I have an EAR project. In the project I have a web app and an EJB. My goal
is to have a REST webservice servlet that gets the XML payload, uses JAXB
to unmarshal it into XJC generated classes, then pass those classes to an
EJB for processing. What I have found is the following:
scenario 1)
here is the EAR fle structure:
EAR
bpo-lib.jar - holds the XJC generated classes
bpo-ejb.jar - references bpo-lib.jar in its manifest.mf file
bpo-webservice.war - holds the rest servlet that does the
unmarshaling and passes unmarshaled objects to EJB
- holds bpo-lib.jar in WEB-INF/lib - I did this
because I saw in the FAQ that JAXBContext.newInstance tries to load
classes using the same clasloader that the
JAXBContext class is in
- references bpo-lib.jar in its manifest.mf
file
The result is that I can unmarshal the data into the XJC classes, but
after I pass them to the EJB, I try to cast the object into the expected
types and get a class cast exception. this is possibly the behavior
mentioned in
https://jaxb.dev.java.net/faq/#classloader
scenario 2)
here is the EAR file structure:
EAR
bpo-lib.jar - holds the XJC generated classes
bpo-ejb.jar - references bpo-lib.jar in its manifest.mf file
bpo-webservice.war - holds the rest servlet that does the
unmarshaling and passes unmarshaled objects to EJB
- does NOT hold bpo-lib.jar in WEB-INF/lib - I
did this because in theory, on JBOSS4.0.4GA,
the EAR classes are accessible to the WAR
context. I.E., I should NOT have to put the bpo-lib.jar file
in both the WEB-INF/lib dir and the EAR file
- references bpo-lib.jar in its manifest.mf file
The result is that I can NOT unmarshal the data into the XJC classes.
To analyze this, I checked what classes the JAXBContext knows about, and
what I found was that when it unmarshalled data, I had this set of
classes:
boolean
byte
char
com.homeq.bpo.domain.FirstAmericanSchema.request.AppraisalStatusResponses
com.homeq.bpo.domain.FirstAmericanSchema.request.AppraisalStatusResponses$AppraisalStatusResponse
com.homeq.bpo.domain.FirstAmericanSchema.request.AppraisalStatusResponses$AppraisalStatusResponse$Notes
com.homeq.bpo.domain.FirstAmericanSchema.request.NoteType
com.homeq.bpo.domain.FirstAmericanSchema.request.ResultsDataType
com.sun.xml.bind.api.CompositeStructure
double
.
.
.
When it did not unmarshal data it had this set of classes:
boolean
byte
char
com.homeq.bpo.domain.FirstAmericanSchema.request.ObjectFactory
com.sun.xml.bind.api.CompositeStructure
double
float
.
.
.
The above shows (I think) that I MUST have the bpo-lib.jar in the
WEB-INF/lib dir as the classloader that loads JAXBContext must also load
the generated classes. But as shown in scenario 1 above, this prevents you
from also referencing those classes in an EJB, because, as stated in the
FAQ, you get a classCast exception
Would I be correct in stating that using JAXB in a rest based web service
on JBOSS4.0.4GA cannot be done, or am I missing something?