Help: IllegalExpressionException vs. EJB 2.1 many-to-many relationship
Using Oracle WebLogic 11g (10.3.4). The appc tool is generating a warning regarding an illegal EJB QL expression for a many-to-may relationship in an EJB 2 Bean.
Details:
* Entity Bean "MSProduktKonfiguration"
* Entity Bean "MSAngebot"
* n-m relationship betwenn these two Entites, from MSProduktKonfiguration to MSAngebot by cmr field angebotLocal, from MSAngebot to MSProduktKonfiguration by cmr field produktKonfigurationenLocal
* Join table "MS_PRODUKT.ANGEBOT_POSITION"
Warnings from appc:
[java] Warning: [EJB:013094]The SELECT clause of this query contains an identifier 'bean.angebotLocal' that ends in a cmr-field. The EJB 2.1 specification section 11.2.7.1 requires that any related null objects belonging to the set corresponding to this cmr-field must be returned by this query however the database that will be used to execute this query does not sufficiently support SQL outer joins, therefore this query will not return any null objects that might otherwise be returned.
[java] Warning: [EJB:013094]The SELECT clause of this query contains an identifier 'bean.produktKonfigurationenLocal' that ends in a cmr-field. The EJB 2.1 specification section 11.2.7.1 requires that any related null objects belonging to the set corresponding to this cmr-field must be returned by this query however the database that will be used to execute this query does not sufficiently support SQL outer joins, therefore this query will not return any null objects that might otherwise be returned.
I have no clue what's going on there. Maybe someone can help me out.
Snippet from the ejb-jar.xml Deployment Descriptor:
<ejb-relation id="EJBRelation_9">
<ejb-relation-name>Angebot-ProduktKonfiguration</ejb-relation-name>
<ejb-relationship-role id="EJBRelationshipRole_17">
<ejb-relationship-role-name>ProduktKonfigurationen-Have-Angebote</ejb-relationship-role-name>
<multiplicity>Many</multiplicity>
<relationship-role-source id="RoleSource_17">
<ejb-name>MSProduktKonfiguration</ejb-name>
</relationship-role-source>
<cmr-field id="CMRField_9">
<cmr-field-name>angebotLocal</cmr-field-name>
<cmr-field-type>java.util.Collection</cmr-field-type>
</cmr-field>
</ejb-relationship-role>
<ejb-relationship-role id="EJBRelationshipRole_18">
<ejb-relationship-role-name>Angebote-Have-ProduktKonfigurationen</ejb-relationship-role-name>
<multiplicity>Many</multiplicity>
<relationship-role-source id="RoleSource_18">
<ejb-name>MSAngebot</ejb-name>
</relationship-role-source>
<cmr-field id="CMRField_10">
<cmr-field-name>produktKonfigurationenLocal</cmr-field-name>
<cmr-field-type>java.util.Collection</cmr-field-type>
</cmr-field>
</ejb-relationship-role>
</ejb-relation>
Snippet from the weblogic-cmp-rdbms-jar.xml Deployment Descriptor:
<weblogic-rdbms-relation>
<relation-name>Angebot-ProduktKonfiguration</relation-name>
<table-name>MS_PRODUKT.ANGEBOT_POSITION</table-name>
<weblogic-relationship-role>
<relationship-role-name>Angebote-Have-ProduktKonfigurationen</relationship-role-name>
<relationship-role-map>
<column-map>
<foreign-key-column>angebot_id</foreign-key-column>
<key-column>angebot_id</key-column>
</column-map>
</relationship-role-map>
</weblogic-relationship-role>
<weblogic-relationship-role>
<relationship-role-name>ProduktKonfigurationen-Have-Angebote</relationship-role-name>
<relationship-role-map>
<column-map>
<foreign-key-column>produkt_konfiguration_id</foreign-key-column>
<key-column>produkt_konfiguration_id</key-column>
</column-map>
</relationship-role-map>
</weblogic-relationship-role>
</weblogic-rdbms-relation>
Hi,
There are many differences between EJB 1.1 and 2.0. Most of these are
regarding CMP entity EJBs. I would say you should go with 2.0 if you have
entity EJBs.
Also EJB 2.0 has local interfaces and message-driven beans (JMS listeners).
Emmanuel
"Brian" <[email protected]> wrote in message
news:3cf3b4eb$[email protected]..
>
Our standard development tool here is WebGain Visual Cafe 4.5.1. I am toldthat this
tool does not support EJB 2.0. We are generating EJB's through the wizardbased interface
of Visual Cafe.
Is there a compelling reason to use EJB 2.0 instead of 1.1, even thoughthe tool
doesn't support it? Is the time saved by automatic generation of EJB 1.1beans outweighed
by improvements in EJB 2.0?
Thanks for you help!
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Curious to know whether someone has been able to set up a many to many relationship between two entity beans.
I have been struggling with this for days now and I can't get it to work.
In my test project I have two entity beans, resp. Consultant and Solution.
Consultant has a cmr field called 'solutions', which is a collection object from the opposite side (Solution).
This is the source of the ejb-jar.xml file
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE ejb-jar PUBLIC "-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 2.0//EN" "http://java.sun.com/dtd/ejb-jar_2_0.dtd">
<ejb-jar>
<description>EJB JAR description</description>
<display-name>EJB JAR</display-name>
<enterprise-beans>
<session>
<ejb-name>ProfilerBean</ejb-name>
<home>com.atosorigin.tcc.testing.ejbses.profiling.ProfilerHome</home>
<remote>com.atosorigin.tcc.testing.ejbses.profiling.Profiler</remote>
<local-home>com.atosorigin.tcc.testing.ejbses.profiling.ProfilerLocalHome</local-home>
<local>com.atosorigin.tcc.testing.ejbses.profiling.ProfilerLocal</local>
<ejb-class>com.atosorigin.tcc.testing.ejbses.profiling.ProfilerBean</ejb-class>
<session-type>Stateless</session-type>
<transaction-type>Container</transaction-type>
<ejb-local-ref>
<ejb-ref-name>EJBTesting/Solution</ejb-ref-name>
<ejb-ref-type>Entity</ejb-ref-type>
<local-home>com.atosorigin.tcc.testing.ejbcmp.profiling.SolutionLocalHome</local-home>
<local>com.atosorigin.tcc.testing.ejbcmp.profiling.SolutionLocal</local>
<ejb-link>SolutionBean</ejb-link>
</ejb-local-ref>
<ejb-local-ref>
<ejb-ref-name>EJBTesting/Consultant</ejb-ref-name>
<ejb-ref-type>Entity</ejb-ref-type>
<local-home>com.atosorigin.tcc.testing.ejbcmp.profiling.ConsultantLocalHome</local-home>
<local>com.atosorigin.tcc.testing.ejbcmp.profiling.ConsultantLocal</local>
<ejb-link>ConsultantBean</ejb-link>
</ejb-local-ref>
</session>
<entity>
<ejb-name>ConsultantBean</ejb-name>
<home>com.atosorigin.tcc.testing.ejbcmp.profiling.ConsultantHome</home>
<remote>com.atosorigin.tcc.testing.ejbcmp.profiling.Consultant</remote>
<local-home>com.atosorigin.tcc.testing.ejbcmp.profiling.ConsultantLocalHome</local-home>
<local>com.atosorigin.tcc.testing.ejbcmp.profiling.ConsultantLocal</local>
<ejb-class>com.atosorigin.tcc.testing.ejbcmp.profiling.ConsultantBean</ejb-class>
<persistence-type>Container</persistence-type>
<prim-key-class>java.lang.String</prim-key-class>
<reentrant>False</reentrant>
<cmp-version>2.x</cmp-version>
<abstract-schema-name>Consultant</abstract-schema-name>
<cmp-field>
<field-name>firstname</field-name>
</cmp-field>
<cmp-field>
<field-name>lastname</field-name>
</cmp-field>
<cmp-field>
<field-name>country</field-name>
</cmp-field>
<cmp-field>
<field-name>id</field-name>
</cmp-field>
<primkey-field>id</primkey-field>
<query>
<query-method>
<method-name>findBySolution</method-name>
<method-params>
<method-param>java.lang.String</method-param>
</method-params>
</query-method>
<ejb-ql>SELECT Object(c) FROM Consultant AS c,
IN(c.solutions) s WHERE s.id = ?1 </ejb-ql>
</query>
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<entity>
<ejb-name>SolutionBean</ejb-name>
<home>com.atosorigin.tcc.testing.ejbcmp.profiling.SolutionHome</home>
<remote>com.atosorigin.tcc.testing.ejbcmp.profiling.Solution</remote>
<local-home>com.atosorigin.tcc.testing.ejbcmp.profiling.SolutionLocalHome</local-home>
<local>com.atosorigin.tcc.testing.ejbcmp.profiling.SolutionLocal</local>
<ejb-class>com.atosorigin.tcc.testing.ejbcmp.profiling.SolutionBean</ejb-class>
<persistence-type>Container</persistence-type>
<prim-key-class>java.lang.String</prim-key-class>
<reentrant>False</reentrant>
<cmp-version>2.x</cmp-version>
<abstract-schema-name>Solution</abstract-schema-name>
<cmp-field>
<field-name>description</field-name>
</cmp-field>
<cmp-field>
<field-name>name</field-name>
</cmp-field>
<cmp-field>
<field-name>parent</field-name>
</cmp-field>
<cmp-field>
<field-name>id</field-name>
</cmp-field>
<primkey-field>id</primkey-field>
<query>
<query-method>
<method-name>findChildSolutions</method-name>
<method-params>
<method-param>java.lang.String</method-param>
</method-params>
</query-method>
<ejb-ql>SELECT Object(s) FROM Solution AS s WHERE
s.parent = ?1</ejb-ql>
</query>
<query>
<query-method>
<method-name>findTopLevelSolutions</method-name>
<method-params/>
</query-method>
<ejb-ql>Select Object(s) FROM Solution AS s WHERE
(s.parent = 'none')</ejb-ql>
</query>
</entity>
</enterprise-beans>
<relationships>
<ejb-relation>
<description>A consultant may have one or more areas of expertise</description>
<ejb-relation-name>Consultant_Solutions</ejb-relation-name>
<ejb-relationship-role>
<ejb-relationship-role-name>com.atosorigin.tcc.testing.ejbcmp.profiling.ConsultantBean</ejb-relationship-role-name>
<multiplicity>Many</multiplicity>
<relationship-role-source>
<ejb-name>ConsultantBean</ejb-name>
</relationship-role-source>
<cmr-field>
<cmr-field-name>solutions</cmr-field-name>
<cmr-field-type>java.util.Collection</cmr-field-type>
</cmr-field>
</ejb-relationship-role>
<ejb-relationship-role>
<ejb-relationship-role-name>com.atosorigin.tcc.testing.ejbcmp.profiling.SolutionBean</ejb-relationship-role-name>
<multiplicity>Many</multiplicity>
<relationship-role-source>
<ejb-name>SolutionBean</ejb-name>
</relationship-role-source>
</ejb-relationship-role>
</ejb-relation>
</relationships>
<assembly-descriptor>
<container-transaction>
<description>container-transaction</description>
<method>
<ejb-name>SolutionBean</ejb-name>
<method-name>*</method-name>
</method>
<method>
<ejb-name>ProfilerBean</ejb-name>
<method-name>*</method-name>
</method>
<method>
<ejb-name>ConsultantBean</ejb-name>
<method-name>*</method-name>
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<trans-attribute>Required</trans-attribute>
</container-transaction>
</assembly-descriptor>
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I created a stateless session bean as a business facade for the two entity beans. I then created a webservice to test the beans.
What works :
- create a consultant
- get a consultant
- create a solution
- get a solution
(basically everything that doesn't involve the relationship field.
However, what doesn't work is the method call assignSolution:
- assign solution : this is implemented as follows
Business Method.
public void assignSolution(String consultantID, String solutionID)
throws ProfilingException {
// TODO : Implement
ConsultantLocal cons = null;
SolutionLocal sol = null;
try {
cons = consHome.findByPrimaryKey(consultantID);
sol = solHome.findByPrimaryKey(solutionID);
Collection solutions = cons.getSolutions();
solutions.add(sol);
//sol.getConsultants().add(cons);
} catch (FinderException ex) {
ex.printStackTrace();
throw new ProfilingException("failed to retrieve data from DB", ex);
As you can see I am trying to use the CM Relationship in this methhod. Adding the solution to a consultant should be as simple as adding a solution object to the collection retrieved with the getSolutions accessor. The Container is expected to persist the information in my MAXDB database.
However this doesn't happen.
The ORM details as defined in the persistent.xml follows :
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE persistent-ejb-map SYSTEM "persistent.dtd">
<persistent-ejb-map>
<locking
type="Table"/>
<db-properties>
<data-source-name>TCC_PORTAL_PROFILER</data-source-name>
<database-vendor
name="SAPDB"/>
</db-properties>
<entity-beans>
<entity-bean>
<ejb-name>ConsultantBean</ejb-name>
<table-name>PFL_CONSULTANTS</table-name>
<field-map
key-type="NoKey">
<field-name>firstname</field-name>
<column>
<column-name>FIRSTNAME</column-name>
</column>
</field-map>
<field-map
key-type="NoKey">
<field-name>lastname</field-name>
<column>
<column-name>LASTNAME</column-name>
</column>
</field-map>
<field-map
key-type="NoKey">
<field-name>country</field-name>
<column>
<column-name>COUNTRY</column-name>
</column>
</field-map>
<field-map
key-type="PrimaryKey">
<field-name>id</field-name>
<column>
<column-name>ID</column-name>
</column>
</field-map>
<finder-descriptor>
<method-name>findBySolution</method-name>
<method-params>
<method-param>java.lang.String</method-param>
</method-params>
<load-selected-objects
lock="read"/>
</finder-descriptor>
</entity-bean>
<entity-bean>
<ejb-name>SolutionBean</ejb-name>
<table-name>PFL_SAPSOLUTIONS</table-name>
<field-map
key-type="NoKey">
<field-name>description</field-name>
<column>
<column-name>DESCRIPTION</column-name>
</column>
</field-map>
<field-map
key-type="NoKey">
<field-name>name</field-name>
<column>
<column-name>NAME</column-name>
</column>
</field-map>
<field-map
key-type="NoKey">
<field-name>parent</field-name>
<column>
<column-name>PARENTID</column-name>
</column>
</field-map>
<field-map
key-type="PrimaryKey">
<field-name>id</field-name>
<column>
<column-name>ID</column-name>
</column>
</field-map>
<finder-descriptor>
<method-name>findChildSolutions</method-name>
<method-params>
<method-param>java.lang.String</method-param>
</method-params>
<load-selected-objects
lock="read"/>
</finder-descriptor>
<finder-descriptor>
<method-name>findTopLevelSolutions</method-name>
<method-params/>
<load-selected-objects
lock="read"/>
</finder-descriptor>
</entity-bean>
</entity-beans>
<relationships>
<table-relation>
<help-table>PFL_CONS_SOL_MAP</help-table>
<table-relationship-role
key-type="PrimaryKey">
<ejb-name>ConsultantBean</ejb-name>
<cmr-field>solutions</cmr-field>
<fk-column>
<column-name>CONSULTANTID</column-name>
<pk-field-name>id</pk-field-name>
</fk-column>
</table-relationship-role>
<table-relationship-role
key-type="PrimaryKey">
<ejb-name>SolutionBean</ejb-name>
<fk-column>
<column-name>SOLUTIONID</column-name>
<pk-field-name>id</pk-field-name>
</fk-column>
</table-relationship-role>
</table-relation>
</relationships>
</persistent-ejb-map>
The error in the default trace file when calling the method states, there is an "inconsistency in the number of primary keys". Details follow.
#1.5#000F1F188E5C004400000000000010480003E76C80EFD57A#1098880364327#com.sap.engine.services.ejb#com.atosorigin.tcc/EJBCMPProfilingTest#com.sap.engine.services.ejb#Guest#2####4d2b2370281411d9a40d000f1f188e5c#SAPEngine_Application_Thread[impl:3]_31##0#0#Error##Java###
[EXCEPTION]
#1#com.sap.engine.services.ejb.exceptions.BaseRemoteException: Exception in method assignSolution.
at com.atosorigin.tcc.testing.ejbses.profiling.ProfilerObjectImpl0.assignSolution(ProfilerObjectImpl0.java:822)
at com.atosorigin.tcc.testing.ejbses.profiling.Profiler_Stub.assignSolution(Profiler_Stub.java:533)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at com.sap.engine.services.ejb.session.stateless_sp5.ObjectStubProxyImpl.invoke(ObjectStubProxyImpl.java:187)
at $Proxy73.assignSolution(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at com.sap.engine.services.webservices.runtime.EJBImplementationContainer.invokeMethod(EJBImplementationContainer.java:126)
at com.sap.engine.services.webservices.runtime.RuntimeProcessor.process(RuntimeProcessor.java:146)
at com.sap.engine.services.webservices.runtime.RuntimeProcessor.process(RuntimeProcessor.java:68)
at com.sap.engine.services.webservices.runtime.servlet.ServletDispatcherImpl.doPost(ServletDispatcherImpl.java:92)
at SoapServlet.doPost(SoapServlet.java:51)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at com.sap.engine.services.servlets_jsp.server.HttpHandlerImpl.runServlet(HttpHandlerImpl.java:385)
at com.sap.engine.services.servlets_jsp.server.HttpHandlerImpl.handleRequest(HttpHandlerImpl.java:263)
at com.sap.engine.services.httpserver.server.RequestAnalizer.startServlet(RequestAnalizer.java:339)
at com.sap.engine.services.httpserver.server.RequestAnalizer.startServlet(RequestAnalizer.java:317)
at com.sap.engine.services.httpserver.server.RequestAnalizer.invokeWebContainer(RequestAnalizer.java:810)
at com.sap.engine.services.httpserver.server.RequestAnalizer.handle(RequestAnalizer.java:238)
at com.sap.engine.services.httpserver.server.Client.handle(Client.java:92)
at com.sap.engine.services.httpserver.server.Processor.request(Processor.java:147)
at com.sap.engine.core.service630.context.cluster.session.ApplicationSessionMessageListener.process(ApplicationSessionMessageListener.java:37)
at com.sap.engine.core.cluster.impl6.session.UnorderedChannel$MessageRunner.run(UnorderedChannel.java:71)
at com.sap.engine.core.thread.impl3.ActionObject.run(ActionObject.java:37)
at java.security.AccessController.doPrivileged(Native Method)
at com.sap.engine.core.thread.impl3.SingleThread.execute(SingleThread.java:94)
at com.sap.engine.core.thread.impl3.SingleThread.run(SingleThread.java:162)
Caused by: com.sap.engine.services.applocking.exception.SAPAppLockingIllegalArgumentException: Inconsistency in number of primary keys
at com.sap.engine.services.applocking.TableLockingImpl.getArgument(TableLockingImpl.java:385)
at com.sap.engine.services.applocking.TableLockingImpl.lock(TableLockingImpl.java:128)
at com.sap.engine.services.applocking.TableLockingImpl.lock(TableLockingImpl.java:138)
at com.sap.engine.services.ejb.entity.pm.lock.TableLockingSystem.write(TableLockingSystem.java:82)
at com.sap.engine.services.ejb.entity.pm.PersistentM2M.create(PersistentM2M.java:172)
at com.sap.engine.services.ejb.entity.pm.PersistentCacheM2M.add(PersistentCacheM2M.java:197)
at com.sap.engine.services.ejb.entity.pm.multiple.CollectionM2M.add(CollectionM2M.java:57)
at com.atosorigin.tcc.testing.ejbses.profiling.ProfilerBean.assignSolution(ProfilerBean.java:201)
at com.atosorigin.tcc.testing.ejbses.profiling.ProfilerObjectImpl0.assignSolution(ProfilerObjectImpl0.java:771)
... 32 more
I can't figure out what the problem is with the ORM mapping defined.
On the database level I have three tables. Consultant maps to PFL_CONSULTANT, Solution to PFL_SAPSOLUTIONS. The third table PFL_CONS_SOL_MAP is the help table used for the relationship (having two fields, which are in fact foreign keys from the other two tables to express the assignment of solutions to consultants (where a consultant can have one or more solutions).
ps. : I am running Netweaver Developer Workplace (Netweaver 2004, at stack level 5)
Message was edited by: Theo PaesenHm, after disabling 'automatic locking' it works.
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help, tryed to down load to many Apps at once, ipad froze. dealeted Apps, no longer got internet connection. help
What's your problem is 1) your ipad froze or 2) you now have no internet connection?
Have you restarted/reset your device?
http://support.apple.com/kb/HT1430
https://discussions.apple.com/message/19521062#19521062 -
EJB and many-to-many relationship
I write two CMP Beans userBean and roleBean with many-to-many relationship
userBean:
cmp fields: id,name
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then I add CMR mappings to userBEan nd roleBean
ufter deploying of EJB.jar
in client i wrote:
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TransactionRollbackException because Container try to insert into USER_ROLE
values(5(userid),null(roleid)) but user have no roles
in that situation how can I create user without any roles?
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but I whant 0-n:0-m relationship
I resolve this problem by removing secondary table from sun-cmp-entitymappings.xml
So it works good, but now i dont understand: when i need secondary table mapping if they are not needed for many-to-many relationships -
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I have two EBs related by a one to many relationship. The first of these tables is called Student and has studentId as its key. The second of the tables has a composite key made up of studentID, courseID and semesterID.
However, when the tables are generated in NetBeans 5.5, I find that the Course table has studentID as both a primary key and a foreign key.
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Can anyone advise?
Thanks
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The Student class:
package CBSD_CW;
import java.io.Serializable;
import javax.persistence.*;
import java.util.*;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
@Entity
public class Student_EB implements Serializable {
// Table columns.
@Id
@Column(name = "STUDENT_ID", nullable = false)
private Long studentId; // Student ID. Entity <Student><ID> from file: SampleData.xml.
@Column(name = "FIRST_NAME", length = 50, nullable = true)
private String firstName; // First Name. Entity <Student><FirstName> from file: SampleData.xml.
@Column(name = "LAST_NAME", length = 50, nullable = true)
private String lastName; // Last Name. Entity <Student><LastName> from file: SampleData.xml.
@Column(name = "STUDENT_LEVEL", length = 2, nullable = true)
private String studentLevel; // Student Level. Entity <Student><Level> from file: SampleData.xml.
@Column(name = "PROGRAM_NAME", length = 50, nullable = true)
private String programName; // Program Name. Entity <Student><ProgramName> from file: SampleData.xml.
@Column(name = "PROGRAM_NUMBER", length = 3, nullable = true)
private String programNumber; // Program Number. Entity <Student><ProgramNumber> from file: SampleData.xml.
// 1:M relationship with Course_EB.
@OneToMany(cascade=CascadeType.ALL, mappedBy="student")
private List<Course_EB> courses;
public List<Course_EB> getCourses() {
return courses;
public void setCourses(List<Course_EB> courses) {
this.courses = courses;
// Accessors and mutators.
public Long getId() {
return this.studentId;
public void setId(Long studentId) {
this.studentId = studentId;
public String getFirstName() {
return firstName;
public void setFirstName(String firstName) {
this.firstName = firstName;
public String getLastName() {
return lastName;
public void setLastName(String lastName) {
this.lastName = lastName;
public String getStudentLevel() {
return studentLevel;
public void setStudentLevel(String studentLevel) {
this.studentLevel = studentLevel;
public String getProgramName() {
return programName;
public void setProgramName(String programName) {
this.programName = programName;
public String getProgramNumber() {
return programNumber;
public void setProgramNumber(String programNumber) {
this.programNumber = programNumber;
// Other methods.
public boolean equals(Object obj) {
if (obj == this) {
return (true);
if (!(obj instanceof Student_EB)) {
return (false);
if (obj == null) {
return (false);
Student_EB student = (Student_EB) obj;
return (student.studentId == studentId);
The Course class:
package CBSD_CW;
import javax.persistence.CascadeType;
import javax.persistence.EmbeddedId;
import javax.persistence.Entity;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.ManyToOne;
@Entity
public class Course_EB implements java.io.Serializable {
Course_PK course;
// M:1 relationship with Student_EB.
private Student_EB student;
@ManyToOne(cascade=CascadeType.ALL)
@JoinTable(name = "Student_EB", joinColumns= @JoinColumn(name = "STUDENT_ID", referencedColumnName = "studentId"))
public Student_EB getStudent() {
return (student);
public void setStudent(Student_EB student) {
this.student = student;
// Constructor.
public Course_EB() {
// Accessors and mutators.
@EmbeddedId
public Course_PK getCourse_PK () {
return (course);
public void setCourse_PK(Course_PK course) {
this.course = course;
The Course_PK class:
package CBSD_CW;
import javax.persistence.Column;
import javax.persistence.Embeddable;
@Embeddable
public class Course_PK implements java.io.Serializable {
// Table columns.
@Column(name = "STUDENT_ID", length = 4, nullable = false)
private long studentId; // Student ID. Entity <Student><ID> from file: SampleData.xml.
@Column(name = "COURSE_ID", length = 4, nullable = false)
private String courseId; // Course ID. Entity <Student><Course><Number> from file: SampleData.xml.
@Column(name = "SEMESTER_CODE", length = 3, nullable = false)
private String semesterCode; // Semester Code. Entity <Student><Course><SemesterCode> from file: SampleData.xml.
@Column(name = "GRADE", nullable = true)
private char grade; // Grade. Entity <Student><Course><Grade> from file: SampleData.xml.
// Constructors.
public Course_PK() {
public Course_PK(long studentId, long courseid, String semesterCode) {
this.studentId = studentId;
this.courseId = courseId;
this.semesterCode = semesterCode;
// Accessors and mutators.
public long getStudentId() {
return (studentId);
public void setStudentId(long studentId) {
this.studentId = studentId;
public String getCourseId() {
return (courseId);
public void setId(String courseId) {
this.courseId = courseId;
public String getSemesterCode() {
return (semesterCode);
public void setSemesterCode(String semesterCode) {
this.semesterCode = semesterCode;
public char getGrade() {
return (grade);
public void setGrade(char grade) {
this.grade = grade;
// Other methods.
public boolean equals(Object obj) {
if (obj == this) {
return (true);
if (!(obj instanceof Course_PK)) {
return (false);
if (obj == null) {
return (false);
Course_PK course = (Course_PK) obj;
return ((course.studentId == studentId) &&
(course.courseId.equals(courseId)) &&
(course.semesterCode.equals(semesterCode)) &&
(course.grade == grade));
}Because you have field
@Column(name = "STUDENT_ID", length = 4, nullable = false)
private long studentId; // Student ID. Entity <Student><ID> from file: SampleData.xml.In you Course_PK class. As a primary keys.
An again you are joining it in field
@ManyToOne(cascade=CascadeType.ALL)
@JoinTable(name = "Student_EB", joinColumns= @JoinColumn(name = "STUDENT_ID", referencedColumnName = "studentId"))So it is appearing both inPrimary Key and in Foreign Key. -
Need help mapping one-to-many relationship
[Sorry, inadvertently cross-posted]
Hello,
I have a one-to-many mapping question that's probably a no-brainer for the
experts of the group out there. My problem is that I can't get a collection
of Items for a given Theme to be populated and I don't know if it's a
problem in my system.jdo or in my classes (or both). For example, for Theme
10,
I want a collection of two Items, item_ids 1 and 2.
I have db tables named ITEM and THEME with the following layouts:
ITEM
|==========================================================|
| item_id(pk) | item_name | item_number | theme_id(fk) |
|==========================================================|
| 1 | This is Item1 | 1234 | 10 |
| 2 | This is Item2 | 2954 | 10 |
| 3 | This is Item3 | 2094 | 17 |
| 4 | This is Item4 | 946 | 11 |
| ... |
|==========================================================|
THEME
|=======================================|
| theme_id(pk) | theme_description |
|=======================================|
| 4 | Space |
| 10 | Town |
| 11 | Train |
| 17 | Pirate |
| ... |
|=======================================|
I have two PersistenceCapable classes that map to the above tables:
package com.lego.data;
public class Item
public int item_id;
private String item_number;
private String item_name;
private int theme_id;
public Theme theme;
public String toString()
return
item_number+":"+item_name+":"+theme.getCode()+":"+theme.getDescription();
package com.lego.data;
import java.util.*;
public class Theme
public int theme_id;
public String theme_description;
public Collection items;
public String toString()
return theme_id+":"+theme_description;
and here is my system.jdo file:
<?xml version = "1.0" encoding = "US-ASCII"?>
<jdo>
<package name="com.lego.data">
<class name="Item" identity-type="application"
objectid-class="com.lego.data.IntOId">
<extension vendor-name="kodo" key="table" value="item"/>
<extension vendor-name="kodo" key="lock-column" value="none"/>
<extension vendor-name="kodo" key="class-column" value="none"/>
<field name="item_id" primary-key="true">
<extension vendor-name="kodo" key="data-column" value="item_id"/>
</field>
<field name="item_number">
<extension vendor-name="kodo" key="data-column" value="item_number"/>
</field>
<field name="item_name">
<extension vendor-name="kodo" key="data-column" value="item_name"/>
</field>
<field name="theme_id">
<extension vendor-name="kodo" key="data-column" value="theme_id"/>
</field>
<field name="theme">
<extension vendor-name="kodo" key="theme_id-data-column"
value="theme_id"/>
</field>
</class>
<class name="Theme" identity-type="application"
objectid-class="com.lego.data.ThemeKey">
<extension vendor-name="kodo" key="table" value="theme"/>
<extension vendor-name="kodo" key="lock-column" value="none"/>
<extension vendor-name="kodo" key="class-column" value="none"/>
<field name="theme_id" primary-key="true">
<extension vendor-name="kodo" key="data-column" value="theme_id"/>
</field>
<field name="theme_description">
<extension vendor-name="kodo" key="data-column"
value="theme_description"/>
</field>
<field name="items">
<collection element-type="Item"/>
<extension vendor-name="kodo" key="inverse" value="theme"/>
</field>
</class>
</package>
</jdo>
Thanks in advance for the help.
-TimAbe White wrote:
The first thing to check is that you are always setting the "theme" field in
your Items. If you add an Item i to the "themes" collection of a Theme t, but
forget to also set i's "theme" field to t, then the change will never get
written to the database.
Next, make sure that whenever you set the "theme" field of an Item, you also
set
its "theme_id" field. You map both of these fields to the same column, so you
better be sure they stay in synch.
On a related note, you might try making the "theme_id" field non-persistent if
things still aren't working for you. Mapping two fields to the same column
might be causing trouble. It would be safer to make theme_id non-persistent
anyway, and to always grab the id from the Theme stored in your "theme"
field.
Better OO programming and all that, though I can see that you might have
performance issues in mind when doing it your way.
Anyway, if you find that it works when you make theme_id nonpersistent, let us
know and we'll see why the double-mapping of the column is causing problems,
and hopefully find a fix.Abe,
Thanks for the response but I'm still confused. I failed to mention that
the Item and Theme tables are in an existing schema, so as you saw in my
system.jdo, I am specifying application identity.
Since this is an existing schema, the Item table has theme_id as the
foreign key to the Theme table. So are saying that it is a problem to map
the both theme_id as a data column and a Theme object in the Item at the
same time?
I guess what I don't understand is exactly what my system.jdo should look
like to map a one-to-many relationship. In my case, from Theme (1) to Item
(many). (See my system.jdo in previous post).
Thanks
-Tim -
my i pad is lock can someone please help the password was used to many times
If you have forgotten the iPad passcode and you cannot unlock the device, you have to restore the device within iTunes. You want to use the same computer that you always sync with so that you can restore your iTunes content. You can restore with any other computer, but you will lose everything on the iPad.
Instructions can be found here.
http://support.apple.com/kb/ht1212
You will probably need to restore using Recovery Mode. You can read about it here.
http://support.apple.com/kb/ht4097 -
Problems with EJB Application with many CMP's
I had been working with a Sun engineer in reference to a major problem with a large CMP Module with over 120 cmp beans with many relationships. It was filed as a bug and just recently they released Update 2. I installed this update and now I can build our complete application in Sun 1 Studio 5. Now, there seems to still be a problem in the application module. If we create the application and add our session module, cmp module and web module there is not problems. I can create the ear file and deploy this to S1AS7. Now if I exit the IDE the next time I return the Application shows that there is a error (red error indicator). I cannot expand the application to see the modules. The same problem was in S1S4 but it was not that big of a deal as it allowed you to add the modules back in, save and export the ear. But, now in S1S5 you cannot do a single thing with this module. Even the menu items to delete are not available. The only thing we can to is create the application again and add the modules etc. Also, if I right click on the application and select view error information it does nothing so I cannot even see the error that is causing this trouble. Also, we know it is something with the application and the cmp module because we can add just the web moduel and session module, save, exit and return and the application is fine. It is only when we add in the cmp module that after saving and returning things are wacked.
Has anyone else seen this problem with the application?I have found the error. In the ide log it showed that the entity expansion limit was reached for the DOM parser. I added this to my ide.cfg and all works well now.
-J-DentityExpansionLimit=128000
Apperently the limit is 64000 and with the very large modules it was just not enough. -
Problem with 1-to-many relationship between entity beans
Hi All!
I have two tables TMP_GROUP and TMP_EMPLOYEE with following fields:
TMP_GROUP: ID, CAPTION, COMMENT, STATUS.
TMP_EMPLOYEE: ID, LOGIN, GROUP_ID.
For this tables i create two entity beans GROUP and EMPLOYEE respectively.
The relationship looks like this
descriptor ejb.xml:
<ejb-relation>
<description>description</description>
<ejb-relation-name>employeesOfGroup</ejb-relation-name>
<ejb-relationship-role>
<ejb-relationship-role-name>com.mypackage.GroupBean</ejb-relationship-role-name>
<multiplicity>One</multiplicity>
<relationship-role-source>
<ejb-name>GroupBean</ejb-name>
</relationship-role-source>
<cmr-field>
<cmr-field-name>employees</cmr-field-name>
<cmr-field-type>java.util.Collection</cmr-field-type>
</cmr-field>
</ejb-relationship-role>
<ejb-relationship-role>
<ejb-relationship-role-name>com.mypackage.EmployeeBean</ejb-relationship-role-name>
<multiplicity>Many</multiplicity>
<relationship-role-source>
<ejb-name>EmployeeBean</ejb-name>
</relationship-role-source>
</ejb-relationship-role>
</ejb-relation>
descriptor persistent.xml:
<table-relation>
<table-relationship-role
key-type="PrimaryKey">
<ejb-name>GroupBean</ejb-name>
<cmr-field>employees</cmr-field>
</table-relationship-role>
<table-relationship-role
key-type="NoKey">
<ejb-name>EmployeeBean</ejb-name>
<fk-column>
<column-name>GROUP_ID</column-name>
<pk-field-name>ejb_pk</pk-field-name>
</fk-column>
</table-relationship-role>
</table-relation>
Now i implement business method:
public Long addEmployee(String login, long groupId) {
Long result;
try {
EmployeeLocal employee = employeeHome.create(login);
GroupLocal group =
groupHome.findByPrimaryKey(new Long(groupId));
Collection employees = group.getEmployees();
employees.add(employee);
result = (Long) employee.getPrimaryKey();
} catch (CreateException ex) {
result = new Long(0);
} catch (FinderException ex) {
result = new Long(0);
return result;
When i call this method from web service, the following exception is raised:
com.sap.engine.services.ejb.exceptions.BaseTransactionRolledbackLocalException: Exception in method com.mypackage.GroupLocalHomeImpl0.findByPrimaryKey(java.lang.Object).
P.S.
1) I have transaction attribute set to "Required" for all methods of all beans
2) I have unique index for each table:
TMP_GROUP_I1: CAPTION
TMP_EMPLOYEE_I1: LOGIN (however i think GROUP_ID must be added here too)
3) I tried many:many relationship with this tables and it works fine
4) I try another implementation of addEmployee method with
EmployeeLocal employee = employeeHome.create(login, groupId);
without using GroupLocal cmr-field and GroupLocalHome findByPrimaryKey method, the result is same error.
Can somebody help me with this problem?
Thanks in advance.
Best regards, Abramov Andrey.gimbal2 wrote:
1: The @JoinColumn on the listOfDepartments collection in Company is wrong. It should be something like this for a bidirectional relationship:
@OneToMany(mappedBy="company") // company is the matching property name in Department
private List <Department> listOfDepartment = new ArrayList<Department>();Note that I removed the fetch configuration; onetomany is fetched lazy by design. Saves some clutter eh.
2: use a Set in stead of a List (hibernate doesn't like lists much in entities and will break when you create slightly more complex entity relations)
3: don't just slap cascades on collections, especially of type ALL. Do it with care. In the many years I've been using JPA I've only had to cascade deletes in very specific situations, maybe once or twice. I never needed any of the other cascade types, they just invite sloppy code if you ask me. When working with persistence you should apply a little precision.I made all changes as you mentioned but still compID in department table shows null value... -
Problem with 1:many relationship between entity beans.
Hi All!
I have two tables TMP_GROUP and TMP_EMPLOYEE with following fields:
TMP_GROUP: ID, CAPTION, COMMENT, STATUS.
TMP_EMPLOYEE: ID, LOGIN, GROUP_ID.
For this tables i create two entity beans GROUP and EMPLOYEE respectively.
The relationship looks like this
descriptor ejb.xml:
<ejb-relation>
<description>description</description>
<ejb-relation-name>employeesOfGroup</ejb-relation-name>
<ejb-relationship-role>
<ejb-relationship-role-name>com.mypackage.GroupBean</ejb-relationship-role-name>
<multiplicity>One</multiplicity>
<relationship-role-source>
<ejb-name>GroupBean</ejb-name>
</relationship-role-source>
<cmr-field>
<cmr-field-name>employees</cmr-field-name>
<cmr-field-type>java.util.Collection</cmr-field-type>
</cmr-field>
</ejb-relationship-role>
<ejb-relationship-role>
<ejb-relationship-role-name>com.mypackage.EmployeeBean</ejb-relationship-role-name>
<multiplicity>Many</multiplicity>
<relationship-role-source>
<ejb-name>EmployeeBean</ejb-name>
</relationship-role-source>
</ejb-relationship-role>
</ejb-relation>
descriptor persistent.xml:
<table-relation>
<table-relationship-role
key-type="PrimaryKey">
<ejb-name>GroupBean</ejb-name>
<cmr-field>employees</cmr-field>
</table-relationship-role>
<table-relationship-role
key-type="NoKey">
<ejb-name>EmployeeBean</ejb-name>
<fk-column>
<column-name>GROUP_ID</column-name>
<pk-field-name>ejb_pk</pk-field-name>
</fk-column>
</table-relationship-role>
</table-relation>
Now i implement business method:
public Long addEmployee(String login, long groupId) {
Long result;
try {
EmployeeLocal employee = employeeHome.create(login);
GroupLocal group =
groupHome.findByPrimaryKey(new Long(groupId));
Collection employees = group.getEmployees();
employees.add(employee);
result = (Long) employee.getPrimaryKey();
} catch (CreateException ex) {
result = new Long(0);
} catch (FinderException ex) {
result = new Long(0);
return result;
When i call this method from web service, the following exception is raised:
com.sap.engine.services.ejb.exceptions.BaseTransactionRolledbackLocalException: Exception in method com.mypackage.GroupLocalHomeImpl0.findByPrimaryKey(java.lang.Object).
P.S.
1) I have transaction attribute set to "Required" for all methods of all beans
2) I have unique index for each table:
TMP_GROUP_I1: CAPTION
TMP_EMPLOYEE_I1: LOGIN (however i think GROUP_ID must be added here too)
3) I tried many:many relationship with this tables and it works fine
4) I try another implementation of addEmployee method with
EmployeeLocal employee = employeeHome.create(login, groupId);
without using GroupLocal cmr-field and GroupLocalHome findByPrimaryKey method, the result is same error.
Can somebody help me with this problem?
Thanks in advance.
Best regards, Abramov Andrey.I have posted excerpts from my orion-ejb-jar.xml file in this posting: Problem mapping a 1:M relationship between two entity EJBs w/ a compound PK
Sorry for the duplicate postings, but I was getting errors on the submission.
April -
One to Many relationship in CMP
Hi,
How to create CMP entity bean that can map One To Many relationship?
Thanks.
(Actually, i have post this question in "Java programming" forum becoz i couldn't find the EJB link in forum main page...)Hello Friend,
Go carefully through the RosterApp example in the J2EE tutorial.
It sure is going to help you.
See each and every tab and the values in the deployment tool.
Best of Luck -
Bidirectional many to many relationship ...
Hello Friends !
I want to mapp 2 tables in a bidirectional many to many relationship. kindly help me how can i mapp them. Do i need just LIST collection on both sides or there is something more to do.
in entity class 1
@ManyToMany
private List<Entity1> OneList = new ArrayList<Entity1>();
in Entity class 2
@ManyToMany
private List<Entity2> TwoList = new ArrayList<Entity2>();
Thanks in advance
Regards,
ZeeshanZeeshan
Hi, For a bidirectional @ManyToMany mapping without a @JoinTable specified - you must specify which side is the owning side so that we know who is the owner of the relationship and optionally the fetchType (fetch).
You may refer to the following tutorial that contains a bidirectional @ManyToMany from an entity to itself in my case (same principle for different entity classes).
I arbitrarily chose one side (references) to be the owning relationship (specifies the mapping) and the other (peers) to be the inverse side - where the "mappedBy" attribute is specified that targets the owning side.
You may use any collection for the type depending on your schema - such as whether you allow duplicates etc.. - I return a Set<Cell> collection.
http://wiki.eclipse.org/EclipseLink/Examples/JPA/WebLogic_Web_Tutorial
http://dev.eclipse.org/svnroot/rt/org.eclipse.persistence/trunk/examples/org.eclipse.persistence.example.jpa.server.weblogic.enterpriseEJB/ejbModule/org/eclipse/persistence/example/jpa/server/business/Cell.java
// inverse relationship
// m-m and 1-m do not weave by default
@ManyToMany(mappedBy="references", fetch=FetchType.EAGER)
private Set<Cell> peers;
// owning relationship
@ManyToMany(fetch=FetchType.EAGER)
private Set<Cell> references;
See also p.101-102 of the book "Pro EJB 3"
http://books.google.com/books?id=fVCuB_Xq3pAC&printsec=frontcover&dq=pro+ejb3#PPA101,M1
http://www.amazon.com/Pro-EJB-Java-Persistence-API/dp/1590596455
thank you
/michael
www.eclipselink.org -
Container managed persistance: many-many relationship
Here's the scenario:
table STUDENTS has columns ID, NAME
table CLASSES has columns ID, TITLE
table STUDENT_CLASSES is an intersection table with columns STUDENT, CLASS which are foreign keys to the ID columns in the STUDENTS and CLASSES tables
How do I specify to OC4J that it should use the STUDENT_CLASSES table to facilitate the container managed many-many relationship?Voytek -- I would use the ormap demo (projects to emps relationship) as an example and see what exists from deploying that. I've included the original ejb-jar.xml entry as well as a trimmed down version of the orion-ejb-jar.xml entry. In this case it is the default mapping but what you would need to do is include an orion-ejb-jar.xml with just the parts you want to control.
<ejb-relation>
<ejb-relation-name>Emps-Projects</ejb-relation-name>
<ejb-relationship-role>
<ejb-relationship-role-name>Projects-have-Emps</ejb-relationship-role-name>
<multiplicity>Many</multiplicity>
<relationship-role-source>
<ejb-name>ProjectBean</ejb-name>
</relationship-role-source>
<cmr-field>
<cmr-field-name>employees</cmr-field-name>
<cmr-field-type>java.util.Collection</cmr-field-type>
</cmr-field>
</ejb-relationship-role>
<ejb-relationship-role>
<ejb-relationship-role-name>Emps-have-Projects</ejb-relationship-role-name>
<multiplicity>Many</multiplicity>
<relationship-role-source>
<ejb-name>EmpBean</ejb-name>
</relationship-role-source>
<cmr-field>
<cmr-field-name>projects</cmr-field-name>
<cmr-field-type>java.util.Collection</cmr-field-type>
</cmr-field>
</ejb-relationship-role>
</ejb-relation>
<entity-deployment name="ProjectBean" location="ProjectBean" table="ProjectBean" >
<primkey-mapping>
<cmp-field-mapping name="projectNo" persistence-name="projectNo" />
</primkey-mapping>
<cmp-field-mapping name="projectName" persistence-name="projectName" />
<cmp-field-mapping name="employees">
<collection-mapping table="EmpBean_projects_Proje__296v53">
<primkey-mapping>
<cmp-field-mapping name="ProjectBean_projectNo">
<entity-ref home="ProjectBean">
<cmp-field-mapping name="ProjectBean_projectNo" persistence-name="ProjectBean_projectNo" />
</entity-ref>
</cmp-field-mapping>
</primkey-mapping>
<value-mapping type="hr.EmpLocal">
<cmp-field-mapping name="EmpBean_empNo">
<entity-ref home="EmpBean">
<cmp-field-mapping name="EmpBean_empNo" persistence-name="EmpBean_empNo" />
</entity-ref>
</cmp-field-mapping>
</value-mapping>
</collection-mapping>
</cmp-field-mapping>
... finder methods removed ...
</entity-deployment>
I hope this helps -- Jeff -
ONE-to-MANY relationship between tables and forms in APEX
I recently started using APEX and I have run into an issue.
I have a ONE-TO-MANY relationship between two tables, A1 and A2, respectively.
A1:
A1_ID
Item
A2:
A2_ID
SubItem
A1_ID
I have 2 forms (lets call it F1 and F2) that I use to capture data for A1 and A2.
On F2, I have the following fields that are setup to capture data:
A2.A1_ID
**A1.Item (this is a drop down that is populated using a SELECT statement where the select uses A1.Item field)
A2.SubItem (user would enter SubItem)
Note: A2.A2_ID is populated using a SEQ
Everytime I pick **A1.Item on F2, is there a way to link to A1 table and display A1.A1_ID for every **A1.Item selected on F2?
If so, I want to store the value captured in F2 for the A1_ID field into A2 table to maintain my 1-to-MANY relationship.
If this will work, how do I go about implementing this solution?
Can someone help me?I think it sounds like you are asking for a Master-Detail form. Try that and see what you get.
chris. -
Urgent : java bean having bidirectional one to many relationship
Hi,
We have complex requirement in our application.
We need to copy java bean having bidirectional one to many relationship to another javabean having bidirectional one to many relationship..
E.g
Class Basket1 {
public String color;
pubic String type;
public List<Basket1> basketList = new ArrayList()
Class Basket2 {
public String color;
pubic String type;
public List<Basket2> basketList = new ArrayList()
We need to exact copy Basket1 to Basket2. We are in trouble to copy List of child because we do not have how many child Basket1 have of same type..
Can someone help us how we can implement such kind of complex object bidirectional one to many relationship??I can't see anything bidirectional about these relationships. What I can see is a couple of BasketN classes that look identical so I don't know why they both exist, and they both contain lists of themselves as members, which suggests some kind of tree structure. Nothing bidirectional there. I can see tat these things can form circular object graphs but I don't see why you would want to do that.
We need to exact copy Basket1 to Basket2And I don't know what that means. Please explain.
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