HBM2DDL fails on <composite-element>

akrk1986 · **Posted:** Wed Nov 19, 2008 11:00 am

I am trying to port my hibernate application from Oracle to DB2.
I created a minimal hibernate.properties file (that contains the dialect specification), put all the necessary JAR files in the classpath and ran the tool on all the *.hbm.xml files.
Everything works fine until it tries to process an hbm file that has the following code (which is exactly as explained in section 8.2 in the Hibernate Reference manual):

Code:

<set    name="workingItems"
        lazy="true"
   table="MA_COMMAND_WORKING_ITEM">
   <key column="COMMAND_ID"/>
   <composite-element class="com.acme.data.pojo.ManagementAuthorityCommandWorkingItem">
        <property name="id" column="ID" not-null="true"/>
        <property name="action" column="ACTION" not-null="true"/>
        <property name="workingItemId" column="WORKING_ITEM_ID" not-null="true"/>
   </composite-element>         
</set>

I do NOT have the class listed in the <composite-element> as this is not needed and works fine with my code.
Here is the output from the tool:

Code:

SEVERE: Error creating schema 
org.hibernate.MappingException: class com.acme.data.pojo.ManagementAuthorityCommandWorkingItem not found while looking for property: id
   at org.hibernate.util.ReflectHelper.reflectedPropertyClass(ReflectHelper.java:74)
   at org.hibernate.mapping.SimpleValue.setTypeUsingReflection(SimpleValue.java:276)
   at org.hibernate.cfg.HbmBinder.createProperty(HbmBinder.java:2164)
   at org.hibernate.cfg.HbmBinder.bindComponent(HbmBinder.java:1893)
   at org.hibernate.cfg.HbmBinder.bindComposite(HbmBinder.java:1692)
   at org.hibernate.cfg.HbmBinder.bindCollectionSecondPass(HbmBinder.java:2448)
   at org.hibernate.cfg.HbmBinder$CollectionSecondPass.secondPass(HbmBinder.java:2652)
   at org.hibernate.cfg.CollectionSecondPass.doSecondPass(CollectionSecondPass.java:43)
   at org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1054)
   at org.hibernate.cfg.Configuration.generateDropSchemaScript(Configuration.java:687)
   at org.hibernate.tool.hbm2ddl.SchemaExport.<init>(SchemaExport.java:93)
   at org.hibernate.tool.hbm2ddl.SchemaExport.<init>(SchemaExport.java:61)
   at org.hibernate.tool.hbm2ddl.SchemaExport.main(SchemaExport.java:394)
Caused by: java.lang.ClassNotFoundException: com.acme.data.pojo.ManagementAuthorityCommandWorkingItem
   at java.net.URLClassLoader$1.run(Unknown Source)
   at java.security.AccessController.doPrivileged(Native Method)
   at java.net.URLClassLoader.findClass(Unknown Source)
   at java.lang.ClassLoader.loadClass(Unknown Source)
   at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
   at java.lang.ClassLoader.loadClass(Unknown Source)
   at java.lang.ClassLoader.loadClassInternal(Unknown Source)
   at java.lang.Class.forName0(Native Method)
   at java.lang.Class.forName(Unknown Source)
   at org.hibernate.util.ReflectHelper.classForName(ReflectHelper.java:100)
   at org.hibernate.util.ReflectHelper.reflectedPropertyClass(ReflectHelper.java:70)
   ... 12 more

[/code]

Any help, pointers, RTFM's are welcome.

max · **Posted:** Thu Nov 20, 2008 10:18 am

how are you running this ?

akrk1986 · **Posted:** Thu Nov 20, 2008 11:01 am

Code:

@echo off
REM
REM Set up CLASSPATH of all JAR files needed by hbm2ddl
REM

set JBLIB=%JBOSS_HOME%\server\default\lib

set HCFG=".\hibernate.cfg.xml"

set A01=.\hibernate3.jar
set A02=%JBLIB%\commons-logging.jar
set A03=%JBLIB%\dom4j.jar
set A04=%JBLIB%\commons-collections.jar

set CLASSPATH=%A01%;%A02%;%A03%;%A04%

java org.hibernate.tool.hbm2ddl.SchemaExport   --text  --properties=hibernate.properties --output=zzz.sql *.hbm.xml 

max · **Posted:** Thu Nov 20, 2008 11:17 am

how are you running this ?

akrk1986 · **Posted:** Thu Nov 20, 2008 11:24 am

max wrote:

how are you running this ?

I start a DOS command window in the folder where all the HBM.XML files are. As I posted earlier, in the script, all the necessary JARs are in the CLASSPATH, so that is not the problem - the problem seems to be in one specific HBM file with the <composite-element> tag.

max · **Posted:** Thu Nov 20, 2008 12:38 pm

I don't see any references to user classes in your classpath.

p.s. Adding a lib directory to a classpath does not automatically add all *.jar's in it

akrk1986 · **Posted:** Thu Nov 20, 2008 1:17 pm

max wrote:

I don't see any references to user classes in your classpath.

p.s. Adding a lib directory to a classpath does not automatically add all *.jar's in it

1. My understanding is that HBM2DDL does not need my classes, only my HBM files
2. The tool was successful on all HBM files except the one that has the <composite-element>. I guess this proves my point...(or maybe not?)

max · **Posted:** Fri Nov 21, 2008 4:20 am

since you haven't listed any type info on your nested properties hibernate need to look up the type on the class - how else would it know what type to put in the database schema ?

So yes, it can work without classes but then you have to put types on all your hbm.xml files.