Allora... ho usato il debugger, come mi hai detto tu. Ho messo il breackpoint alla riga 20:
codice:
Query q = em.createQuery("SELECT u.username " +
ma quando sono andato all'istruzione successiva premendo F8, è saltato direttamente alla riga 39, cioè all'interno del catch:
codice:
throw new EJBException(e.getMessage());
Questo vuol dire che già alla prima query c'è un errore!!??
Qui c'è il contenuto di Debugger Console:
codice:
Attaching to localhost:9009
LineBreakpoint StreetSoccerBean.java : 20 successfully submitted.
User program running
Breakpoint hit at line 20 in class my.streetsoccer.StreetSoccerBean by thread httpSSLWorkerThread-9090-1.
Thread httpSSLWorkerThread-9090-1 stopped at StreetSoccerBean.java:20.
User program running
Thread httpSSLWorkerThread-9090-1 stopped at StreetSoccerBean.java:39.
User program running
Thread httpSSLWorkerThread-9090-1 stopped.
Mentre questo credo che sia il Server Log di Glassfish:
codice:
javax.ejb.EJBException: nested exception is: java.rmi.ServerException: RemoteException occurred in server thread; nested exception is: 
        java.rmi.RemoteException: An exception occured while creating a query in EntityManager
        at my.streetsoccer._StreetSoccerRemote_Wrapper.registraUtente(my/streetsoccer/_StreetSoccerRemote_Wrapper.java)
        at my.streetsoccer.StreetSoccerServlet.processRequest(StreetSoccerServlet.java:41)
        at my.streetsoccer.StreetSoccerServlet.doPost(StreetSoccerServlet.java:26)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:738)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:831)
        at org.apache.catalina.core.ApplicationFilterChain.servletService(ApplicationFilterChain.java:411)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:317)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:198)
        at org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:390)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:198)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:288)
        at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:271)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:202)
        at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:632)
        at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:577)
        at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:94)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:206)
        at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:632)
        at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:577)
        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:571)
        at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:1080)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:150)
        at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:632)
        at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:577)
        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:571)
        at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:1080)
        at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:272)
        at com.sun.enterprise.web.connector.grizzly.DefaultProcessorTask.invokeAdapter(DefaultProcessorTask.java:637)
        at com.sun.enterprise.web.connector.grizzly.DefaultProcessorTask.doProcess(DefaultProcessorTask.java:568)
        at com.sun.enterprise.web.connector.grizzly.DefaultProcessorTask.process(DefaultProcessorTask.java:813)
        at com.sun.enterprise.web.connector.grizzly.DefaultReadTask.executeProcessorTask(DefaultReadTask.java:341)
        at com.sun.enterprise.web.connector.grizzly.DefaultReadTask.doTask(DefaultReadTask.java:263)
        at com.sun.enterprise.web.connector.grizzly.DefaultReadTask.doTask(DefaultReadTask.java:214)
        at com.sun.enterprise.web.connector.grizzly.TaskBase.run(TaskBase.java:265)
        at com.sun.enterprise.web.connector.grizzly.ssl.SSLWorkerThread.run(SSLWorkerThread.java:106)
Vuol dire che l'errore sta nella sintassi della query? Io non vedo quale possa essere!

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