How to find out the cause of "Cannot create JDBC driver"?

Question

A small Java web application constantly runs into a problem of "Cannot of create JDBC driver of class 'org.postgresql.Driver' for connect URL 'jdbc:postgresl://localhost:5432/myapp'". The problem still exists after upgrading the driver. After recycling the server, this problem will be resolved. It, however, will come back after a while.
Any suggestions to solve this problem?
Thanks a lot.

Answer 1

jschell wrote:
vwuvancouver wrote:
Any suggestions to solve this problem?To start with get the full and complete stack trace.
However since it is an intermittent problem there are only two possibilities
1. You have some code that is written correctly and some that is not.
2. It is a resource not code usage problem. Such as that you are not closing all result sets, statements and connections.Here is related log messages:
2009-04-30 09:29:21,386  INFO XmlWebApplicationContext:601: - Closing application context [WebApplicationContext for namespace 'mybookmarks-servlet']
2009-04-30 09:29:21,387  INFO DefaultListableBeanFactory:273: - Destroying singletons in {org.springframework.beans.factory.support.DefaultListableBeanFactory defining beans [messageSource,viewResolver,localeResolver,untapedUrlMapping,urlMapping,localeChangeInterceptor,errorsController,myBookmarksController,bookmarkController,reminderController,accountController,userControllerMethodResolver,userFormController,searchFormController,directoryController,directoryControllerMethodResolver,secureHandlerMapping,signonInterceptor,addBookmarkFromListFormController,addBookmarkFormController,bookmarkValidator,editWebSiteEntryFormController,addCommentFormController,reminderFormController,genericReminderFormController,alterReminderDateFormController,contactFormController,invitationFormController,propertyConfigurer,mailSender]; parent: org.springframework.beans.factory.support.DefaultListableBeanFactory defining beans [propertyConfigurer,mailSender,userValidator,bookmarkService,dataSource,sessionFactory,transactionManager,accountDao,categoryDao,webSiteDao,siteVisitDao,reminderDao,commentDao,bookmarkDao]; root of BeanFactory hierarchy}
2009-04-30 09:29:21,388  INFO GenericWebApplicationContext:601: - Closing application context [org.springframework.web.context.support.GenericWebApplicationContext;hashCode=15954072]
2009-04-30 09:29:21,389  INFO DefaultListableBeanFactory:273: - Destroying singletons in {org.springframework.beans.factory.support.DefaultListableBeanFactory defining beans [modelView,addCommentFormView,discoveryFormView,mostVisitedView,bookmarkListView,contactFormView,actionResultView,accountView,reminderFormView,reminderDateFormView,searchList2View,helpView,homeView,taggedListView,searchFormView,reminderListView,webSiteEntryFormView,reminderForm2View,categorizedList2View,invitationFormView,myHomeView,taggedList2View,contactListView,aboutView,bookmarkFormView,bookmarkForm2View,newEntries2View,categorizedListView,signinFormView,accountActionResultView,userFormView,siteActionResultView,searchListView,mostVisited2View,newEntriesView,errorHttp404View]; parent: org.springframework.beans.factory.support.DefaultListableBeanFactory defining beans [messageSource,viewResolver,localeResolver,untapedUrlMapping,urlMapping,localeChangeInterceptor,errorsController,myBookmarksController,bookmarkController,reminderController,accountController,userControllerMethodResolver,userFormController,searchFormController,directoryController,directoryControllerMethodResolver,secureHandlerMapping,signonInterceptor,addBookmarkFromListFormController,addBookmarkFormController,bookmarkValidator,editWebSiteEntryFormController,addCommentFormController,reminderFormController,genericReminderFormController,alterReminderDateFormController,contactFormController,invitationFormController,propertyConfigurer,mailSender]; parent: org.springframework.beans.factory.support.DefaultListableBeanFactory defining beans [propertyConfigurer,mailSender,userValidator,bookmarkService,dataSource,sessionFactory,transactionManager,accountDao,categoryDao,webSiteDao,siteVisitDao,reminderDao,commentDao,bookmarkDao]; root of BeanFactory hierarchy}
2009-04-30 09:29:21,391  INFO GenericWebApplicationContext:601: - Closing application context [org.springframework.web.context.support.GenericWebApplicationContext;hashCode=29369879]
2009-04-30 09:29:21,392  INFO DefaultListableBeanFactory:273: - Destroying singletons in {org.springframework.beans.factory.support.DefaultListableBeanFactory defining beans [modelView,addCommentFormView,discoveryFormView,mostVisitedView,bookmarkListView,contactFormView,accountView,actionResultView,reminderFormView,reminderDateFormView,searchList2View,helpView,homeView,configView,taggedListView,searchFormView,reminderListView,webSiteEntryFormView,reminderForm2View,categorizedList2View,invitationFormView,taggedList2View,myHomeView,contactListView,aboutView,bookmarkFormView,bookmarkForm2View,newEntries2View,categorizedListView,signinFormView,accountActionResultView,userFormView,siteActionResultView,searchListView,mostVisited2View,newEntriesView,errorHttp404View]; parent: org.springframework.beans.factory.support.DefaultListableBeanFactory defining beans [messageSource,viewResolver,localeResolver,untapedUrlMapping,urlMapping,localeChangeInterceptor,errorsController,myBookmarksController,bookmarkController,reminderController,accountController,userControllerMethodResolver,userFormController,searchFormController,directoryController,directoryControllerMethodResolver,secureHandlerMapping,signonInterceptor,addBookmarkFromListFormController,addBookmarkFormController,bookmarkValidator,editWebSiteEntryFormController,addCommentFormController,reminderFormController,genericReminderFormController,alterReminderDateFormController,contactFormController,invitationFormController,propertyConfigurer,mailSender]; parent: org.springframework.beans.factory.support.DefaultListableBeanFactory defining beans [propertyConfigurer,mailSender,userValidator,bookmarkService,dataSource,sessionFactory,transactionManager,accountDao,categoryDao,webSiteDao,siteVisitDao,reminderDao,commentDao,bookmarkDao]; root of BeanFactory hierarchy}
2009-04-30 09:29:21,394  INFO XmlWebApplicationContext:601: - Closing application context [Root WebApplicationContext]
2009-04-30 09:29:21,395  INFO DefaultListableBeanFactory:273: - Destroying singletons in {org.springframework.beans.factory.support.DefaultListableBeanFactory defining beans [propertyConfigurer,mailSender,userValidator,bookmarkService,dataSource,sessionFactory,transactionManager,accountDao,categoryDao,webSiteDao,siteVisitDao,reminderDao,commentDao,bookmarkDao]; root of BeanFactory hierarchy}
2009-04-30 09:29:21,396  INFO LocalSessionFactoryBean:184: - Closing Hibernate SessionFactory
2009-04-30 09:29:21,397  INFO SessionFactoryImpl:767: - closing
2009-04-30 09:29:21,408  WARN JDBCExceptionReporter:71: - SQL Error: 0, SQLState: null
2009-04-30 09:29:21,410 ERROR JDBCExceptionReporter:72: - Cannot create JDBC driver of class 'org.postgresql.Driver' for connect URL 'jdbc:postgresql://localhost:5432/homepage'
2009-04-30 09:29:21,411  WARN JDBCExceptionReporter:71: - SQL Error: 0, SQLState: null
2009-04-30 09:29:21,414 ERROR JDBCExceptionReporter:72: - Cannot create JDBC driver of class 'org.postgresql.Driver' for connect URL 'jdbc:postgresql://localhost:5432/homepage'
...Your analysis seems very reasonable. As the above log messages, this application is built on Hibernate and Spring. All back end is taken care by Hibernate. I don't have a direct control on it. I should ask the Hibernate crowd about this issue. The Hibernate forum is still down at this moment.
Edited by: vwuvancouver on Apr 30, 2009 1:12 PM