Having some trouble with try/catch in UiPath:
Got two different projects with their own workflows, with try catch implementations exactly the same in both.
However, one of the try/catch is working absolutely fine, whereas the other one is giving troubles with the following error when I Throw an exception, and then the steps defined in the catch block doesn't even trap it and execute.
Thoughts/Suggestions will be much appreciated - Thanks!
RemoteException wrapping System.Exception: <My user defined message>
at System.Activities.Statements.Throw.Execute(CodeActivityContext context)
at System.Activities.CodeActivity.InternalExecute(ActivityInstance instance, ActivityExecutor executor, BookmarkManager bookmarkManager)
at System.Activities.ActivityInstance.Execute(ActivityExecutor executor, BookmarkManager bookmarkManager)
at System.Activities.Runtime.ActivityExecutor.ExecuteActivityWorkItem.ExecuteBody(ActivityExecutor executor, BookmarkManager bookmarkManager, Location resultLocation)
If you have been using the Try Catch with the general Exception, it should be working in the same way in any project.
I believe you was a bit confused by the running mode.
So I assume in one project you fired the project in the debug mode. This stops on the exception when it occurs. If happening you need to hit the continue button.
But if you run the project with the Run button, it will ignore the exception handling as breakpoint and will continue now without any break.
So make sure in a live test you always run it with the run button and not with the usual debug button.
Related
Within a Codename1 app, I'm getting a CrashReport: java.lang.NullPointException: Attempt to invoke virtual method 'void android.graphics.Point.setAntiAlias(boolean)' on a null object reference. This seems to occur after I invoke a "show()" on the main form of my application.
Note that the code runs fine in the simulator, but consistently gets this error prior to doing the "show()" on Android.
Interestingly, if I put a Dialog like this:
Dialog.show("Wait a sec", "Showing interrupt point", "OK", null);
before the .show(), and then click "OK", then everything runs well with no exceptions at all.
But a sleep(5000) instead of the Dialog does not help - still get the exception. So it at least seems like its not a race condition.
I have try-catches wrapped around all of the potentially offending code, and have NOT been able to isolate this. It always gets caught by the CrashReport, and only when running on the Android device.
Any ideas?
The symptoms to this one are pretty strange (i.e. workaround with a Dialog), and it would be interesting to have an explanation. However, since deprecated cn1 (Map) code has seemingly been implicated, I'm going to let this one go and replace this code with the latest Google native maps code. If it recurs, I will post another question then.
I'm trying to catch "nrpe unable to read output" output from plugin and send an email when this one occurs and I'm a little bit stuck :) . Thing is there are different return codes when this error occurs on different plugin:
Return code Service status
0 OK
1 WARNING
2 CRITICAL
3 UNKNOWN
Is there a way either to unify return codes of all plugins I use(that there always will be 2[CRITICAL] when this problem occurs), or any other way to catch those alerts? I want to keep return codes for different situations as is(i.e. filesystem /home will be warning(return code 1) for 95% and critical(return code 2) for 98%
Most folks would rather not have this error sending alert emails, because it does not represent an actual failed check. Basically it means nothing more than:
The command/plugin (local or remote) was ran by NRPE, but
failed to return any usable status and/or text back to nrpe.
This most often means something went wrong with the command/plugin and it hasn't done the job it was expected to perform. You don't want alerts being thrown for checks, when the check wasn't actually performed - as this would be very misleading. It's also important to note that the Return Code is not even be coming from the command/plugin.
In my experience, the number one cause of this error is a bad check. And as the docs for NPRE state, you should run the check (with all its options!) to make sure it runs correctly. Do yourself a favor and test both working AND not working states. About 75% of the time, this has happened because the check only works correctly when it has OK results, and blows up when something not-OK must be reported.
Another issue that causes these are network glitches. NRPE connects and runs the check; but the connection is closed before any response is seen. Once again, not a true check result.
For a production Nagios monitoring system, these should be very rare errors. If they are happening frequently, then you likely have other issues that need to be fixed.
And as far as I can tell, all built-in Nagios plugins use the exact same set of return codes. Are you certain this isn't a 'custom' check?
Ok, I think I've found the solution for my problems-I will try to check nagios.log on each node for those errors.
I have an app that used to work well, I did some modifications and such. Now, only about 1/2 the time it runs. I installed the app to a laptop and it doesn't run at all.
There are no errors, warnings, or ui shown by the task bar shows the app momentarily.
Even when I run inside visual studio and put a break point on InitalizeComponent(), I can't seem to locate anything causing the problem.
My code essentially looks like this:
Application.Current.DispatcherUnhandledException += Current_DispatcherUnhandledException;
this.Dispatcher.UnhandledException += Dispatcher_UnhandledException;
try
{
InitializeComponent();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
log("Initalizing....");
This is wpf 4 in vs2015. Any ideas how to get some type of error message before it exits and figure out what is causing the problem? The app works fine once it actually runs. The event viewer on the laptop shows some messages, something about faulting in KernalBase.... nothing useful.
I'm not sure if InitalizeComponent() is the issue, but when I put a BP on it and step through the code, it always exits at that point.
As #Breeze mentioned, you need to strengthen the exceptions, like that:
Go to Debug -> Exceptions... OR Ctrl+Alt+E and you'll see this window:
Mark this two:
Common Language Runtime Exceptions and
Manage Debbugging Assistants.
REMEMBER after finish using them unmark them because it also throws exceptions you don't need to deal with a lot of times.
We can use multiple catch block in Try-Catch.
But my Question is : why to use multiple catch blocks when it can be done by using single catch block?
Suppose I want exact cause of my problem, I can get that by Ex.message
If I want to show customized message to user, I can show it by putting If-Else loop on Ex.Message.
Thanks in advance.
To handle the individual exception accordingly.
For example:
If your program is handling both database and files. If an SQLException occurs, you have to handle it database manner like closing the dbConnection/reader etc., whereas if a File handling exception then you may handle it differently like file closing, fileNotFound etc.
That is the main reason in my point of view.
For point numbers 1 and 2:
If showing error message is you main idea then you can use if..else. In case if you want to handle the exception then check the above point of my answer. The reason why I stretch the word handling is because it is entirely different from showing a simple error message.
To add some quotes I prefer Best Practices for Handling Exceptions which says
A well-designed set of error handling code blocks can make a program
more robust and less prone to crashing because the application handles
such errors.
This works only if all exceptions share the same base class, then you could do it this way.
But if you do need exception type specific handling, then I would prefer multiple try-catch blocks instead of one with type-depending if-else ...
You can also ask why do we need the Switch - Case. You can do it with If - Else.
And why do you need Else at all. You can do it with If (If not the first condition, and...).
It's a matter of writing a clean and readable code.
By using single catch clock you can catch Exception type - this practice is strongly discouraged by Microsoft programming guidelines. FxCop has the rule DoNotCatchGeneralExceptionTypes which is treated as CriticalError:
Catching general exception types can hide run-time problems from the library user, and can complicate debugging.
http://code.praqma.net/docs/fxcop/Rules/Design/DoNotCatchGeneralExceptionTypes.html
The program should catch only expected exception types (one ore more), leaving unexpected types unhandled. To do this, we need possibility to have multiple catch blocks. See also:
Why does FxCop warn against catch(Exception)?
http://blogs.msdn.com/b/codeanalysis/archive/2006/06/14/631923.aspx
when I use XamlReader.Load() with an invalid XAML string, the resulting XAMLParseException is not caught although beeing in a try-catch-block:
try
{
UIElement xamlCode = XamlReader.Load(XamlText) as UIElement;
}
catch (Exception ex)
{
ErrorText = ex.Message;
}
The code is called from the Tick-Event of a DispatcherTimer, but also in Events like MouseLeftButtonDown the exception is not caught resulting in a break in the Line where I call .Load().
Does anyone know how to catch this Exception and resume normal programm activity?
Thanks, Andrej
It is completely unfathomable that this code would not catch the exception. How do you determine that the XAMLParseException is occuring here? Are you sure is not coming from some other Xaml Load in the project?
Is this always the case ? or onlys while debugging ?
I'm aware this is an extremely late answer and you might have found the solution to it, for as reference to people finding your question similar to theirse (like my case ), my answer might still be of use.
If its happening while debuggin, it might be because the exeption is configured to be thrown.
You can change this:
Customize the Debug menu, adding the "Exceptions" command to it.
In the Exceptions configuration, Drill down to System.Windows.Markup.XamlParseException, which is under Common Language Runtime Exceptions.
Remove the check from the "Throw" column.
There are various Silverlight operations that get "re-marshalled" onto separate threads for what are presumably various good and sufficient reasons. It looks kind of like this:
Dispatcher.BeginInvoke(() => LoadSomeXamlOrSomething());
Any exception thrown within LoadSomeXamlOrSomething() won't be caught by normal try/catch blocks. This happens even in SL 4 with things like loading images with invalid formats. It's annoying, and MS needs to come up with a better way to handle this, for instance, by letting you register an exception handler when you make the call.
Until MS figures this out, your options are:
Fix the underlying XAML error.
Catch the exception in App.Application_UnhandledException.