simple workflow deploy causes NullPointer

[fence]

environment
    amazon ec2 linux
    mysql 5.5
    activiti 5.14

I create a workflow in activiti explorer with just a named start node.  When I deploy I then start seeing these errors in the Tomcat logs:

09:05:36,592 [http-bio-8080-exec-10] INFO  org.activiti.engine.impl.bpmn.deployer.BpmnDeployer  - Processing resource mark square.bpmn20.xml
Feb 26, 2014 9:05:39 PM com.vaadin.Application terminalError
SEVERE: Terminal error:
com.vaadin.event.ListenerMethod$MethodException: Invocation of method buttonClick in org.activiti.explorer.ui.mainlayout.MainMenuBar$ShowProcessDefinitionsClickListener failed.
   at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:530)
   at com.vaadin.event.EventRouter.fireEvent(EventRouter.java:164)
   at com.vaadin.ui.AbstractComponent.fireEvent(AbstractComponent.java:1219)
   at com.vaadin.ui.Button.fireClick(Button.java:567)
   at com.vaadin.ui.Button.changeVariables(Button.java:223)
   at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.changeVariables(AbstractCommunicationManager.java:1460)
   at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.handleVariableBurst(AbstractCommunicationManager.java:1404)
   at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.handleVariables(AbstractCommunicationManager.java:1329)
   at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.doHandleUidlRequest(AbstractCommunicationManager.java:761)
   at com.vaadin.terminal.gwt.server.CommunicationManager.handleUidlRequest(CommunicationManager.java:325)
   at com.vaadin.terminal.gwt.server.AbstractApplicationServlet.service(AbstractApplicationServlet.java:501)
   at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
   at org.activiti.explorer.filter.ExplorerFilter.doFilter(ExplorerFilter.java:44)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
   at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
   at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
   at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
   at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
   at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
   at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
   at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
   at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
   at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
   at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
   at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1146)
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
   at java.lang.Thread.run(Thread.java:701)
Caused by: java.lang.NullPointerException
   at org.activiti.explorer.ui.mainlayout.MainMenuBar.setMainNavigation(MainMenuBar.java:68)
   at org.activiti.explorer.ui.mainlayout.MainLayout.setMainNavigation(MainLayout.java:67)
   at org.activiti.explorer.ui.MainWindow.setMainNavigation(MainWindow.java:83)
   at org.activiti.explorer.DefaultViewManager.switchView(DefaultViewManager.java:341)
   at org.activiti.explorer.DefaultViewManager.showDeployedProcessDefinitionPage(DefaultViewManager.java:206)
   at org.activiti.explorer.ui.mainlayout.MainMenuBar$ShowProcessDefinitionsClickListener.buttonClick(MainMenuBar.java:201)
   at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
   at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
   at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
   at java.lang.reflect.Method.invoke(Method.java:622)
   at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:510)
   … 30 more

[fence]

If I logout and log back in I'm able to continue working with Activiti Explorer

[trademak]

That's not a valid process definition. You have to create a sound process definition with a start event, a task and an end event.

Best regards,

[seema]

I Have problem something like you define above. How you solved it??

[rima]

I was running the activiti-webapp-explorer2 web app.  I am facing a similar issue. I had created a proper process with a start event, task and a end event. Deployment was successful from the explorer. But after deployment it redirects me to a page where none of the links work. But again if u restart the server and login again, the links work.

stacktrace:
com.vaadin.Application terminalError
SEVERE: Terminal error:
com.vaadin.event.ListenerMethod$MethodException: Invocation of method buttonClick in org.activiti.explorer.ui.mainlayout.MainMenuBar$ShowProcessDefinitionsClickListener failed.
at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:530)
at com.vaadin.event.EventRouter.fireEvent(EventRouter.java:164)
at com.vaadin.ui.AbstractComponent.fireEvent(AbstractComponent.java:1219)
at com.vaadin.ui.Button.fireClick(Button.java:567)
at com.vaadin.ui.Button.changeVariables(Button.java:223)
at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.changeVariables(AbstractCommunicationManager.java:1460)
at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.handleVariableBurst(AbstractCommunicationManager.java:1404)
at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.handleVariables(AbstractCommunicationManager.java:1329)
at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.doHandleUidlRequest(AbstractCommunicationManager.java:761)
at com.vaadin.terminal.gwt.server.CommunicationManager.handleUidlRequest(CommunicationManager.java:325)
at com.vaadin.terminal.gwt.server.AbstractApplicationServlet.service(AbstractApplicationServlet.java:501)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.activiti.explorer.filter.ExplorerFilter.doFilter(ExplorerFilter.java:53)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2430)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2419)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NullPointerException
at org.activiti.explorer.ui.mainlayout.MainMenuBar.setMainNavigation(MainMenuBar.java:68)
at org.activiti.explorer.ui.mainlayout.MainLayout.setMainNavigation(MainLayout.java:67)
at org.activiti.explorer.ui.MainWindow.setMainNavigation(MainWindow.java:83)
at org.activiti.explorer.DefaultViewManager.switchView(DefaultViewManager.java:346)
at org.activiti.explorer.DefaultViewManager.showDeployedProcessDefinitionPage(DefaultViewManager.java:207)
at org.activiti.explorer.ui.mainlayout.MainMenuBar$ShowProcessDefinitionsClickListener.buttonClick(MainMenuBar.java:201)
at sun.reflect.GeneratedMethodAccessor160.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:510)
… 34 more

[rima]

Found the reason for this error. In activiti explorer, when a admin user logs in and deploys a process. After deployment it is redirected to a Manage processes page, which allows you to see the jobs started or allows you to undeploy a proess etc. This works fine for admin user. But if the user is not admin, then he is should not be allowed to see the Manage page. But still it redirects him to that page.. and i think sine he doesn't have the permission none of the links in the page works and we get this error.
com.vaadin.Application terminalError
SEVERE: Terminal error:
com.vaadin.event.ListenerMethod$MethodException: Invocation of method buttonClick in org.activiti.explorer.ui.mainlayout.MainMenuBar$ShowProcessDefinitionsClickListener failed…