Activiti-explorer runs return error!

[fate-testarossa]

after i deploy the activiti-explorer into tomcat,i startup tomcat and click "http://localhost:8080/activiti-explorer" in IE 11.The user login page is correct,but when  i logged in and click any one of the first three button,which are "tasks,process,diagram",it will return an internal error.And in the tomcat log,it said "
com.vaadin.Application terminalError
严重: Terminal error:
java.lang.NumberFormatException: For input string: "486.9599914550781"
   at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
   at java.lang.Integer.parseInt(Integer.java:492)
   at java.lang.Integer.parseInt(Integer.java:527)
   at com.vaadin.terminal.gwt.client.MouseEventDetails.deSerialize(MouseEventDetails.java:123)
   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:727)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.activiti.explorer.filter.ExplorerFilter.doFilter(ExplorerFilter.java:42)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
   at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
   at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
   at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
   at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
   at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
   at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
   at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
   at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
   at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
   at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
   at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
   at java.lang.Thread.run(Thread.java:745)
二月 11, 2015 3:27:30 下午 com.vaadin.Application terminalError
严重: Terminal error:
java.lang.NumberFormatException: For input string: "515.6499633789062"
   at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
   at java.lang.Integer.parseInt(Integer.java:492)
   at java.lang.Integer.parseInt(Integer.java:527)
   at com.vaadin.terminal.gwt.client.MouseEventDetails.deSerialize(MouseEventDetails.java:123)
   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:727)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.activiti.explorer.filter.ExplorerFilter.doFilter(ExplorerFilter.java:42)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
   at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
   at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
   at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
   at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
   at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
   at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
   at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
   at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
   at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
   at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
   at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
   at java.lang.Thread.run(Thread.java:745)
二月 11, 2015 3:27:31 下午 com.vaadin.Application terminalError
严重: Terminal error:
java.lang.NumberFormatException: For input string: "489.5699768066406"
   at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
   at java.lang.Integer.parseInt(Integer.java:492)
   at java.lang.Integer.parseInt(Integer.java:527)
   at com.vaadin.terminal.gwt.client.MouseEventDetails.deSerialize(MouseEventDetails.java:123)
   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:727)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.activiti.explorer.filter.ExplorerFilter.doFilter(ExplorerFilter.java:42)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
   at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
   at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
   at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
   at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
   at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
   at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
   at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
   at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
   at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
   at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
   at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
   at java.lang.Thread.run(Thread.java:745)
二月 11, 2015 3:27:31 下午 com.vaadin.Application terminalError
严重: Terminal error:
java.lang.NumberFormatException: For input string: "495.6499938964844"
   at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
   at java.lang.Integer.parseInt(Integer.java:492)
   at java.lang.Integer.parseInt(Integer.java:527)
   at com.vaadin.terminal.gwt.client.MouseEventDetails.deSerialize(MouseEventDetails.java:123)
   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:727)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.activiti.explorer.filter.ExplorerFilter.doFilter(ExplorerFilter.java:42)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
   at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
   at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
   at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
   at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
   at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
   at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
   at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
   at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
   at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
   at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
   at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
   at java.lang.Thread.run(Thread.java:745)
二月 11, 2015 3:27:31 下午 com.vaadin.Application terminalError
严重: Terminal error:
java.lang.NumberFormatException: For input string: "495.6499938964844"
   at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
   at java.lang.Integer.parseInt(Integer.java:492)
   at java.lang.Integer.parseInt(Integer.java:527)
   at com.vaadin.terminal.gwt.client.MouseEventDetails.deSerialize(MouseEventDetails.java:123)
   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:727)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.activiti.explorer.filter.ExplorerFilter.doFilter(ExplorerFilter.java:42)
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
   at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
   at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
   at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
   at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
   at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
   at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
   at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
   at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
   at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
   at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
   at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
   at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
   at java.lang.Thread.run(Thread.java:745)
"
So ,what does that mean? the error doesn't occur when i first deploy the web application.tks!

[jbarrez]

> java.lang.NumberFormatException: For input string: "486.9599914550781"

That string is coming from somewhere, and it's not Activiti itself. Any idea where this might come from?

[bmruter]

I am seeing the exact same error FF Chrome both work great, but when I open a task in IE11 I get the following…

Mar 6, 2015 10:29:36 AM com.vaadin.Application terminalError
SEVERE: Terminal error:
Throwable occurred: java.lang.NumberFormatException: For input string: "129.3300018310547"
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:59)
at java.lang.Integer.parseInt(Integer.java:469)
at java.lang.Integer.parseInt(Integer.java:510)
at com.vaadin.terminal.gwt.client.MouseEventDetails.deSerialize(MouseEventDetails.java:123)
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:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.activiti.explorer.filter.ExplorerFilter.doFilter(ExplorerFilter.java:42)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1074)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:897)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:919)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:738)
Mar 6, 2015 10:29:36 AM com.vaadin.Application terminalError
SEVERE: Terminal error:
Throwable occurred: java.lang.NullPointerException
at org.activiti.explorer.ExplorerApp.terminalError(ExplorerApp.java:246)
at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.handleChangeVariablesError(AbstractCommunicationManager.java:1564)
at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.handleVariableBurst(AbstractCommunicationManager.java:1425)
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:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.activiti.explorer.filter.ExplorerFilter.doFilter(ExplorerFilter.java:42)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:421)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1074)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:897)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:919)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:738)

[jbarrez]

Hmmm okay. How can I reproduce it? Simply open *any* task?

[trevorn]

I think this is a jar version issue - taking the hint from the poster I fixed this problem for myself by downloading a later version of the vaadin jar file.

To reproduce:
Environement:
Windows 7 x64 pro
Java 7 update 71
Tomcat 7.0.70, windows service install with a modified catalina-base
IE11.

As others have suggested I think the IE11 bit is critical, the rest doesn't matter.

Follow the quick start instructions using activiti-5.21.0
Open the start URL and log in as kermit.  The screen is fairly empty and if you click the Processes button you get the Internal Error and stack trace as reported.
Go to vaadin.com and download vaadin-6.8.17.jar.  Replace the 6.8.8 version in webapps\activiti-explorer\WEB-INF\lib with the new one.
Restart Tomcat and the error goes away.

What I do not know, and would like advice from the Activiti team on, is whether this update is likely to give other problems.  As a general principle I'm not too keen on poking around in the internals of somebody elses product like this. 

[aimingxu]

I am having exactly the same error on IE11. Chrome works fine. Does anyone know the solution?

[andrealuciano71]

Well,  IE 11 doesn't get along well with Vaadin 6.
A possible solution is to set a servlet filter in the web.xml file to add a header X-UA-Compatible to the http response.
An alternative remedy would be to upgrage Vaadin to 6.8 version according to this post https://dev.vaadin.com/ticket/12635.