On 12 April 2013 10:06, 张峰昌 <[email protected]> wrote:
> Hi Dan:
> I have update the isis-objectstore-jdo from 1.0.0 to 1.0.1-SNAPSHOT,and the
> DataNucleusObjectStore.loadPojo works fine.
> There are two reasons to use "Application style Identity" for me:.
> (1)、Domain Root Entity should have their Identity, and we should model the
> relationship between the Root Entities with refrence to Root Entity's
> Identity insteadof to Root Entity Object directly.
> References:
> Effective Aggregate Design:Part II Making Aggregate work togather
> Author:Vaughn Vernon
> https://vaughnvernon.co/?p=139
Sorry, I don't agree.
This is a style of doing DDD that (in my opinion) over-emphasises the role
of root aggregates, and underemphasises the role of such things as patterns
such as the module.
I also detect an emphasis on aggregates with the current hype around NoSQL
databases. When an aggregate = a JSON doc in MongoDB, then, yes, sure,
links between aggregates must be done using Ids.
But if using a mature ORM such as JDO (one that supports polymorphic
relationships through interfaces), there's no reason to do this.
>
> (2)、Domain Root Entity Identity should not depends on
> JDOHelper.getObjectId(obj).
>
>
How does it? Especially if you use datastore-defined identity, eg as in
the ToDoItem example:
@javax.jdo.annotations.PersistenceCapable(identityType=IdentityType.DATASTORE)
@javax.jdo.annotations.DatastoreIdentity(strategy=javax.jdo.annotations.IdGeneratorStrategy.IDENTITY)
public class ToDoItem { .. }
Cheers
Dan
> Best Regards
>
> Alain
>
> -----邮件原件-----
> 发件人: Dan Haywood [mailto:[email protected]]
> 发送时间: 2013年4月11日 15:16
> 收件人: dev
> 主题: Re: DataNucleusObjectStore.loadPojo problem
>
> Hi Alain
> I suspect your JDO annotations are wrong, but before I go off on a wrong
> tangent, let me ask: what is your intent for the id? should it be assigned
> by the DBMS/JDO, or should it be assigned by the application?
> Dan
>
>
> On 11 April 2013 03:26, 张峰昌 <[email protected]> wrote:
>
> > Hi,Dan:
> >
> >
> >
> > It seems that there are problem when to recreate an pojo with
> > DataNucleusObjectStore.loadPojo. The entity I have defined that use
> > entity itself ID which type is java.lang.Long.It’s work fine when
> > persist the entity,but will failed when load it to display in UI.
> >
> > The failed reason is DataNucleusObjectStore.loadPojo passed an
> > javax.jdo.identity.LongIdentity typed value into
> > org.datanucleus.api.jdo.JDOPersistenceManager.getObjectById,but
> > datanucleus requires Long typed value.
> >
> >
> >
> >
> >
> > Exception statack :
> >
> > javax.jdo.JDOFatalInternalException: The key value passed to construct
> > a SingleFieldIdentity of type "javax.jdo.identity.LongIdentity" for
> > class "com.thingray.party.dom.person.Person" is of an incorrect type
> > ("javax.jdo.identity.LongIdentity") - should be "Long".
> >
> > at
> >
> > org.datanucleus.api.jdo.NucleusJDOHelper.getJDOExceptionForNucleusExce
> > ption(
> > NucleusJDOHelper.java:561)
> >
> > at
> >
> > org.datanucleus.api.jdo.JDOPersistenceManager.newObjectIdInstance(JDOP
> > ersist
> > enceManager.java:1622)
> >
> > at
> >
> > org.datanucleus.api.jdo.JDOPersistenceManager.getObjectById(JDOPersist
> > enceMa
> > nager.java:1740)
> >
> > at
> >
> > org.apache.isis.objectstore.jdo.datanucleus.DataNucleusObjectStore.loa
> > dPojo(
> > DataNucleusObjectStore.java:390)
> >
> > at
> >
> > org.apache.isis.objectstore.jdo.datanucleus.persistence.adaptermanager
> > .DataN
> > ucleusPojoRecreator.recreatePojo(DataNucleusPojoRecreator.java:38)
> >
> > at
> >
> > org.apache.isis.core.runtime.persistence.adaptermanager.AdapterManager
> > Defaul
> > t.adapterFor(AdapterManagerDefault.java:300)
> >
> > at
> >
> > org.apache.isis.viewer.wicket.model.mementos.ObjectAdapterMemento$Type
> > $2.rec
> > reateAdapter(ObjectAdapterMemento.java:104)
> >
> > at
> >
> > org.apache.isis.viewer.wicket.model.mementos.ObjectAdapterMemento$Type
> > .getAd
> > apter(ObjectAdapterMemento.java:170)
> >
> > at
> >
> > org.apache.isis.viewer.wicket.model.mementos.ObjectAdapterMemento.getO
> > bjectA
> > dapter(ObjectAdapterMemento.java:288)
> >
> > at
> >
> > org.apache.isis.viewer.wicket.model.models.EntityModel.load(EntityMode
> > l.java
> > :193)
> >
> >
> >
> > The entity I have defined:
> >
> >
> >
> >
> >
> > import java.util.ArrayList;
> >
> > import java.util.List;
> >
> >
> >
> > import javax.jdo.annotations.IdGeneratorStrategy;
> >
> > import javax.jdo.annotations.IdentityType;
> >
> > import javax.jdo.annotations.Inheritance;
> >
> > import javax.jdo.annotations.InheritanceStrategy;
> >
> > import javax.jdo.annotations.PersistenceCapable;
> >
> > import javax.jdo.annotations.Persistent;
> >
> > import javax.jdo.annotations.PrimaryKey;
> >
> > import javax.jdo.annotations.Queries;
> >
> > import javax.jdo.annotations.Query;
> >
> > import javax.jdo.annotations.Version;
> >
> > import javax.jdo.annotations.VersionStrategy;
> >
> >
> >
> > import org.apache.isis.applib.annotation.Hidden;
> >
> > import org.apache.isis.applib.annotation.MemberOrder;
> >
> > import org.apache.isis.applib.annotation.Named;
> >
> > import org.apache.isis.applib.annotation.Optional;
> >
> > import org.apache.isis.applib.annotation.Title;
> >
> > import org.apache.isis.applib.annotation.When;
> >
> > import org.apache.isis.applib.value.Date;
> >
> >
> >
> > import com.thingray.party.dom.Party;
> >
> > import com.thingray.party.dom.person.value.GenderType;
> >
> > import com.thingray.party.dom.role.value.PartyRoleType;
> >
> > /**
> >
> > *
> >
> > * 人。
> >
> > * @author alain
> >
> > * @version $Revision 1.0$ 2012-10-15
> >
> > * @since 1.0
> >
> > * @author (lastest modification by $Author$)
> >
> > */
> >
> > @PersistenceCapable(table="PA_PERSON")
> >
> > @Queries({
> >
> > @Query(name = "person_find_by_name",
> >
> > value = " SELECT FROM
> > com.thingray.party.dom.person.Person " +
> >
> > " WHERE
> > firstName.indexOf(:personName)>=0 " +
> >
> > " ORDER BY
> > firstName"),
> >
> > @Query(name = "person_find_by_login_account",
> >
> > value = " SELECT FROM
> > com.thingray.party.dom.person.Person " +
> >
> > " WHERE
> > loginAccount==:loginAccount")
> >
> > })
> >
> > @Inheritance(strategy=InheritanceStrategy.NEW_TABLE)
> >
> > @Version(strategy=VersionStrategy.VERSION_NUMBER,column="VERSION")
> >
> > public class Person {
> >
> > // {{ PartyID (参与方标识)
> >
> >
> >
> > private Long partyID;
> >
> >
> >
> > @MemberOrder(sequence = "1")
> >
> > @Hidden(when=When.UNTIL_PERSISTED)
> >
> > @Named("参与方标识")
> >
> > @Persistent(primaryKey = "true", valueStrategy =
> > IdGeneratorStrategy.NATIVE)
> >
> > public Long getPartyID() {
> >
> > return partyID;
> >
> > }
> >
> >
> >
> > public void setPartyID(final Long partyID) {
> >
> > this.partyID = partyID;
> >
> > }
> >
> >
> >
> > // }}
> >
> >
> >
> > // {{ LastName (姓)
> >
> > private String lastName;
> >
> >
> >
> > @MemberOrder(sequence = "1")
> >
> > @Named("姓")
> >
> > @Title(sequence="1")
> >
> > public String getLastName() {
> >
> > return lastName;
> >
> > }
> >
> >
> >
> > public void setLastName(final String lastName) {
> >
> > this.lastName = lastName;
> >
> > }
> >
> > // }}
> >
> >
> >
> > // {{ FirstName (名)
> >
> > private String firstName;
> >
> >
> >
> > @MemberOrder(sequence = "2")
> >
> > @Named("名")
> >
> > @Title(sequence="2")
> >
> > public String getFirstName() {
> >
> > return firstName;
> >
> > }
> >
> >
> >
> > public void setFirstName(final String firstName) {
> >
> > this.firstName = firstName;
> >
> > }
> >
> > // }}
> >
> > }
> >
> >
> >
> >
> >
> > Alain
> >
> >
> >
> >
> >
> >
>
>
