Hi ���զ�,
Why don't you simply use the ODMG DMap Implementation?
This will save you a lot of work!
Thomas
���զ� wrote:
> Hi!
> I try to use user-defined collections to implement 1:n associations. I have read
> tutorial3.html, and
> code a sample program almost like as ArticleCollection class. Its name
> MapCollection1.class :
> <--------------------------------------------------------------------------------------->
> package businessclass;
>
> import org.apache.ojb.broker.ManageableCollection;
> import java.util.*;
>
> public class MapCollection1 extends HashMap implements ManageableCollection,
> {
>
> public void add(SimpleUserForMap pMember)
> {
> this.put(pMember.getOID(),pMember);
> }
>
> /**
> * add a single Object to the Collection. This method is
> * used during reading Collection elements from the
> * database. Thus it is is save to cast anObject
> * to the underlying element type of the collection.
> */
> public void ojbAdd(java.lang.Object anObject)
> {
> if (anObject instanceof SimpleUserForMap){
> add((SimpleUserForMap) anObject);
> }
> }
>
> /**
> * adds a Collection to this collection. Used in reading
> * Extents from the Database.
> * Thus it is save to cast otherCollection to this.getClass().
> */
> public void ojbAddAll(
> ManageableCollection otherCollection)
> {
> this.putAll(
> ((MapCollection1) otherCollection);
> }
>
> /**
> * returns an Iterator over all elements in the collection.
> * Used during store and delete Operations.
> */
> public java.util.Iterator ojbIterator()
> {
> return this.values().iterator();
> }
> }
> <--------------------------------------------------------------------------------------->
>
> Then I declare two objects SimpleUserForMap and SimpleOrgForMap.
> SimpleOrgForMap has a MapCollection1 type property named "users" .Its elements are
> SimpleUserForMap object.
> They are:
>
> <--------------------------------------------------------------------------------------->
> package businessclass;
>
> import persistentlayertest.PersistentObject;
>
> public class SimpleUserForMap extends PersistentObject{
> /** name*/
> private String name = null;
>
> public String getName() {
> return this.name;
> }
>
> public void setName(String pNewValue) {
> this.name = pNewValue;
> }
>
> private String organizationOID = "";
>
> public String getOrganizationOID(){
> return this.organizationOID;
> }
> public void setOrganizationOID(String pNewValue){
>
> this.organizationOID = pNewValue;
> }
>
> private SimpleOrgForMap organization = null;
>
> public SimpleOrgForMap getOrganization(){
> return this.organization;
> }
>
> public void setOrganization(SimpleOrgForMap pNewValue){
> this.organization = pNewValue;
> setOrganizationOID(pNewValue.getOID());
> }
>
> public SimpleUserForMap() {
> }
> }
> <--------------------------------------------------------------------------------------->
> package businessclass;
>
> import persistentlayertest.PersistentObject;
> import java.util.Collection;
> import java.util.Vector;
> import java.util.Map;
> import java.util.HashMap;
> import org.odmg.DMap;
> import org.apache.ojb.odmg.collections.DMapImpl;
>
> public class SimpleOrgForMap extends PersistentObject{
> private MapCollection1 users ;
>
> public void addUsers(SimpleUserForMap pUser){
> System.out.println("***************Add Users For MapCollection.");
> if (users == null)
> {
> users = new MapCollection1();
> }
> this.users.add(pUser);
> }
> public MapCollection1 getUsers(){
> System.out.println("***************Get Users For MapCollection.");
> return this.users;
> }
>
> public void setUsers(MapCollection1 pMembers){
> this.users = pMembers;
> }
> public SimpleOrgForMap() {
> }
> }
> <--------------------------------------------------------------------------------------->
>
> The repository is:
> <--------------------------------------------------------------------------------------->
>
> <class-descriptor class="businessclass.SimpleOrgForMap" table="SimpleOrg">
> <field-descriptor id="1"
> name="OID"
> column="OID"
> jdbc-type="CHAR"
> primarykey="true"
> />
>
> <collection-descriptor
> name="users"
> element-class-ref="businessclass.SimpleUserForMap"
> collection-class="businessclass.MapCollection1"
> >
> <inverse-foreignkey field-id-ref="3"/>
> </collection-descriptor>
> </class-descriptor>
>
> <class-descriptor class="businessclass.SimpleUserForMap" table="SimpleUser">
> <field-descriptor id="1"
> name="OID"
> column="OID"
> jdbc-type="CHAR"
> primarykey="true"
> />
> <field-descriptor id="2"
> name="name"
> column="name"
> jdbc-type="VARCHAR"
> />
> <field-descriptor id="3"
> name="organizationOID"
> column="organizationOID"
> jdbc-type="CHAR"
> />
> <reference-descriptor
> name="organization"
> class-ref="businessclass.SimpleOrgForMap"
> >
> <foreignkey field-id-ref="3"/>
> </reference-descriptor>
> </class-descriptor>
>
> <--------------------------------------------------------------------------------->
>
> I new a SimpleOrgForMap object that there are several SimpleUserForMap elements in
> its users property.
> When I presistent SimpleOrgForMap , always raise the error message:
>
> 11:40:27,125 INFO [STDOUT] Locking obj [EMAIL PROTECTED] with lock mode 4 failed
> 11:40:27,140 INFO [STDOUT] businessclass.MapCollection1
> 11:40:27,156 ERROR [STDERR] org.odmg.ClassNotPersistenceCapableException:
> businessclass.MapCollection1
> 11:40:27,171 ERROR [STDERR] at org.apache.ojb.odmg.ObjectEnvelope.manage(Unknown
> Source)
> 11:40:27,187 ERROR [STDERR] at org.apache.ojb.odmg.ObjectEnvelope.<init>(Unknown
> Source)
> 11:40:27,203 ERROR [STDERR] at
> org.apache.ojb.odmg.TransactionImpl.register(Unknown Source)
> 11:40:27,218 ERROR [STDERR] at org.apache.ojb.odmg.TransactionImpl.lock(Unknown
> Source)
> 11:40:27,234 ERROR [STDERR] at
> org.apache.ojb.odmg.NarrowTransaction.lock(Unknown Source)
> :
> :
> What wrong with my code or repository setting? May I set OJB.properties some
> attribute specially??
>
> Thanks in advance
> Dogie Tsai
>
> ps.I use odmg to persistent objects, and use it with JBoss3.0.4.
> The 1:n associations can work well with Collection,List and Vector.
>
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
