Randon application closes

[jcanal]

using a Java application in the Nokia 6600 it works fine but randomly I get the following message

jes-220-javax.microedition.lcdui1@1..

and the application is closed. Starting again the application it closes in a completely different action.

Does anybody know the meaning of this message?
There is any way to see the full message text? What is missing it may provide some additional hints about the source of the problem.

I have not been able to reproduce the same problem in the S60 nokia emulator neither in the Sun wireless toolkit.

The application has been developed using Jbuilder V9.

Thanks for help or suggestions on how to debug this problem.

[dpolyakov]

Some ideas how to debug on the phone:
1. print the text out to the screen of you phone
2. Use RMS. Write your text, IDs or whatever you will decide to storage. When you run your application, you have to display last stored record - it will show you between which check points it is happening.

It seems to me that you have a memory problem. May be one of your class members points into null and then you use this variable somewhere.

Dima.
Game Artists, LLC
www.gameartists.com

[mrmop]

It could be a memory leak, or you may have fragmented the heap by creating and destroying many objects? Also as it appears to be a lcdui associated problem, you may want to check the parametsr to your methods. Could you tell us a little more about what your program does?

[pichelmn]

I have the same thing happen to two applications I have. Seems to happen when switching screens. Sometimes the application won't even come up, while other times it works fine for a while before showing the error.

I've seen suggestions that this could have to do with loading images, but the only images I have are on the main menu, which it seems to crash everywhere.

[dpolyakov]

> I've seen suggestions that this could have to do with loading images, but the only images I have are on the main menu, which it seems to crash everywhere.

We have discussed a lot about that.

Dima
GameArtists.com

[pichelmn]

I went through a bunch of posts and ran across one that had the a link to issues on the 6600, which seems to have solved my issues.

The pdf is at: http://nds1.forum.nokia.com/nnds/For...5F0%5Fen%2Epdf

My issue looks to be that I was using setCurrent(alert, nextDisplayable) - since I've removed these calls I haven't seen any issues.

Hopefully this will help you too.

Keith
Concrete Software

[jcanal]

I have done additional test on the crashing application and it happens in the following scenario, the problem involves. Form A, (the main menu and starting point for the application), forms B, C, D and few forms more that are not involved in the crashing sequence. Each form is implemented in a separate class and the jar file is 60Kb.

The sequence that crashes is as follow: once the main menu is displayed (form A) open form B, close form B, open form B, close form B and then open form C and try to navigate to form D which is one of the options available in form C. The application crashes almost always, the sequence is very simple, no data needs to be changed in any of the used screens.

If the sequence is from main menu (form A) open form C and then open form D, It works well even if you try the above mentioned sequence.

Since there is at least a repeatable sequence I been working to locate the point where the application crashes and try to find a workaround, the results are not satisfactory since I have not been able to find it, my conclusions are:

The problem is related to form switching (the setCurrent(alert, nextForm) is not used, there are no alerts in this application).
It seems to be related with some kind of timing.
Some times to be able to reproduce the problem the phone had to be switched off and on.
The same problem has been tested in the emulators (nokia and sun) and never appeared.
The problem appears randomly in other places of the application but always the user action involves a screen switch (navigate to the next or to the previous)

Finally I have produced a reduced version (only the form involved in the crashing sequence) but in this version I had not been able to reproduce the problem.

Reading the forum it seems to be a kind of problem that has been reported by many developers and nobody has found a solution or workaround.

There is anybody that have done similar work to find the workaround, it will be interesting to share details.

There is anybody that knows how to involve Nokia in fixing this issue?

[tzihx2]

personally i feel that when switch to a screen that creates new resources like new image, then there is a chance the app will crash..

but strangely, the first time initialization seldom cause problem.. problem only occurs when the re-creation or re-initialization..

[jcanal]

In my case there is only one image that is used in the firts screen.

When the app crashes no new images are created.

[pichelmn]

We have a few applications that had this crashing issue. One in particular has a main menu and lots of different screens.

I could get this application to crash by going to the instructions screen over and over - usually around the 10th time to the screen (no images on this screen). Watching the available memory - it looks as though memory was getting low at the point of the crash - which tells me this is probably either caused by fragmentation in the heap or problems with the garbage collector in the JVM?

Each screen I was going to, including the instruction screen, I was creating a new instance of it each time. I changed all my screens to now initialize at startup - I keep one instance of each and have a refresh method that I call just before going to each to update the screen appropriately. Now it looks like the crashes I was having previously are gone (or very hard to get to now).

The other things I did were remove pretty much all alerts. I also removed the image from our starting splash screen - we set the splash screen and started a new thread to load everything (crashed starting up about 10% of the time, when I caught the exception it said ' 0 ' - not real helpful!).

Keith
Concrete Software