trouble with deserialization of arrays

[jpowerwa]

I have a web service using JBoss 4.0.2. I am generating the WSDL and jax-rpc mapping file using wscompile in rpc/literal mode. I am having problems on the server with the deserialization of objects that contain arrays of Java Strings. The SOAP message that is being generated by the client seems to use SOAP encoding for the arrays, which it shouldn't be. When the server tries to deserialize the encoded object, the deserialization fails.

The error that is thrown is a SAXException with the following message: "SimpleDeserializer encountered a child element, which is NOT expected, in something it was trying to deserialize." The element that it is encountering is the < item > tag around the array elements.

This seems really basic, but I have googled and have not found anything that solves my problem. Please help! I'm stumped.

The Java object that is causing problems:

public final class DocumentBean {
 private String [] vals;
 public DocumentBean() {}
 public DocumentBean(String [] vals) { this.vals = vals; }
 public String [] getVals() { return vals; }
 public void setVals(String [] vals) { this.vals = vals; }
}

My wscompile ant task:

<wscompile
 fork="true"
 keep="false"
 verbose="true"
 base="${tms-build.dir}/classes"
 classpath="${wscompile.classpath}"
 server="true"
 mapping="${tms-build.dir}/jaxrpc-mapping.xml"
 features="rpcliteral,wsi"
 config="${tms-resources.dir}/tws/config.xml">
 <classpath>
 <path refid="wscompile.classpath" />
 </classpath>
</wscompile>

The WSDL:

 <schema targetNamespace="http://document.tws.mycompany.com"
 xmlns:tns="http://document.tws.mycompany.com"
 xmlns:soap11-enc="http://schemas.xmlsoap.org/soap/encoding/"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/"
 xmlns="http://www.w3.org/2001/XMLSchema">
 <import namespace="http://document.enterprise.mycompany.com"/>
 <import namespace="http://tws.mycompany.com/types"/>
 <complexType name="DocumentBean">
 <sequence>
 <element name="vals" type="string" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
 </sequence>
 </complexType>
 </schema>

The JAX-RPC mapping:

<java-type>com.mycompany.tws.document.DocumentBean</java-type>
<root-type-qname xmlns:typeNS="http://document.tws.mycompany.com">typeNS:DocumentBean</root-type-qname>
<qname-scope>complexType</qname-scope>
<variable-mapping>
<java-variable-name>vals</java-variable-name>
<xml-element-name>vals</xml-element-name>
</variable-mapping>
</java-xml-type-mapping>

The SOAP message generated by the client:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"
 xmlns:xsd="http://www.w3.org/2001/XMLSchema"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
 <soapenv:Body>
 <storeDocument xmlns="http://tws.mycompany.com">
 <DocumentBean_1 xmlns="">
 <vals><item>phoebe</item></vals>
 </DocumentBean_1>
 </storeDocument>
 </soapenv:Body>
</soapenv:Envelope>

The stack trace on the server when the deserialization fails:

2005-11-19 15:08:10,651 DEBUG [org.jboss.axis.encoding.ser.BeanDeserializer] onStartChild: vals
2005-11-19 15:08:10,651 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Enter:getDeserializer: [class=class [Ljava.lang.String;,xmlType={http://schemas.xmlsoap.org/soap/encoding/}Array]
2005-11-19 15:08:10,651 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Exit:getDeserializer: null
2005-11-19 15:08:10,651 DEBUG [org.jboss.axis.encoding.ser.BeanDeserializer] Using itemXmlType = {http://www.w3.org/2001/XMLSchema}string
2005-11-19 15:08:10,651 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Enter:getDeserializer: [class=class java.lang.String,xmlType={http://www.w3.org/2001/XMLSchema}string]
2005-11-19 15:08:10,651 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Exit:getDeserializer: org.jboss.axis.encoding.ser.SimpleDeserializer@15a9173
2005-11-19 15:08:10,661 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Pushing handler org.jboss.axis.encoding.ser.SimpleDeserializer@15a9173
2005-11-19 15:08:10,661 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Exit: DeserializationContextImpl::startElement()
2005-11-19 15:08:10,661 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Enter: DeserializationContextImpl::startElement(, item)
2005-11-19 15:08:10,661 ERROR [org.jboss.axis.providers.java.RPCInvocation] org.xml.sax.SAXException: SimpleDeserializer encountered a child element, which is NOT expected, in something it was trying to deserialize.
org.xml.sax.SAXException: SimpleDeserializer encountered a child element, which is NOT expected, in something it was trying to deserialize.

[bogsolomon]

You are using RPC/encoded it looks like

xmlns:soap11-enc="http://schemas.xmlsoap.org/soap/encoding/"

which is strange since you are using rpc/literal in your wscompile.

Anyway the main problem is that your vals tag contains item tag. Item is not specified anywhere in your wsdl or mapping. Please look at the wiki for an example of how to serialize arrays.

Your message should look something like

 <storeDocument xmlns="http://tws.mycompany.com">
 <DocumentBean_1 xmlns="">
 <vals>phoebe</vals>
 </DocumentBean_1>
 </storeDocument>
 </soapenv:Body>

[thomas.diesler]

client seems to use SOAP encoding arrays

AKAICS, the client is not using soap encoding. That the message does not conform to the wsdl contained schema is probably a bug.

Can you show us the service endpoint interface (SEI)?

[jpowerwa]

Argh. I thought I replied to this weeks ago. Trying again, as I still need help to get away from using RPC/encoded and use RPC/literal instead.

Service Endpoint interface:

package com.mycompany.tws;

import java.rmi.Remote;
import java.rmi.RemoteException;
import com.mycompany.enterprise.document.DocumentAccessException;
import com.mycompany.tws.document.DocumentBean;

public interface DocumentJse extends Remote {
 public String storeDocument(DocumentBean docBean) throws RemoteException, DocumentAccessException;
}

Service endpoint implementation:

package com.mycompany.tws;

import java.rmi.RemoteException;
import javax.xml.rpc.ServiceException;
import javax.xml.rpc.server.ServiceLifecycle;
import com.mycompany.enterprise.document.DocumentAccessException;
import com.mycompany.tws.document.DocumentBean;

public class DocumentJseImpl implements DocumentJse, ServiceLifecycle {

 private static final boolean FORCE_EXCEPTION = false;

 public DocumentJseImpl() {}
 public void init(Object arg0) throws ServiceException {}
 public void destroy() {}

 public String storeDocument(DocumentBean docBean) throws RemoteException, DocumentAccessException {
 System.out.println("DocumentJseImpl.storeDocument");
 if (FORCE_EXCEPTION) {
 System.out.println(" Throwing access exception.");
 throw new DocumentAccessException();
 }
 String[] docVals = docBean.getVals();
 for (int i=0; i<docVals.length; i++) {
 System.out.println(" docVals[" + i + "] = " + docVals);
 }
 return "Happy day.";
 }
 }

DocumentBean transport object:

package com.mycompany.tws.document;

public final class DocumentBean {
 private String [] vals;
 public DocumentBean() {}
 public DocumentBean(String [] vals) { this.vals = vals; }
 public String [] getVals() { return vals; }
 public void setVals(String [] vals) { this.vals = vals; }
}

On the client side, we're doing things a bit strange with regard to registering serializers for the transport objects. I know there is a JBoss specific implementation of ServiceFactory that takes a pointer to the JAX-RPC mapping file so that you don't have to manually register all the bean serializers and deserializers, but we need this client to work with web services deployed on WebLogic as well as on JBoss. Here's the code on the client-side ServiceLocator:

package com.mycompany.twsc;

import java.net.MalformedURLException;
import java.net.URL;
import java.rmi.Remote;
import javax.xml.namespace.QName;
import javax.xml.rpc.Service;
import javax.xml.rpc.ServiceException;
import javax.xml.rpc.ServiceFactory;
import javax.xml.rpc.encoding.TypeMapping;
import javax.xml.rpc.encoding.TypeMappingRegistry;
import org.apache.axis.encoding.ser.BeanDeserializerFactory;
import org.apache.axis.encoding.ser.BeanSerializerFactory;
import com.mycompany.enterprise.ServiceUnavailableException;
import com.mycompany.tws.DocumentJse;
import com.mycompany.tws.document.DocumentBean;

public final class ServiceLocator {

 private static final String DOCUMENT_WSDL_URL =
 "http://localhost:8080/wstesting/document?WSDL";
 private static final String TWS_NS =
 "http://tws.mycompany.com";
 private static final String TWS_DOCUMENT_NS =
 "http://document.tws.mycompany.com";
 private static final QName TWS_SERVICE_QNAME =
 new QName(TWS_NS, "Tws");
 private static final QName DOCUMENT_JSE_PORT_QNAME =
 new QName(TWS_NS, "DocumentJsePort");

 /** The one and only instance of the locator. */
 private static final ServiceLocator INSTANCE = new ServiceLocator();

 /** A cached reference to the service factory. */
 private final ServiceFactory m_serviceFactory;

 // Override default constructor for non-instantiability.
 private ServiceLocator() {
 try {
 m_serviceFactory = ServiceFactory.newInstance();
 } catch (ServiceException se) {
 throw new RuntimeException(se);
 }
 }

 public static ServiceLocator getInstance() {return INSTANCE;}

 private void registerType(
 TypeMapping mapping,
 String nameSpace,
 String localName,
 Class type) {
 QName qn = new QName(nameSpace, localName);
 mapping.register (
 type,
 qn,
 new BeanSerializerFactory(type, qn),
 new BeanDeserializerFactory(type, qn)
 );
 }

 /**
 * Handles the common mechanics and exception handling involved with
 * fetching a service port.
 * @param service the service
 * @param qn the qualified name of the service port
 * @param jse the class of the JSE interface to be fetched
 * @return a remote reference to the service port.
 */
 private Remote getServicePort(Service service, QName qn, Class jse) {

 try {
 return service.getPort(qn, jse);
 } catch (ServiceException se) {
 // TODO log the exception?
 System.out.println(se.getMessage());
 se.printStackTrace();
 return null;
 }

 }

 /**
 * Handles the common mechanics and exception handling involved with
 * fetching a service endpoint.
 * @param wsdlUrl the URL of the WSDL for the service endpoint.
 * @param srvcName the qualifed name of the service endpoint.
 * @return a remote reference to the service.
 */
 private Service getService(String wsdlUrl, QName srvcName)
 throws ServiceUnavailableException {

 Service srvc = null;
 try {
 srvc = m_serviceFactory.createService(new URL(wsdlUrl), srvcName);
 } catch (MalformedURLException mue) {
 System.out.println(mue.getMessage());
 mue.printStackTrace();
 return null;
 } catch (ServiceException se) {
 throw new ServiceUnavailableException(
 "Service " + srvcName.toString() + " is unavailable.", se);
 }
 return srvc;
 }

 /**
 * Looks up the document service and returns a remote reference to it.
 * Also, configures type mappings with serializers and deserializers for
 * each complex type passed to the service
 * API, or returned from it.
 * @return a remote reference to the document service.
 * @throws ServiceUnavailableException if connection cannot be made to svc
 */
 public DocumentJse getDocumentService() throws ServiceUnavailableException {

 DocumentJse docJse = null;
 Service docService = getService(DOCUMENT_WSDL_URL, TWS_SERVICE_QNAME);
 if (docService != null) {
 TypeMapping mapping = getTypeMapping(docService);
 registerType(mapping, TWS_DOCUMENT_NS,
 "DocumentBean", DocumentBean.class);
 docJse = (DocumentJse) getServicePort(docService,
 DOCUMENT_JSE_PORT_QNAME, DocumentJse.class);
 }
 return docJse;
 }

 private TypeMapping getTypeMapping(Service svc) {
 TypeMappingRegistry reg = svc.getTypeMappingRegistry();
 // For rpc/encoded...
// return reg.getTypeMapping(reg.getRegisteredEncodingStyleURIs()[0]);
 // For rpc/literal...
 return reg.getDefaultTypeMapping();
 }
}

client-side interface:

package com.mycompany.tmsc;

import com.mycompany.enterprise.document.DocumentAccessException;

public interface TmsDocumentServices {
 public String storeDocument() throws DocumentAccessException;
}

client-side implementation:

package com.mycompany.twsc;

import java.rmi.RemoteException;
import com.mycompany.enterprise.ServiceUnavailableException;
import com.mycompany.enterprise.document.DocumentAccessException;
import com.mycompany.tmsc.TmsDocumentServices;
import com.mycompany.tws.DocumentJse;
import com.mycompany.tws.document.DocumentBean;

public class TmsDocumentServicesImpl implements TmsDocumentServices {

 private DocumentJse m_documentService;

 public TmsDocumentServicesImpl() throws ServiceUnavailableException {
 m_documentService = ServiceLocator.getInstance().getDocumentService();
 }

 public String storeDocument() throws DocumentAccessException {
 String retval = null;

 DocumentBean docBean = new DocumentBean();
 docBean.setVals(new String[] { "phoebe" });

 try {
 retval = m_documentService.storeDocument(docBean);
 } catch (RemoteException re) {
 throw new RuntimeException(re);
 }
 return retval;
 }
}

TestApp:

package com.mycompany.twsc;

import com.mycompany.enterprise.ServiceUnavailableException;
import com.mycompany.enterprise.document.DocumentAccessException;
import com.mycompany.tmsc.TmsDocumentServices;

public final class TestApp {

 private static TmsDocumentServices m_docSvc;

 public static void main(String[] args) {
 System.out.println("[INFO] Running TestApp.");
 try {
 m_docSvc = new TmsDocumentServicesImpl();
 } catch (ServiceUnavailableException e) {
 System.out.println("[ERROR] Document service is unavailable.");
 return;
 }

 System.out.println("[INFO] Calling storeDocument...");
 String retval = null;
 try {
 retval = m_docSvc.storeDocument();
 } catch (DocumentAccessException e) {
 System.out.println("[ERROR] Caught DocumentAccessException.");
 }
 System.out.println("[INFO] Back from storeDocument. Returned value = " + retval);
 }

}

SOAP message:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<soapenv:Body>
<storeDocument xmlns="http://tws.mycompany.com">
<DocumentBean_1 xmlns="">
<vals><item>phoebe</item></vals>
</DocumentBean_1>
</storeDocument>
</soapenv:Body>
</soapenv:Envelope>

Server error message:

2005-12-02 13:07:41,073 DEBUG [org.jboss.axis.providers.java.RPCInvocation] There are 1 body elements.
2005-12-02 13:07:41,073 DEBUG [org.jboss.axis.providers.java.RPCInvocation] body is org.jboss.axis.message.RPCElement@1afebc9[[storeDocument: null]]
2005-12-02 13:07:41,073 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Pushing handler org.jboss.axis.message.EnvelopeHandler@c80825
2005-12-02 13:07:41,073 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Enter: DeserializationContextImpl::startPrefixMapping(, http://tws.mycompany.com)
2005-12-02 13:07:41,073 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Exit: DeserializationContextImpl::startPrefixMapping()
2005-12-02 13:07:41,073 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Enter: DeserializationContextImpl::startElement(http://tws.mycompany.com, storeDocument)
2005-12-02 13:07:41,073 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Pushing handler org.jboss.axis.message.RPCHandler@8ee5c0
2005-12-02 13:07:41,073 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Exit: DeserializationContextImpl::startElement()
2005-12-02 13:07:41,073 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Enter: DeserializationContextImpl::startElement(, DocumentBean_1)
2005-12-02 13:07:41,073 DEBUG [org.jboss.axis.message.RPCHandler] Enter: RPCHandler.onStartChild()
2005-12-02 13:07:41,073 DEBUG [org.jboss.axis.message.RPCHandler] Type from attributes is: null
2005-12-02 13:07:41,073 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Enter:getDeserializer: [class=class com.mycompany.tws.document.DocumentBean,xmlType={http://document.tws.mycompany.com}DocumentBean]
2005-12-02 13:07:41,083 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Exit:getDeserializer: org.jboss.webservice.encoding.ser.MetaDataBeanDeserializer@faaa93
2005-12-02 13:07:41,083 DEBUG [org.jboss.axis.message.RPCHandler] Exit: RPCHandler.onStartChild()
2005-12-02 13:07:41,083 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Pushing handler org.jboss.webservice.encoding.ser.MetaDataBeanDeserializer@faaa93
2005-12-02 13:07:41,083 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Exit: DeserializationContextImpl::startElement()
2005-12-02 13:07:41,083 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Enter: DeserializationContextImpl::startElement(, vals)
2005-12-02 13:07:41,083 DEBUG [org.jboss.axis.encoding.ser.BeanDeserializer] onStartChild: vals
2005-12-02 13:07:41,083 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Enter:getDeserializer: [class=class [Ljava.lang.String;,xmlType={http://schemas.xmlsoap.org/soap/encoding/}Array]
2005-12-02 13:07:41,083 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Exit:getDeserializer: null
2005-12-02 13:07:41,083 DEBUG [org.jboss.axis.encoding.ser.BeanDeserializer] Using itemXmlType = {http://www.w3.org/2001/XMLSchema}string
2005-12-02 13:07:41,083 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Enter:getDeserializer: [class=class java.lang.String,xmlType={http://www.w3.org/2001/XMLSchema}string]
2005-12-02 13:07:41,103 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Exit:getDeserializer: org.jboss.axis.encoding.ser.SimpleDeserializer@17a82f1
2005-12-02 13:07:41,103 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Pushing handler org.jboss.axis.encoding.ser.SimpleDeserializer@17a82f1
2005-12-02 13:07:41,103 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Exit: DeserializationContextImpl::startElement()
2005-12-02 13:07:41,103 DEBUG [org.jboss.axis.encoding.DeserializationContextImpl] Enter: DeserializationContextImpl::startElement(, item)
2005-12-02 13:07:41,103 ERROR [org.jboss.axis.providers.java.RPCInvocation] org.xml.sax.SAXException: SimpleDeserializer encountered a child element, which is NOT expected, in something it was trying to deserialize.
org.xml.sax.SAXException: SimpleDeserializer encountered a child element, which is NOT expected, in something it was trying to deserialize.
 at org.jboss.axis.encoding.ser.SimpleDeserializer.onStartChild(SimpleDeserializer.java:206)
 at org.jboss.axis.encoding.DeserializationContextImpl.startElement(DeserializationContextImpl.java:1168)
 at org.jboss.axis.message.SAX2EventRecorder.replay(SAX2EventRecorder.java:244)
 at org.jboss.axis.message.SOAPElementAxisImpl.publishToHandler(SOAPElementAxisImpl.java:1386)
 at org.jboss.axis.message.RPCElement.deserialize(RPCElement.java:262)
 at org.jboss.axis.message.RPCElement.getParams(RPCElement.java:396)
 at org.jboss.axis.providers.java.RPCInvocation.prepareFromRequestEnvelope(RPCInvocation.java:235)
 at org.jboss.axis.providers.java.RPCProvider.processMessage(RPCProvider.java:103)
 at org.jboss.axis.providers.java.JavaProvider.invoke(JavaProvider.java:358)
 at org.jboss.axis.strategies.InvocationStrategy.visit(InvocationStrategy.java:73)
 at org.jboss.axis.SimpleChain.doVisiting(SimpleChain.java:160)
 at org.jboss.axis.SimpleChain.invoke(SimpleChain.java:123)
 at org.jboss.axis.handlers.soap.SOAPService.invoke(SOAPService.java:560)
 at org.jboss.webservice.server.ServerEngine.invokeInternal(ServerEngine.java:200)
 at org.jboss.webservice.server.ServerEngine.invoke(ServerEngine.java:89)
 at org.jboss.axis.transport.http.AxisServlet.doPost(AxisServlet.java:905)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
 at org.jboss.axis.transport.http.AxisServletBase.service(AxisServletBase.java:370)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
 at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:81)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
 at org.jboss.web.tomcat.security.CustomPrincipalValve.invoke(CustomPrincipalValve.java:39)
 at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:153)
 at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:59)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
 at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:856)
 at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:744)
 at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
 at org.apache.tomcat.util.net.MasterSlaveWorkerThread.run(MasterSlaveWorkerThread.java:112)
 at java.lang.Thread.run(Thread.java:534)

[thomas.diesler]

According to the schmema your message should look simmilar to this. The item element is in deed incorrect. What is producing this message?

 <DocumentBean_1>
 <vals>phoebe</vals>
 </DocumentBean_1>

Have you looked at

http://wiki.jboss.org/wiki/Wiki.jsp?page=WSArrayTypeMapping