Exceptions thrown using step function in Probe interfaced with PVManager

[arnaudf-iter]

An exception occurs every seconds when typing "=step(10,10)" for example in Probe interfaced with PVManager and no result is displayed.

2013-10-21 08:34:49.059 SEVERE [Thread 1] org.csstudio.logging.PluginLogListener (logging) - Unhandled event loop exception
org.eclipse.swt.SWTException: Failed to execute runnable (java.lang.RuntimeException: Values for type  are not setup for notification.)
    at org.eclipse.swt.SWT.error(SWT.java:4282)
    at org.eclipse.swt.SWT.error(SWT.java:4197)
    at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:138)
    at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3563)
    at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3212)
    at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2701)
    at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2665)
    at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2499)
    at org.eclipse.ui.internal.Workbench$7.run(Workbench.java:679)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:668)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
    at org.csstudio.utility.product.Workbench.runWorkbench(Unknown Source)
    at org.csstudio.startup.application.Application.startApplication(Unknown Source)
    at org.csstudio.startup.application.Application.start(Unknown Source)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:344)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
    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:601)
    at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:622)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:577)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1410)
    at org.eclipse.equinox.launcher.Main.main(Main.java:1386)
Caused by: java.lang.RuntimeException: Values for type  are not setup for notification.
    at org.epics.pvmanager.NotificationSupport.notification(NotificationSupport.java:42)
    at org.epics.pvmanager.PVReaderDirector$1.run(PVReaderDirector.java:301)
    at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
    at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:135)
    ... 25 more

[gcarcassi]

At this point, only VTypes can be output of formulas. step() returns a NumberListProvider (or something like that), so you get the error. It's not clear to me why the name of the type is not in the exception message, though: the code is there.

[kasemir]

What is a correct example for using step()?
Input of table widget? Or part of expression within a formula, just not overall result of formula?

[gcarcassi]

The step function is meant to be used as part of formulas. For example:
tableOf(column("index", step(0,1)), column("values", 'mywaveform'))
The first column will go 0, 1, 2, 3, 4, ... until the end of the waveform arrives.

The point is that the output of step is not a VType. Like the column() function does not return a vType and makes no sense to use directly.

Maybe we can have a better error message, but the fact that you get an error is intended.

[berryma4]

Changing the error message could be in this version, but changing behavior would need to go to 3.3.x.
What would you like Frederic?

[arnaudf-iter]

As a first step, changing the error message is enough for us.

[berryma4]

Gabriele, can you change the error message in 3.2.13? And, we can move the
discussion on function behavior to 3.3.x.

On Thu, Dec 5, 2013 at 6:05 AM, arnaudf-iter notifications@github.comwrote:

As a first step, changing the error message is enough for us.

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/164#issuecomment-29889016
.

[gcarcassi]

The trick is that I need a message that is good for both the programmer and the end user... I'll think of something.

[gcarcassi]

This should be better:

Also: the exception in not generated anymore on the SWT thread.

[berryma4]

Did you want to merge this to master also, or do you have other plans?

[gcarcassi]

Will be merged to trunk with the new version of pvmanager in January. This was a simple patch for 3.2 that touches fewest things as possible.

[berryma4]

Thank you , closing ticket.