Invoke a FTP "Get File" operation throws java.lang.ClassCastException:

Question

Hi there,
I am working on a very simple sample project that will pull the file from a ftp site. I create a partner link with FTP adpater with "Get File" operation.
When I deploy and run the SIMPLE project, it throws the following exception.
I am wondering if any of you experienced the same problem and how to resolve the issue. Your help will be greatly appreciated.
Here is the error message:
<messages><input><Invoke_1_Get_InputVariable><part xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" name="Root-Element"><Root-Element xmlns="http://TargetNamespace.com/ftp_service"/>
</part></Invoke_1_Get_InputVariable></input><fault><bindingFault xmlns="http://schemas.oracle.com/bpel/extension"><part name="summary"><summary>file:/C:/product/10.1.3.1/OracleAS_1/bpel/domains/default/tmp/.bpel_FTPProcess2_1.0_709914d835a81c407ed668866e080b9e.tmp/ftp_service.wsdl [ Get_ptt::Get(Root-Element) ] - WSIF JCA Execute of operation 'Get' failed due to: Could not instantiate InteractionSpec oracle.tip.adapter.ftp.inbound.FTPActivationSpec due to: oracle.tip.adapter.ftp.inbound.FTPActivationSpec; nested exception is:
     java.lang.ClassCastException: oracle.tip.adapter.ftp.inbound.FTPActivationSpec; nested exception is:
     org.collaxa.thirdparty.apache.wsif.WSIFException: Could not instantiate InteractionSpec oracle.tip.adapter.ftp.inbound.FTPActivationSpec due to: oracle.tip.adapter.ftp.inbound.FTPActivationSpec; nested exception is:
     java.lang.ClassCastException: oracle.tip.adapter.ftp.inbound.FTPActivationSpec</summary>
</part><part name="detail"><detail>org.collaxa.thirdparty.apache.wsif.WSIFException: Could not instantiate InteractionSpec oracle.tip.adapter.ftp.inbound.FTPActivationSpec due to: oracle.tip.adapter.ftp.inbound.FTPActivationSpec; nested exception is:
     java.lang.ClassCastException: oracle.tip.adapter.ftp.inbound.FTPActivationSpec</detail>
</part></bindingFault></fault></messages>

Answer 1

Take a look at the stack trace, it shows you exactly where the error is coming from:
java.lang.ClassCastException: org.theclass.candidate.view.SearchForm
org.theclass.candidate.view.CandidateListAction.execute(CandidateListAction.java:41)Line 41 in your CandidateListAction.
Probably it is failing on a cast of your action form.
Taking a closer look at your struts-config, you are "chaining" actions.
Your AddCandidateAction uses the candidateForm, and forwards to CandidateListAction.do
Your CandidateListAction uses the searchForm.
That will be the cause of your class cast exception.
<action path="/Add"
  name="candidateForm"
  type="org.theclass.candidate.view.AddCandidateAction"
  validate ="true"
  input="/jsp/addcandidate.jsp">
  <forward name="success" path="/CandidateList.do"/>
</action>
<action path="/CandidateList"
type="org.theclass.candidate.view.CandidateListAction"
name="searchForm"
scope="request" >
<forward name="failure" path="/jsp/list.jsp"/>
<forward name="success" path="/jsp/candidatelist.jsp"/>
</action>Check out: http://struts.apache.org/1.x/faqs/newbie.html#chaining
Solutions?
- don't chain actions ;-)
- use the same action form for both actions (possible?)
- make the actionForward a "redirect" one. That means a new request, and losing any request parameters/attributes but should prevent this class cast exception.
Hope this helps,
evnafets