Debugging a Failed JWrapper Build
If a build fails in JWrapper and you are using the JWrapper App, JWrapper will produce a log file in the same folder as your app project folder and will detail any errors that occur at the end of the log file:
Similarly if the build fails when you are running a JWrapper build from the command line, JWrapper will print out the cause of the error to the console. You can also have JWrapper produce a full log file by using the option -logtofile as part of the JWrapper command line:
If your JWrapper build completes successfully, but nothing happens or you see a failure when you run your app you can check the log files for your app to see exactly what point it reached, and why it failed.
Debugging your App Launch
Whenever your app runs using JWrapper, it sets up a folder on the local computer where it can save or cache files. This is the master folder for your app and can be found in the following locations:
For single-user and temporary runs the app is installed in the following places:
For all-user runs the app is installed in the following places:
The master folder will contain another folder called 'logs' where JWrapper launch components your app will log all output into separate files.
IMPORTANT: If you see a log file with your virtual app name prefixing it then the launch worked successfully but something caused your app to fail. The best thing to do at this point is to open the latest log file (the one from your virtual app) and check the end of the log file to find any errors and determine the cause of the problem.
Log files are circular so they won't go over 50MB in size and are also rotated so you won't see more than a handful of them for each virtual app. Log files are timestamped at launch so you can see the order the launch occurred in and they are also prefixed with the virtual app.
The order of launch for JWrapper is as follows:
If you only see a 'Wrapper' log file this would indicate something has caused the JWrapper launch to fail before it has reached your app.
For single-user and temporary runs the app is installed in the following places:
- Windows: %APPDATA%\JWrapper-AppName
- Linux: (user home dir)/.JWrapper/JWrapper-AppName
- MacOS: (user home dir)/Library/Application Support/JWrapper-AppName
For all-user runs the app is installed in the following places:
- Windows XP: %ALLUSERSPROFILE%\JWrapper-AppName
- Windows Vista or later: %PROGRAMDATA%\JWrapper-AppName
- Linux: /opt/JWrapper-AppName
- MacOS: /Library/Application Support/JWrapper-AppName
The master folder will contain another folder called 'logs' where JWrapper launch components your app will log all output into separate files.
IMPORTANT: If you see a log file with your virtual app name prefixing it then the launch worked successfully but something caused your app to fail. The best thing to do at this point is to open the latest log file (the one from your virtual app) and check the end of the log file to find any errors and determine the cause of the problem.
Log files are circular so they won't go over 50MB in size and are also rotated so you won't see more than a handful of them for each virtual app. Log files are timestamped at launch so you can see the order the launch occurred in and they are also prefixed with the virtual app.
The order of launch for JWrapper is as follows:
- Wrapper
- GenericUpdater
- Your virtual app
If you only see a 'Wrapper' log file this would indicate something has caused the JWrapper launch to fail before it has reached your app.