Very Strange Error with Mapping. Please help

[alice azevedo]

Hi!

I'm getting a really strange error with Struts.

My application runs under jBoss and I'm using Hibernate, Struts and SpringFramework.

Turns that when I try to save an object (not anyone, a specific one) the mapping does no occur and when the page expires, I get this error:

21:24:35,929 INFO [SessionFactoryImpl] closing
21:24:36,090 ERROR [[action]] Servlet.service() for servlet action threw exception
java.lang.NullPointerException
at org.apache.struts.action.RequestProcessor.getInternal(RequestProcessor.java:1106)
at org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:516)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
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:159)
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:595)


I tried changing the struts-config mapping, but result in nothing.

Can anybody help me?

Thank you!

[alice azevedo]

To help I'm posting my struts-config with the mapping that fails:

<action path="/saveEvent" name="eventForm" scope="request"
type="actions.EventAction" parameter="save">
<forward name="success" path="/inicial.do"/>
<forward name="error" path="message?showMessage=error">
</action>

The DAO class:
public class EventDAOImpl extends HibernateDaoSupport implements EventDAO
{
public void save(Event event)
{
getHibernateTemplate().saveOrUpdate(event);
}

}


Well the page expires after I call the method to save the Event object at my action class:

public ActionForward save(ActionMapping mapping, ActionForm form, HttpServletRequest req, HttpServletResponse resp) throws ParseException
{
Event event = (Event) req.getSession().getAttribute("event");

if (event == null)
return mapping.findForward("error");


EventDAO eventDao = (EventDAO) getWebApplicationContext().getBean(Constants.EVENT_DAO);
eventDao.save(event);

return mapping.findForward(Constants.MAPPING_SUCCESS);
}


When I'm debuging, when the save is made, I dont know why, the thread doesnt ge to the return line. So when the page expires the exception is thrown.

Please, anybody can help me?

[Brent Sterling]

This sure sounds like it is an issue in your Hibernate layer. I do not have any Hibernate experience, so I cannot help much there. Have you tried setting a break point in your save method? What if you surrounded your call to saveOrUpdate with a "try / catch(Throwable t)" block to see if Hibernate is throwing a meaningful exception. Is Hibernate throwing the NullPointerException?

I am not sure what you mean when you say "the mapping does no(t) occur" and "the page expires".

- Brent

[alice azevedo]

Hi Brent.
Thanks for replying.

I tried to set a breakpoint in the save method. The object is saved normally.
And even with the try/catch, no throwable object is thrown.

What I meant with "the mapping does not occur" is that the hibernate save method is done,
and the next line is the struts mapping return but the thread does not get there, and the
page gets no answer, so when the page expires, that exception is thrown.

I hope I was clear.

Thanks!

[Brent Sterling]

No real ideas. I don't have experience with Spring. Does the call to getBean directly instantiate your bean class, or does Spring create a wrapper around your class?

Have you tried downloading the Struts source code for the version you are using and looking at line 1106 in RequestProcessor.java? Are you using log4j? A couple times I have tracked down tricky Struts issues by cranking the logging level to debug. I don't remember the exact log4j.properties entry...something like this:

log4j.logger.org.apache.struts=DEBUG

- Brent

[alice azevedo]

Hi Brent!

One thing that really looks strange to me, is that I have similar daos and actions that do the same that I'm trying to do with this particular [Event] object.

I have downloaded the struts source code and it wasnt helpful.

I'll take your advice on log4j and struts.

Thanks for the help!

- Alice

[alice azevedo]

Some news!

Seems that something is wrong with the database!
I got the exception: Pool not open

I'm not sure about what it means.
I'm using MySQL.

Can someone help me with that?

Thanks!