Link: Added: This issue depends JBIDE-1532

Just noticed this in the log:  workspace/.metadata/.log:

!ENTRY org.eclipse.ui 4 0 2007-12-21 08:50:04.403
!MESSAGE Unhandled event loop exception
!STACK 0
java.lang.NullPointerException
        at org.jbpm.gd.jpdl.properties.TaskFormGenerationDialog.getInputFile(Unknown Source)
        at org.jbpm.gd.jpdl.properties.TaskFormGenerationDialog.getFile(Unknown Source)
        at org.jbpm.gd.jpdl.properties.TaskFormGenerationDialog.createTaskFormFile(Unknown Source)
        at org.jbpm.gd.jpdl.properties.TaskFormGenerationDialog.generateForm(Unknown Source)
        at org.jbpm.gd.jpdl.properties.TaskFormGenerationDialog.okPressed(Unknown Source)
        at org.eclipse.jface.dialogs.Dialog.buttonPressed(Dialog.java:464)
        at org.eclipse.jface.dialogs.Dialog$2.widgetSelected(Dialog.java:616)
        at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:227)
        at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:66)
        at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1101)
        at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3319)
        at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:2971)
        at org.eclipse.jface.window.Window.runEventLoop(Window.java:820)
        at org.eclipse.jface.window.Window.open(Window.java:796)
        at org.jbpm.gd.jpdl.properties.TaskDetailsConfigurationComposite.handleFormButtonSelected(Unknown Source)
        at org.jbpm.gd.jpdl.properties.TaskDetailsConfigurationComposite.widgetSelected(Unknown Source)
        at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:227)
        at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:66)
        at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1101)
        at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3319)
        at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:2971)
        at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2389)
        at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2353)
        at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2219)
        at org.eclipse.ui.internal.Workbench$4.run(Workbench.java:466)
        at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:289)
        at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:461)
        at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
        at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:106)
        at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:169)
        at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:106)
        at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:76)
        at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:363)
        at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:176)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:585)
        at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:508)
        at org.eclipse.equinox.launcher.Main.basicRun(Main.java:447)
        at org.eclipse.equinox.launcher.Main.run(Main.java:1173)

Affects: Added: [Documentation (Ref Guide, User Guide, etc.)]

After a VNC session with Koen, the problem and its workarounds are:

--------------------------
On JBDS 1.0

The java.lang.NullPointerException only results when the user generates a form by maximizing the task's 'properties' dialog (i.e., the Eclipse 'properties' view). The 'Unknown Source' referred to in the exception stack trace is not the forms.xml file or the form's .xhtml file, but rather indicates that the GPD has lost its reference to the dialog itself.

Workaround - do not maximize the dialog when creating a task form. Note that on a smaller display such as a laptop, this makes for an awkward situation. I first found the problem while working on a laptop.

One other note on JBDS 1.0 - if a task name includes spaces, the spaces are converted to '-' characters in the name of the generated form .xhtml file. This seems to be a workaround to an ealier problem where if a task name included a space, the task form .xhtml file would not be generated.

--------------------------

On Eclipse 3.3.1.1 

If the user installs jbpm-jpdl-designer-3.1.2 (available as of Jan 10 2008) or 3.1.0.SP1 they will see the same behavior as above. Spaces in the task name are replaced by '-' in the generated form .xhtml file name.

--------------------------

So - the safest thing is to recommend that users do not maximize that dialog and don't have spaces in task names. 

--------------------------

Koen - just to confirm things - did you say that the properties-dialog-view-maximize problem was resolved in JBDS 1.0.1? Or, did you say that the spaces-in-task-names problem was resolved in JBDS 1.0.1?

The answer for SOA-P 4.2 is to document the problem (maximized dialog) in the IDE. 

http://engineering.redhat.com/docbot/en-US/JBoss_SOA_Platform/4.2/html-single/SOA_Release_Notes/#id2650632

Verified that the fix is here:

http://engineering.redhat.com/docbot/en-US/JBoss_SOA_Platform/4.2/html-single/SOA_Release_Notes/#id2650632