2 Replies Latest reply on Jan 10, 2006 4:14 AM by thomas.diesler

    Problem  using inheritance in Webservice value types

    grp_eee
    grp_eee Jan 4, 2006 4:33 PM

      Hi,

      We are using JBoss 4.0.3 for our webservice implementation.
      We want to expose a generic interface which can take a valuetype or any of its subtypes as parameters.

      My Service Interface looks like this

      public interface PolicyWS extends java.rmi.Remote {
 public Policy createPolicy(Policy policy) throws
 java.rmi.RemoteException;
}


      Here the createPolicy method can take any valuetype of type Policy as its parameter

      Policy and its subclasses looks like this: 

      public abstract class Policy
{
 private String policytype;
 private String name;
.......getters and setters
}

public class AVPolicy extends Policy implements Serializable
{
 private Integer avpolicyid;
.......getters and setters

}


public class BackupPolicy extends Policy implements Serializable
{
 private Integer backuppolicyid;
.......getters and setters

}


      We use extension mechanism in our wsdl to expose this interface

      WSDL looks like: 


      <?xml version="1.0" encoding="UTF-8"?>

<definitions name="PolicyWebservice" targetNamespace="http://sample/prd/r1" xmlns:tns="http://sample/prd/r1" xmlns="http://schemas.xmlsoap.org/wsdl/" xmlns:ns2="http://sample/prd/r1/types" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/">
 <types>
 <schema targetNamespace="http://sample/prd/r1/types" xmlns:tns="http://sample/prd/r1/types" 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">

 <complexType name="createPolicy">
 <sequence>
 <element name="Policy_1" type="tns:Policy" nillable="true"/></sequence></complexType>

 <complexType name="BackupPolicy">
 <complexContent>
 <extension base="tns:Policy">
 <sequence>
 <element name="backuppolicyid" type="int" nillable="true"/>
 </sequence></extension></complexContent></complexType>
 <complexType name="AVPolicy">
 <complexContent>
 <extension base="tns:Policy">
 <sequence>
 <element name="avpolicyid" type="int" nillable="true"/>
 </sequence></extension></complexContent></complexType>

 <complexType name="Policy">
 <sequence>
 <element name="name" type="string" nillable="true"/>
 <element name="policytype" type="string" nillable="true"/></sequence></complexType>
 <complexType name="createPolicyResponse">
 <sequence>
 <element name="result" type="tns:Policy" nillable="true"/></sequence></complexType>
 <element name="createPolicy" type="tns:createPolicy"/>
 <element name="createPolicyResponse" type="tns:createPolicyResponse"/></schema></types>
 <message name="PolicyWS_createPolicy">
 <part name="parameters" element="ns2:createPolicy"/></message>
 <message name="PolicyWS_createPolicyResponse">
 <part name="result" element="ns2:createPolicyResponse"/></message>
 <portType name="PolicyWS">
 <operation name="createPolicy">
 <input message="tns:PolicyWS_createPolicy"/>
 <output message="tns:PolicyWS_createPolicyResponse"/></operation></portType>
 <binding name="PolicyWSBinding" type="tns:PolicyWS">
 <soap:binding transport="http://schemas.xmlsoap.org/soap/http" style="document"/>
 <operation name="createPolicy">
 <soap:operation soapAction=""/>
 <input>
 <soap:body use="literal"/></input>
 <output>
 <soap:body use="literal"/></output></operation></binding>
 <service name="PolicyWebservice">
 <port name="PolicyWSPort" binding="tns:PolicyWSBinding">
 <soap:address location="REPLACE_WITH_ACTUAL_URL"/></port></service></definitions>



      When we try to invoke this service passing a parameter of type BackupPolicy the request works fine( i.e it converts to the proper subtype on the server side). But when i return the BackupPolicy instance , I get a ClassCastException.

      When i had a look at the SOAP request and response, I found that the request is encoded with the value type whereas the response is not.That is why the client is unable to instantiate the proper value type.

      SOAP Request XML 

      <?xml version="1.0" encoding="UTF-8"?>
<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>
 <createPolicy xmlns="http://sample/prd/r1/types">
 <Policy_1 xsi:type="ns1:BackupPolicy" xmlns:ns1="http://sample/prd/r1/types" xmlns="">
 <name xsi:nil="true"/>
 <policytype>backup</policytype>
 <backuppolicyid>1</backuppolicyid>
 </Policy_1>
 </createPolicy>
 </soapenv:Body>
</soapenv:Envelope>


      SOAP Response XML 

      <?xml version="1.0" encoding="UTF-8"?>
<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>
 <ns1:createPolicyResponse xmlns:ns1="http://sample/prd/r1/types">
 <result>
 <name>backup</name>
 <policytype xsi:nil="1"/>
 <backuppolicyid xsi:nil="1"/>
 </result>
 </ns1:createPolicyResponse>
 </soapenv:Body>
</soapenv:Envelope>

      My client snippet 

      PolicyWebserviceLocator loc = new PolicyWebserviceLocator();
 PolicyWS policyws = loc.getPolicyWSPort();
 BackupPolicy policy = new BackupPolicy();
 policy.setBackuppolicyid(1);
 policy.setPolicytype("backup");
 BackupPolicy bp = (BackupPolicy)policyws.createPolicy(policy); //ClassCastException bp.getBackuppolicyid();



      Is this an issue with JBoss ? Please provide me any pointers on this.

      Thanks in advance
      -Ram





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