OneToMany resulting in null field.

Question

I'm attempting to implement the code example from the NetBeans magazine (Nov 2006) using NetBeans 6.0 beta 2 with glassfish-v2 -b58g. It's using a simple db structure with 3 tables:
[Platform] ---- [JSR] 1----* [Package]
I'm running into a problem with the 1 to many between JSR and Package.
The end result is that the jsr field in the inserted Package row is null.
Here's the JSR class (relevant pieces only, hopefully)
@Entity
public class JSR implements Serializable
private List<Package> packages;
@OneToMany(fetch=FetchType.EAGER, cascade=CascadeType.ALL,
mappedBy="jsr")
public List<Package> getPackages()
return packages;
public void setPackages(List<Package> packages)
this.packages = packages;
Here's the Package class
@Entity
public class Package implements Serializable
private JSR jsr;
@ManyToOne
public JSR getJsr()
return jsr;
public void setJsr(JSR jsr)
this.jsr = jsr;
Here's the code from a session bean that enters the data:
@Stateless
public class JavaPlatformManagerBean
implements JavaPlatformManagerRemote,
JavaPlatformManagerLocal
@PersistenceContext
private EntityManager em;
public void createPlatform(Platform platform)
em.merge(platform);
The code that calls the session bean (from a jsp backing bean)
public class JPMClient
@EJB
private JavaPlatformManagerRemote jpm;
public void createJavaSE()
JSR jsr1 = new JSR(176,
"Java SE 5 Release Contents",
new Package ("java.lang"),
new Package ("java.util"),
new Package ("java.sql"));
JSR jsr2 = new JSR(166,
"Concurrency Utilities",
new Package ("java.util.concurrent"));
Platform platform = new Platform ("Java SE 5", jsr1, jsr2);
jpm.createPlatform(platform);
And the results of quering the table (in Derby)
PACKAGE JSR_NUM
java.util.concurrent NULL
java.sql NULL
java.lang NULL
java.util NULL
I know this is long winded, but what am I missing in the JSR/Package classes such that the relationship back to the JSR is null?
Thanks for any insight.
GregM

Answer 1

Unfortunately, AMF serialization is something of a black art. I'd run into multiple issues in the past (working with Granite DS, rather than Blaze--but it's essentially the same thing). I'm not sure about Blaze, but Granite has very verbose logging available if you configure log4j to DEBUG level for org.granite. The other alternative is to attach to your Java process with a debugger (Eclipse makes this fairly automagical), download the Blaze source and configure Blaze as a project in Eclipse, add it to source lookup for your project, and step through the actual serialization to see what's going on. This is moderately complicated to set up, but priceless when it comes to debugging.