Could not convert org.apache.axis.attachments.AttachmentPart

[Rudolf Pailer <r....@a1.net>]

Hello!

I have been struggeling with implementing an MMS receiver according to the
MM7 specification.

3GPP's MM7 interface defines an MM7 XML schema (namespace is
http://www.3gpp.org/ftp/Specs/archive/23_series/23.140/schema/REL-6-MM7-1-0)
that contains the following element:

	<xsd:complexType name="contentReferenceType">
		<xsd:annotation>
			<xsd:documentation>content element including only
href</xsd:documentation>
		</xsd:annotation>
		<xsd:attribute name="href" type="xsd:anyURI"
use="required"/>
		<xsd:attribute name="allowAdaptations" type="xsd:boolean"
use="optional"/>
	</xsd:complexType>

This element contains a cid: URL that points to a MIME content in a SOAP
with attachment message:
   <Content allowAdaptations="false"
href="cid:C1AB4727D0BBEC9380615FDACADBE956"/>


When importing this schema into a WSDL file and generating Java classes with
WSDL2JAVA for the use on the server side, one gets the following Exception,
when the service is called by a SOAP request containing an attachment:

[26.07.06 10:03:31:163 CEST]  3410b26 BeanPropertyT E
org.apache.axis.encoding.ser.BeanPropertyTarget  Could not convert
org.apache.axis.attachments.AttachmentPart to bean field 'content', type
at.mobilkom.asmp.mm7.wsdl.ContentReferenceType
[26.07.06 10:03:31:173 CEST]  3410b26 EXCEPTIONS    I
org.apache.axis.EXCEPTIONS  AxisFault:
[26.07.06 10:03:31:273 CEST]  3410b26 EXCEPTIONS    I
org.apache.axis.EXCEPTIONS  TRAS0014I: Die folgende Ausnahmebedingung wurde
protokolliert: AxisFault
 faultCode: {http://schemas.xmlsoap.org/soap/envelope/}Server.userException
 faultSubcode: 
 faultString: java.lang.IllegalArgumentException: argument type mismatch
 faultActor: 
 faultNode: 
 faultDetail: 
	
{http://xml.apache.org/axis/}stackTrace:java.lang.IllegalArgumentException:
argument type mismatch
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:85
)
	at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:58
)
	at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl
.java:60)
	at java.lang.reflect.Method.invoke(Method.java:391)
	at
org.apache.axis.utils.BeanPropertyDescriptor.set(BeanPropertyDescriptor.java
:142)
	at
org.apache.axis.encoding.ser.BeanPropertyTarget.set(BeanPropertyTarget.java:
75)
	at
org.apache.axis.encoding.DeserializerImpl.valueComplete(DeserializerImpl.jav
a:249)
	at
org.apache.axis.encoding.DeserializerImpl.startElement(DeserializerImpl.java
:388)
	at
org.apache.axis.encoding.DeserializationContext.startElement(Deserialization
Context.java:1048)
	at
org.apache.axis.message.SAX2EventRecorder.replay(SAX2EventRecorder.java:165)
	at
org.apache.axis.message.MessageElement.publishToHandler(MessageElement.java:
1141)
	at
org.apache.axis.message.RPCElement.deserialize(RPCElement.java:236)
	at org.apache.axis.message.RPCElement.getParams(RPCElement.java:384)
	at
org.apache.axis.providers.java.RPCProvider.processMessage(RPCProvider.java:8
1)
	at
org.apache.axis.providers.java.JavaProvider.invoke(JavaProvider.java:323)
	at
org.apache.axis.strategies.InvocationStrategy.visit(InvocationStrategy.java:
32)
	at org.apache.axis.SimpleChain.doVisiting(SimpleChain.java:118)
	at org.apache.axis.SimpleChain.invoke(SimpleChain.java:83)
	at
org.apache.axis.handlers.soap.SOAPService.invoke(SOAPService.java:453)
	at org.apache.axis.server.AxisServer.invoke(AxisServer.java:281)
	at
org.apache.axis.transport.http.AxisServlet.doPost(AxisServlet.java:699)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)
	at
org.apache.axis.transport.http.AxisServletBase.service(AxisServletBase.java:
327)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
	at
com.ibm.ws.webcontainer.servlet.StrictServletInstance.doService(StrictServle
tInstance.java:110)
	at
com.ibm.ws.webcontainer.servlet.StrictLifecycleServlet._service(StrictLifecy
cleServlet.java:174)
	at
com.ibm.ws.webcontainer.servlet.IdleServletState.service(StrictLifecycleServ
let.java:313)
	at
com.ibm.ws.webcontainer.servlet.StrictLifecycleServlet.service(StrictLifecyc
leServlet.java:116)
	at
com.ibm.ws.webcontainer.servlet.ServletInstance.service(ServletInstance.java
:283)
	at
com.ibm.ws.webcontainer.servlet.ValidServletReferenceState.dispatch(ValidSer
vletReferenceState.java:42)
	at
com.ibm.ws.webcontainer.servlet.ServletInstanceReference.dispatch(ServletIns
tanceReference.java:40)
	at
com.ibm.ws.webcontainer.webapp.WebAppRequestDispatcher.handleWebAppDispatch(
WebAppRequestDispatcher.java:1019)
	at
com.ibm.ws.webcontainer.webapp.WebAppRequestDispatcher.dispatch(WebAppReques
tDispatcher.java:592)
	at
com.ibm.ws.webcontainer.webapp.WebAppRequestDispatcher.forward(WebAppRequest
Dispatcher.java:204)
	at
com.ibm.ws.webcontainer.srt.WebAppInvoker.doForward(WebAppInvoker.java:125)
	at
com.ibm.ws.webcontainer.srt.WebAppInvoker.handleInvocationHook(WebAppInvoker
.java:286)
	at
com.ibm.ws.webcontainer.cache.invocation.CachedInvocation.handleInvocation(C
achedInvocation.java:71)
	at
com.ibm.ws.webcontainer.srp.ServletRequestProcessor.dispatchByURI(ServletReq
uestProcessor.java:182)
	at
com.ibm.ws.webcontainer.oselistener.OSEListenerDispatcher.service(OSEListene
r.java:334)
	at
com.ibm.ws.webcontainer.http.HttpConnection.handleRequest(HttpConnection.jav
a:56)
	at
com.ibm.ws.http.HttpConnection.readAndHandleRequest(HttpConnection.java:615)
	at com.ibm.ws.http.HttpConnection.run(HttpConnection.java:439)
	at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:912)


The reason for this is rooted in the
org.apache.axis.encoding.DeserializerImpl class in method startElement():

Here it is detected that the element references an AttachmentPart and the
following code gets executed:

                if( !href.startsWith("#") && defaultType != null && ref
instanceof Part ){
                    //For attachments this is the end of the road-- invoke
deserializer
                    Deserializer dser =
context.getDeserializerForType(defaultType );
                    if(null != dser){          
                      dser.startElement(namespace, localName,
                             prefix, attributes,
                             context);
                      ref = dser.getValue();       
                    }
               }

The default type is imlpemented by a BeanDeserialize, that gets called with
startElement(). BeanDeserialzer extends DeserializerImpl and
BeanDeserialzer.startElement() calls super.startElement(). Thus
DeserializerImpl.startElement() gets called a second time and returns again
an AttachmentPart as object reference (as there is sill the href attribute).
The BeanPropertyTarget.set() method later on tries to set the Java Bean with
an AttachmentPart and fails with above exception.

I have quickly solved this bug by adding to the classes Deserializer,
DeserializerImpl and BeanDeserialzer the method

    public void startElement(String namespace, String localName,
            String qName, Attributes attributes,
            DeserializationContext context, boolean ignoreHref)
    throws SAXException;
    
where the existing code calls now

    public void startElement(String namespace, String localName,
            String prefix, Attributes attributes,
            DeserializationContext context)
    throws SAXException
    {
       startElement(namespace, localName, prefix, attributes, context,
false);
    }


In DeserializerImpl.startElement() I have extended the href check by:

        String href = attributes.getValue(soapConstants.getAttrHref());
        if (href != null && !ignoreHref) {
        
This may not be the most elegant solution, but it works.

It would be very nice, if one of the Axis gurus could confirm, that this is
indeed a bug and perhaps propose some good solution.

regards
Rudolf