hbm2java gives NullPointerException

dmitrij · **Joined:** Mon Apr 12, 2004 3:25 pm **Posts:** 2

Dear All,

I am new both to java and hibernate, so maybe I overlooked something trivial. hbm2java is so new that google returns only 6 pages .-)

I am trying to generate java code from a truly minimal xbm file (see below). I also tried a couple of other xbm files downloaded from various tutorials. My command line is:

/tmp> java net.sf.hibernate.tool.hbm2java.CodeGenerator BlastHit.hbm.xml
INFO - Generating 1 in generated
java.lang.NullPointerException
at net.sf.hibernate.tool.hbm2java.BasicRenderer.isPropertySet(BasicRenderer.java:611)
at net.sf.hibernate.tool.hbm2java.BasicRenderer.generateConcreteEmptyClasses(BasicRenderer.java:332)
at net.sf.hibernate.tool.hbm2java.BasicRenderer.render(BasicRenderer.java:59)
at net.sf.hibernate.tool.hbm2java.Generator.write(Generator.java:138)
at net.sf.hibernate.tool.hbm2java.Generator.writeRecur(Generator.java:115)
at net.sf.hibernate.tool.hbm2java.Generator.generate(Generator.java:104)
at net.sf.hibernate.tool.hbm2java.CodeGenerator.main(CodeGenerator.java:125)

The file BlastHit.java is created but contains zero bytes. What I am doing wrong?

Any help will be greatly appreciated.

Dmitrij

------------ BlastHit.hbm.xml --------------------

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">

<hibernate-mapping>

<class name="BlastHit" table="blast">
<id name="id" type="long">
<generator class="increment"/>
</id>
<property name="code" type="string" column="code"/>
</class>

</hibernate-mapping>

max · **Posted:** Mon Apr 12, 2004 5:41 pm

arh darn - i've found the bug in the default configuration of hbmj2ava ;(

if you use the --config option then there should be no problems

dmitrij · **Joined:** Mon Apr 12, 2004 3:25 pm **Posts:** 2

max wrote:

arh darn - i've found the bug in the default configuration of hbmj2ava ;(

if you use the --config option then there should be no problems

Thank you, max. I tried it, but unfortunately it did not help:

/tmp> java net.sf.hibernate.tool.hbm2java.CodeGenerator --config BlastHit.hbm.xml
INFO - Generating 1 in generated
java.lang.NullPointerException
at net.sf.hibernate.tool.hbm2java.BasicRenderer.isPropertySet(BasicRenderer.java:611)
at net.sf.hibernate.tool.hbm2java.BasicRenderer.generateConcreteEmptyClasses(BasicRenderer.java:332)
at net.sf.hibernate.tool.hbm2java.BasicRenderer.render(BasicRenderer.java:59)
at net.sf.hibernate.tool.hbm2java.Generator.write(Generator.java:138)
at net.sf.hibernate.tool.hbm2java.Generator.writeRecur(Generator.java:115)
at net.sf.hibernate.tool.hbm2java.Generator.generate(Generator.java:104)
at net.sf.hibernate.tool.hbm2java.CodeGenerator.main(CodeGenerator.java:125)

Any other suggestions?

Regards,
Dmitrij

max · **Posted:** Mon Apr 12, 2004 6:04 pm

read the docs about --config. it neat's a hbm2java config file as input!

wiverson · **Joined:** Fri Feb 27, 2004 6:17 pm **Posts:** 11

I just ran into this one as well. I used the default config.xml at http://www.hibernate.org/hib_docs/reference/html/toolsetguide.html#toolsetguide-s2-1

I named it hbm2java_config.xml.

I just went looking through the docs, and I didn't realize that there was an Ant task for hbm2java. Was this a recent addition? Very nice...

Since I had to touch this stuff anyways to put in the config element, I went ahead and switched to the Ant task (instead of just calling the hbm2java main from my build.xml).

Here it is, in case anyone finds it useful. :)

Code:

<target name="build_hbm" description="builds the Java sources">
   <mkdir dir="${build.src.dir}"/>
   <echo message="src dir = ${build.src.dir}"/>
   <echo message="target hbm files = ${build.hbm.dir}${package.dir}\" />

   <taskdef name="hbm2java"
       classname="net.sf.hibernate.tool.hbm2java.Hbm2JavaTask">
      <classpath>
         <pathelement 
            location="${hibernate_path}\hibernate2.jar"/>
         <pathelement 
         location="${hibernate_tool_path}\hibernate-tools.jar"/>
         <pathelement 
         location="${hibernate_path}\lib\commons-collections-2.1.jar" />
         <pathelement 
         location="${hibernate_path}\lib\commons-logging-1.0.3.jar" />
         <pathelement 
         location="${hibernate_path}\lib\commons-lang-1.0.1.jar" />
         <pathelement location="${hibernate_path}\lib\xerces-2.4.0.jar" />
         <pathelement location="${hibernate_tool_path}\lib\jdom.jar"/>
      </classpath>
   </taskdef>

   <hbm2java config="hbm2java_config.xml" output="${build.src.dir}">
      <fileset dir="${build.hbm.dir}${package.dir}" includes="*.hbm.xml"/>
   </hbm2java>
</target>

wiverson · **Joined:** Fri Feb 27, 2004 6:17 pm **Posts:** 11

dmitrij - the hbm2java config file isn't an hbm.xml file, it's a different XML file (per the docs).