Nicholas,
Your PortableRemoteObject.narrow call narrows to EJBHome.class.
Then you call 'create' using reflection. Although it will work
with some products (including Sybase EAServer) this is not portable.
After narrowing to EJBHome.class, you should get the EJB meta data,
and narrow to md.getHomeinterfaceClass().
Nicholas wrote:
> Here is some code from a servlet we wrote that accepts
> the bean name, a method name and an array of objects
> as parameters and invokes against the EJB. It was used
> to access functionality in EJBs through HTTP in lieu
> of IIOP, and I have to say, it was much faster !
>
> public void doPost(HttpServletRequest request,
> HttpServletResponse response) {
> dumpAttributes(request);
> ObjectOutputStream out = null;
> try {
> out = new
> ObjectOutputStream(response.getOutputStream());
> response.setHeader("Content-Type", "no-cache");
> response.setHeader("Pragma", "no-cache");
> response.setHeader("Expires", "Tue, 1 Jan 1980
> 10:00:00 GMT");
> LOG.debug("--------------- EJB Router Request
> v" + version + "--------------");
> response.setContentType("application/java");
> LOG.debug("Opening Input Stream");
> ObjectInputStream ois = new
> ObjectInputStream(request.getInputStream());
> LOG.debug("Requesting Object From Input
> Stream");
> Object obj = ois.readObject();
> LOG.debug("Extracted Object From Input Stream:"
> + obj.getClass().getName());
> LOG.debug("Casting To EJBRouterRequest...");
> EJBRouterRequest ejbRequest =
> (EJBRouterRequest)obj;
> LOG.debug("Cast.");
> LOG.debug("Looking Up Home:" +
> ejbRequest.getBeanName());
> EJBObject remote =
> (EJBObject)remotes.get(ejbRequest.getBeanName());
> Class[] classMethodParams = null;
> Method method = null;
> if(remote==null) {
> obj = ctx.lookup(ejbRequest.getBeanName());
> LOG.debug("Home Looked Up:" +
> obj.getClass().getName());
> LOG.debug("Narrowing to EJBHome....");
> EJBHome home =
> (EJBHome)PortableRemoteObject.narrow(obj,
> EJBHome.class);
> LOG.debug("EJBHome Narrowed.");
> classMethodParams = new Class[0];
> LOG.debug("Creating create() method...");
> method = home.getClass().getMethod("create",
> classMethodParams);
> LOG.debug("create() method created.
> Invoking...");
> remote = (EJBObject) method.invoke(home,
> classMethodParams);
> remotes.put(ejbRequest.getBeanName(), remote);
> LOG.debug("Remote Created.");
> } else {
> LOG.info("Remote Found In Cache:" +
> remote.getClass().getName());
> }
> classMethodParams = new
> Class[ejbRequest.getArgs().length];
> for(int i=0; i < classMethodParams.length; i++)
> {
> classMethodParams[i] =
> ejbRequest.getArgs()[i].getClass();
> }
> LOG.debug("Getting Requested Method.....");
> method =
> remote.getClass().getMethod(ejbRequest.getMethodName(),
> classMethodParams);
> LOG.debug("Got Requested Method:" + method + ".
> Invoking....");
> obj = method.invoke(remote,
> ejbRequest.getArgs());
> LOG.debug("Invoked. Object Is:" +
> obj.getClass().getName());
> LOG.debug("Returning Result...");
> LOG.debug("ObjectValue:" + obj.toString());
> out.writeObject(obj);
> LOG.debug("--------------- END Router Request
> --------------");
> } catch (Throwable erx) {
> if(erx instanceof InvocationTargetException) {
> Throwable thr =
> ((InvocationTargetException)erx).getTargetException();
> LOG.error("EJBRouter Service Invocation
> Exception:" + thr);
> Exception newEx = new Exception("EJBRouter
> Invocation Exception:" + thr.getClass().getName() +
> ":" + thr.getMessage());
> try {
> out.writeObject(newEx);
> } catch (Throwable ioex) {
> LOG.error("EJBRouter Could Not Write
> Exception Object To Output Stream:" + ioex);
> }
> //throw new ServletException(thr);
> } else {
> LOG.error("EJBRouter Service Unknown
> Exception:" + erx);
> Exception newEx = new Exception("EJBRouter
> Invocation Exception:" + erx.getClass().getName() +
> ":" + erx.getMessage());
> try {
> out.writeObject(newEx);
> } catch (Throwable ioex) {
> LOG.error("EJBRouter Could Not Write
> Exception Object To Output Stream:" + ioex);
> }
> //throw new ServletException(erx);
> }
> } finally {
> try { out.flush(); } catch (Exception e) {};
> try { out.close(); } catch (Exception e) {};
> }
> }
>
> //Nicholas
>
> --- Gene Chuang <[EMAIL PROTECTED]> wrote:
>
>>Hi Anthony,
>>
>>You cannot "dynamically cast" in Java (doesn't make
>>sense!), but you CAN dynamically
>>evoke methods using reflection.
>>
>>So, just reflectively evoke "create" on the Object
>>retreived from JNDI to get the
>>EJBObject, and once again reflectively evoke the
>>business method of your choosing on the
>>resulting Object to achieve your goal.
>>
>>Gene
>>--- Catalfano Anthony
>><[EMAIL PROTECTED]> wrote:
>>
>>>I'm writing a diagnostic utility servlet that will
>>>
>>allow our operations
>>
>>>people to enter 3 parameters: PROVIDER_URL,
>>>
>>JNDIHomeName, and BeanName. The
>>
>>>servlet needs to dynamically look up the home,
>>>
>>dynamically cast it to the
>>
>>>JNDIHomeName param, call create() on the Home,
>>>
>>dynamically cast the bean the
>>
>>>the BeanName. Wondering if anyone has code that
>>>
>>will do this.
>>
>>>Thanks
>>>
>>>Anthony Catalfano
>>>Information Technology Analyst
>>>Deere & Company
>>>309-748-5201
>>>
>>>
>>>
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>>
>>
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>>
> ===========================================================================
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>>
>>
>
>
> =====
> Nicholas Whitehead
> Home: (973) 377 9335
> Cell: (973) 615 9646
> Work(@ JP Morgan): (212) 235 5783
> [EMAIL PROTECTED]
>
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