EjbCreate() architecture with CMP 2.0; confused

Question

I exhaustively searched for this topic in this, and other forums, and
tried some suggested techniques, but none worked.
I've received "Primary key fields of bean not initialized" in     the following stmt.
     Entity1Remote prEntity1Remote = printHome.create( new Integer(1) );     <-- should parm. list be empty??
RemoteClient1.java contains:
     package com.zbeans;
     import com.zbeans.Entity1Remote;
     import com.zbeans.Entity1RemoteHome;
     import javax.naming.InitialContext;
     Context prinitctx = new InitialContext();
     Context prenvctx = (Context) prinitctx.lookup("java:comp/env");
     Object prrefHome = prenvctx.lookup("ejb/Entity1 EJB ref1");
     Entity1RemoteHome printHome = (Entity1RemoteHome)
          PortableRemoteObject.narrow( prrefHome, Entity1RemoteHome.class );
     /* Following causes "Primary key fields of bean not initialized" */
     Entity1Remote prEntity1Remote = printHome.create( new Integer(1) );     <-- should parm. list be empty??
     I ran using D:\zJava\zsamples\EJB\application1>C:\j2sdkee1.3.1\bin\runclient -client application1.ear -name RemoteClient1 -textauth
     I ensured j2ee and cloudscape were running, and
     set APPCPATH=application1Client.jar     (application1Client.jar was generated by the deployment tool)
The bean code contains:
     package com.zbeans;
     import javax.ejb.*;
     public abstract class Entity1Bean implements javax.ejb.EntityBean {
          public Integer property1;     /* primary key (all lower case, unless that
               breaches naming conventions?). All letters s/b in lower case to
               exactly match non-capitalization of primary key in deployment tool?? */
          /* Must the parm. variable be identically named as the primary key name?? */
          public Integer ejbCreate(Integer property1) throws EJBException, CreateException {
          //public Integer ejbCreate(Integer pnNewProperty1) throws EJBException, CreateException {
          //public void ejbCreate(Integer pnNewProperty1) throws EJBException, CreateException {
               System.out.println("\nInside Entity1Bean.ejbCreate()");     <-- this stmt. was reached
               this.property1 = property1;
               //property1 = pnNewProperty1;
               /* return pnNewProperty1; or return Property1?? should return null for
                    CMP 2.0?? I don't     think so */
               return property1;
          }     // ejbCreate() method
          public abstract Integer getProperty1();
          public abstract void setProperty1(Integer pnNewProperty1);
Entity1RemoteHome.java contains:
     package com.zbeans;
     import java.rmi.RemoteException;
     import javax.ejb.*;
     public interface Entity1RemoteHome extends javax.ejb.EJBHome {
     public Entity1Remote create (Integer property1)
          throws CreateException, RemoteException, EJBException;
Remote1Client1, Entity1RemoteHome.java, etc. resides under d:\zjava\zsamples\com\zbeans
Unsuccessful remedies:
     1) in Entity1Bean
     public Integer ejbCreate(Integer id) throws javax.ejb.CreateException {
     coded
          return id;
     instead of
          return null;
     - some newsgroup posting states that for EJB 2.0 CMP must return Primary key
          type, while others disagree (refer below)
2)
     defined ejbCreate() return type as void instead of Integer,
     and commented out return stmt. i.e.
     public void ejbCreate(Integer id)
          //return null;
     - instead of -
     public Integer ejbCreate(Integer id)
          return null;
     - this compiled clean with javac, but in deployment tool system.err
     contained:
     Entity1Bean_PM.java:76: illegal start of expression return (void)
     partition.afterEjbCreate(this); ^
     c:\j2sdkee1.3.1\repository\computer\gnrtrTMP\application1\com\zbeans\Entity1Bean_PM.
     java:76: ')' expected return (void) partition.afterEjbCreate(this);
     c:\j2sdkee1.3.1\repository\computer\gnrtrTMP\application1\com\zbeans\Entity1Bean_PM.
     java:76: cannot return a value from method whose result type is void
     return (void) partition.afterEjbCreate(this); ^
3) property1 is actually the Integer primary key in deployment tool, so tried the
following
     public Integer Property1;     /* primary key; all letter s/b in lower case to
          exactly match capitalization in deployment tool?? */
     public Integer ejbCreate(Integer pnNewProperty1) throws EJBException, CreateException {
          Property1 = pnNewProperty1;
          return pnNewProperty1;
     }     // ejbCreate() method
4) as above, but typed property1 all in lower case so it would match the
non-capitalization of the primary key in the deployment tool i.e.
     public Integer property1;     /* primary key; all letter s/b in lower case to
          exactly match capitalization in deployment tool?? */
     public Integer ejbCreate(Integer pnNewProperty1) throws EJBException, CreateException {
          property1 = pnNewProperty1;
          return pnNewProperty1;
     }     // ejbCreate() method
5) as above, but made the parm. variable identically named as the
primary key name, and modifed return stmt. i.e.
     public Integer ejbCreate(Integer property1) throws EJBException, CreateException {     
          this.property1 = property1;
          return property1;          /* removing this return caused " missing return
               statement" */
     }     // ejbCreate() method
My environment settings are:
     java version "1.4.0_01"
     Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0_01-b03)
     Java HotSpot(TM) Client VM (build 1.4.0_01-b03, mixed mode)
     WinNT 4.0 SP5
     CLASSESDIR=c:\j2sdkee1.3.1\lib\classes
     CLASSPATH=.;c:\j2sdkee1.3.1\lib\j2ee.jar;D:\jakarta-tomcat-3.3.1\lib\common\serv
     let.jar;C:\JRun4\servers\default\default-ear\default-war\WEB-INF\classes;D:\zJav
     a\zsamples\EJB\application1
     J2EEJARS=c:\j2sdkee1.3.1\lib\j2ee.jar
     J2EETOOL_CLASSES=c:\j2sdkee1.3.1\lib\toolclasses
     J2EETOOL_JAR=c:\j2sdkee1.3.1\lib\j2eetools.jar
     J2EE_HOME=c:\j2sdkee1.3.1
     JAVA_HOME=C:\j2sdk1.4.0_01
     etc.
My understanding was that for CMP2.0, ejbCreate() should accept a parm.
and return the primary key type? For my application, CMP 2.0 is
specified in the J2EE deploytool. I'm really getting confused on the
correct rules for developing the ejbCreate() in CMP 2.0 vs BMP, I've
read conflicting postings.
Instead of the J2EE Deployment Tool, am I better off learning another
server/deployer, such as JBoss, VisualAge for CSP, etc.?

Answer 1

I have noticed two bugs in your code:
1) You should ALWAYS use abstract get/set methods to modify CMP fields
of EJB 2.0 CMP entity bean.
Instead of
this.property1 = property1;call
setProperty1(Integer pnNewProperty1);2) you should return null in ejbCreate() method
"The entity object created by the ejbCreate<METHOD> method must have a unique primary
key. This means that the primary key must be different from the primary keys of all the existing
entity objects within the same home. However, it is legal to reuse the primary key of a previously
removed entity object. The implementation of the Bean Provider?s ejbCreate<
METHOD>(...) methods should be coded to return a null.[14]"
I hope it helps
Maris Orbidans