Problem updating payload

Question

Hi
I am having trouble updating the payload of a task. Whatever I try, I get an exception saying that the parent 'task' node is read-only and so the 'payload' child node can't be updated. I have attached a sample stack trace (edited slightly for legibility).
I have tried all kinds of solutions - cloning nodes, importing nodes, using the multifarious DOMUtil(s) classes that are hanging around to do this and do that, but if the message is correct, then it all seems hopeless.
How does the task node get set to modifiable? Presumably it should get versioned internally by bpel pm and the updates made to the new copy, but that is clearly not something I should be worrying about as an application developer. Is there a timing problem with the versioning - trying to update before the new version is created? (I am calling IWorklistTask.setPayload followed by IWorklistService.updateTask(context, task), although obviously the code never gets as far as updateTask).
Is there another method I should be using instead of IWorklistTask.setPayload? Or something else to call beforehand?
Any help would be appreciated because this is really frustrating :<)
Best wishes
John Prince
org.w3c.dom.DOMException: Modification is not allowed on the w3c dom node
     "<task xmlns="http://xmlns.oracle.com/pcbpel/taskservice/task">
     <taskId>18a858bbe1d2345b:737371:10320abfe2b:-7fb1</taskId>
     <title>Confirm Address Change</title>
     <acquiredBy>john.prince</acquiredBy>
     <owner>bpeladmin</owner>
     <conclusion/><state>ASSIGNED</state><subState>ACQUIRED</subState>
     <processId>HomeAddressChange</processId><processName>HomeAddressChange</processName><taskGroupId/>
     <taskType>http://PC-05-008:9700/orabpel/default/HomeAddressChange/1.0/taskConfigSimpleWorkflow1.xml</taskType>
     <identificationKey/><priority>3</priority><creator>bpeladmin</creator><updatedBy>john.prince</updatedBy>
     <processVersion>1.0</processVersion><instanceId>1113</instanceId><domainId>default</domainId>
     <payload><PersonChangeRequest xmlns="http://bedag.ch/pef/prototype" targetPN="500000" userPN="111111">
          <address><zusatz/><strasse>Scheibenstrasse 19</strasse><plz>3014</plz><ort>Bern</ort></address></PersonChangeRequest>
     </payload>
     </task>"
because of its root element "task" state is "READ-ONLY". Please consult the documentation for a list of all the permissible operations that can be performed on a dom node when it in the "READ-ONLY" state.
     at com.collaxa.cube.xml.dom.CubeDOMElement.checkIfCanModify(CubeDOMElement.java:1695)
     at com.collaxa.cube.xml.dom.CubeDOMElement.markAsDirty(CubeDOMElement.java:1581)
     at com.collaxa.cube.xml.dom.CubeDOMElement.removeNode(CubeDOMElement.java:472)
     at org.collaxa.thirdparty.dom4j.tree.AbstractElement.remove(AbstractElement.java:1454)
     at org.collaxa.thirdparty.dom4j.tree.AbstractElement.remove(AbstractElement.java:1353)
     at org.collaxa.thirdparty.dom4j.tree.AbstractNode.detach(AbstractNode.java:114)
     at com.collaxa.cube.xml.BaseFacade.removeChildElement(BaseFacade.java:530)
     at oracle.tip.pc.services.hw.task.impl.Task.setPayload(Task.java:1523)
     at oracle.tip.pc.services.hw.worklist.WorklistTask.setPayload(WorklistTask.java:1742)
     at ch.bedag.pef.prototype.iflow.utils.bpel.WorklistUtils.updatePayload(WorklistUtils.java:36)
     at ch.bedag.pef.prototype.iflow.web.pages.Address.changeAddress(Address.java:105)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
     at java.lang.reflect.Method.invoke(Method.java:324)
     at org.apache.tapestry.listener.ListenerMap.invokeTargetMethod(ListenerMap.java:257)
     at org.apache.tapestry.listener.ListenerMap.access$100(ListenerMap.java:46)
     at org.apache.tapestry.listener.ListenerMap$SyntheticListener.invoke(ListenerMap.java:97)
     at org.apache.tapestry.listener.ListenerMap$SyntheticListener.actionTriggered(ListenerMap.java:102)
     at org.apache.tapestry.form.Form.renderComponent(Form.java:423)
     at org.apache.tapestry.AbstractComponent.render(AbstractComponent.java:857)
     at org.apache.tapestry.form.Form.rewind(Form.java:568)
     at org.apache.tapestry.engine.RequestCycle.rewindForm(RequestCycle.java:432)
     at org.apache.tapestry.form.Form.trigger(Form.java:582)
     at org.apache.tapestry.engine.DirectService.service(DirectService.java:169)
     at org.apache.tapestry.engine.AbstractEngine.service(AbstractEngine.java:872)
     at org.apache.tapestry.ApplicationServlet.doService(ApplicationServlet.java:197)
     at org.apache.tapestry.ApplicationServlet.doPost(ApplicationServlet.java:326)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
     at com.evermind.server.http.ResourceFilterChain.doFilter(ResourceFilterChain.java:65)
     at org.apache.tapestry.RedirectFilter.doFilter(RedirectFilter.java:106)
     at com.evermind.server.http.ServletRequestDispatcher.invoke(ServletRequestDispatcher.java:649)
     at com.evermind.server.http.ServletRequestDispatcher.forwardInternal(ServletRequestDispatcher.java:322)
     at com.evermind.server.http.HttpRequestHandler.processRequest(HttpRequestHandler.java:790)
     at com.evermind.server.http.HttpRequestHandler.run(HttpRequestHandler.java:270)
     at com.evermind.server.http.HttpRequestHandler.run(HttpRequestHandler.java:112)
     at com.evermind.util.ReleasableResourcePooledExecutor$MyWorker.run(ReleasableResourcePooledExecutor.java:192)
     at java.lang.Thread.run(Thread.java:534)

Answer 1

Hi
I found the problem - as far as I can tell, acquireTask returns an immutable IWorklistTask. When I called getWorklistTaskDetails, it returned a mutable version.
If this is intentional, you might want to add it to the docs, because is it a bit confusing.
Best wishes
John