris - Data models

  Hybris data model 

Hybris Data Models are defined in the <extension>-items.xml file of each extension. 

Data model items(entities) are defined with itemtype elements.

Each item type is consist of a Java class and database Table.

items.xml  has six different tags and should be followed by same order 

automictypes 

collections

enumtypes

maptypes

relations

itemtypes

Atomic types: The item types which are primitive data types. 

For example, integer, float, double, boolean, Strings etc. They are defined in items.xml as follows.

<atomictype class=“java.lang.String” extends=“java.lang.Object” autocreate=“true” generate=“false”/>

Collection type: They are analogue of generic types in Java. A collection is a group of similiar type item types. Like a group of language used for a particular application could be stored as LanguageList.

<collectiontype code=”LanguageSet” elementtype=”Language” autocreate=”true” generate=”true” type=”set”/>

Enum types: The group of fixed constants are defined as enums, like any other language.

<enumtype code=“OrdStatus” autocreate=“true” generate=“true”>

<value code=“OPEN”/>

<value code=“IN-PROGRESS”/>

<value code=“CLOSE”/>

</enumtype>

Itemtypes: we need to define a new item type to specifies a specific ComposedType.

<itemtype code="OFFLineProduct" extends="Product"

                                  autocreate="true" generate="true"

                                  jaloclass="org.hm.core.jalo.OFFLineProduct">

                                  

<description>OFF Line product extension that contains additional attributes for off line.</description>

<deployment table="OFFLineProducts" typecode="10100" propertytable="ProductProps"/>

        <attributes>

                <attribute qualifier="store" type="java.lang.String">

                        <description> the products  store name </description>

                        <modifiers read="true" write="true" search="true" optional="false"/>

                        <persistence type="property" />

                </attribute>

                <attribute qualifier="intime" type="java.util.Date">

                        <description> the time stamp of the product  in </description>

                        <modifiers read="true" write="true" search="true" optional="false"/>

                        <persistence type="property" />

                </attribute>

                <attribute qualifier="outtime" type="java.util.Date">

                <description> the time stamp of the product  out </description>

                <modifiers read="true" write="true" search="true" optional="false"/>

                <persistence type="property" />

                </attribute>

        </attributes>

</itemtype>

Here we defined a new item type extending parent item or Generic item. 

GenericItem extends LocalizableItem extends ExtensibleItem extends Item

The jalo class, is the module class which creates the item. This class is auto generated. when you run ant build

Each of the characteristics of an item type is defined as attribute of item type. The attribute itself could be of any type.

autocreate - If 'true', the item will be created during initialization. Default is 'true'.

generate - If true, it generates constants for enum  and source code for item, it has no effect in automictypes,collections, maptype and relations.

attributes - Defines the list of item attributes.

read – If false, we cannot read this attribute, Defines if this attribute is readable or not.

write – If false,  we cannot write this attribute, Defines if this attribute is writable or not.

optional– if false, it is mandatory to initialize this attribute. Since it is not optional.

unique– if true, the attribute must hold a unique value. Similar to unique constraints in DBMS.

search – if true, the attribute is searchable through queries

persistence -

Defines how the values of the attribute will be stored. Possible values:  'property' (persistent), 'dynamic' (not persisted).

defaultvalue -Configures a default value for this attribute used if no value is provided. 

maptype: Like the java collection framework, a type, which defines map objects. 

<maptype code="localized:java.lang.String"

               argumenttype="Language"

               returntype="java.lang.String"

               autocreate="true"

               generate="false"/>

relationtype:

A RelationType defines a n-m or 1-n relation between types.

<relation code="OrderDiscountRelation" autocreate="true" generate="false" localized="false"

                deployment="de.hybris.platform.persistence.link.OrderDiscountRelation">

         <sourceElement qualifier="orders" type="AbstractOrder" cardinality="many" ordered="false">

            <modifiers read="true" write="true" search="true" optional="true"/>

         </sourceElement>

         <targetElement qualifier="discounts" type="Discount" cardinality="many" ordered="true" collectiontype="list">

            <modifiers read="true" write="true" search="true" optional="true"/>

         </targetElement>

      </relation>