Hi Riccardo,
You may also try to use the `isSourceIndependentFromTargetChange()` method
instead of `isToMany()` in your template. It should cover your case and fix
the problem.
On Wed, Jan 10, 2024 at 10:10 AM Riccardo De Menna <deme...@tuorlo.net>
wrote:
> Hi Michael,
>
> Thank you for helping. Yes… you modeled exactly what I described down to
> the delete rules. I imported your files in modeler and run class generation
> but I still get the relationship (TO_SHIP in your model) to appear as
> mandatory. Could it be an issue in class generation?
>
> This is a little VE snippet I use in my template to output a static list
> of mandatory relationships.
>
> #foreach( $rel in ${object.DeclaredRelationships} )
> #if (${rel.isMandatory()} && !${rel.ToMany} )
> #set($bar =
> $requiredRelationships.add("${stringUtils.capitalizedAsConstant($rel.Name)}_PROPERTY"))
> #end
> #end
> public static final List<String> REQUIRED_RELATIONSHIPS = List.of(
> #foreach( $rel in ${requiredRelationships} )
> ${rel}#if(!$foreach.last),#end
> #end
> );
>
> And contrary to what I would expect, I get this in my superclass:
>
> public static final List<String> REQUIRED_RELATIONSHIPS = List.of(
> TO_SHIP_PROPERTY
> );
>
> Riccardo De Menna
>
>
> > On 10 Jan 2024, at 01:20, Michael Gentry <blackn...@gmail.com> wrote:
> >
> > Hi Riccardo,
> >
> > I may have completely misunderstood your intention, but here is my first
> > cut for a model:
> >
> > cayenne-o2o.xml:
> > <?xml version="1.0" encoding="utf-8"?>
> > <domain xmlns="http://cayenne.apache.org/schema/10/domain";
> > xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
> > xsi:schemaLocation="http://cayenne.apache.org/schema/10/domain
> > https://cayenne.apache.org/schema/10/domain.xsd";
> > project-version="10">
> > <map name="datamap"/>
> > </domain>
> >
> > datamap.map.xml:
> > <?xml version="1.0" encoding="utf-8"?>
> > <data-map xmlns="http://cayenne.apache.org/schema/10/modelMap";
> > xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
> > xsi:schemaLocation="http://cayenne.apache.org/schema/10/modelMap
> > https://cayenne.apache.org/schema/10/modelMap.xsd";
> > project-version="10">
> > <property name="defaultLockType" value="1"/>
> > <property name="defaultPackage" value="org.test"/>
> > <db-entity name="SHIPMENT">
> > <db-attribute name="ID" type="BIGINT" isPrimaryKey="true"
> isMandatory="true"
> > />
> > </db-entity>
> > <db-entity name="SHIPMENT_NUMBER">
> > <db-attribute name="ID" type="BIGINT" isPrimaryKey="true"
> isMandatory="true"
> >>
> > <info:property xmlns:info="http://cayenne.apache.org/schema/10/info";
> name=
> > "comment" value="This ID is the same as SHIPMENT's ID."/>
> > </db-attribute>
> > <db-attribute name="NUM" type="INTEGER">
> > <info:property xmlns:info="http://cayenne.apache.org/schema/10/info";
> name=
> > "comment" value="This is the shipment number."/>
> > </db-attribute>
> > </db-entity>
> > <obj-entity name="Shipment" className="org.test.Shipment" lock-type=
> > "optimistic" dbEntityName="SHIPMENT"/>
> > <obj-entity name="ShipmentNumber" className="org.test.ShipmentNumber"
> > lock-type="optimistic" dbEntityName="SHIPMENT_NUMBER">
> > <obj-attribute name="num" type="java.lang.Integer"
> db-attribute-path="NUM"/>
> > </obj-entity>
> > <db-relationship name="toShipNum" source="SHIPMENT"
> target="SHIPMENT_NUMBER"
> >>
> > <db-attribute-pair source="ID" target="ID"/>
> > </db-relationship>
> > <db-relationship name="toShip" source="SHIPMENT_NUMBER" target="SHIPMENT"
> > toDependentPK="true">
> > <db-attribute-pair source="ID" target="ID"/>
> > </db-relationship>
> > <obj-relationship name="toShipNum" source="Shipment"
> target="ShipmentNumber"
> > deleteRule="Cascade" db-relationship-path="toShipNum"/>
> > <obj-relationship name="toShip" source="ShipmentNumber" target="Shipment"
> > deleteRule="Deny" db-relationship-path="toShip"/>
> > </data-map>
> >
> > Copy/Paste these files somewhere, then try loading them up into your 4.2
> > Modeler and see if it is close.
> >
> > mrg
> >
> >
> > On Tue, Jan 9, 2024 at 9:54 AM Riccardo De Menna <deme...@tuorlo.net>
> wrote:
> >
> >> Hi,
> >>
> >> Can someone help me understand something?
> >>
> >> I’m trying to model a one-to-one relationship between two entities but I
> >> can’t seem to get the relationship to be optional.
> >>
> >> In my specific case I need to model an entity representing shipments
> with
> >> a postal service. Each shipment needs to have a number taken from a
> >> range/group that is pre-assigned by the postal service.
> >>
> >> Thus I created a SHIPMENT_NUMBER entity with just an INTEGER attribute
> and
> >> then used that attribute to build the relationship with the SHIPMENT
> >> entity. Possibly with “To dep PK” as well.
> >>
> >> I want the relationship to be optional so that I can generate
> >> SHIPMENT_NUMBER as many as I want and populate them with the numbers
> >> assigned by the postal service and only later, when the real SHIPMENT is
> >> actually needed/created, link it with the number in a one-to-one
> fashion.
> >>
> >> I’m not sure why, but my class generated content always shows the
> >> relationship as mandatory.
> >>
> >> Coming from the WebObjects world, I'm used to a modeler that explicitly
> >> shows checkboxes for isMandatory on relationships like with the
> attributes.
> >> Here in Cayenne it seems that optionality is implicitly determined
> based on
> >> the design.
> >>
> >> Have I misunderstood something? Is my design flawed?
> >>
> >> Any tip is appreciated.
> >>
> >> Regards,
> >> Riccardo
>
>
--
Best regards,
Nikita Timofeev
