How do we update bootstrap libraries about update4j

[mordechaim]

But how can we update the update4j, myapp-boot.jar, myapp.ini and myapp.exe in the installation folder (that are currently in use)?

update4j

The update4j file itself (currently) cannot be updated using this framework's features. The way to go would be to start the framework with a script or a set the classpath in a configuration file (as the case with javapackager, in MyApp.cfg that contains the classpath info) and when a new version is available download it with a newer version of these scripts/configuration pointing to the new file.

myapp-boot.jar

If you are using delegate mode, the philosophy is that you won't replace the existing files, instead you release a new delegate and increment the Delegate::version. Ideally, you could append a version number to the boot jar to match the delegate version (myapp-boot-v1.jar). If you're using modules, you must have a different module name from the old (since it doesn't really get replaced), so my.app.v1 should be ok.

myapp.ini

I would assume your ini file is texual, read by myapp.exe at app launch. In this case it doesn't get locked in any way.

myapp.exe

If you are on Windows (unclear, as the paths you gave point to Linux style, but exe isn't really Linux), there isn't any way you can update it. On Linux, files never get locked. Never!

On Linux it is safe to overwrite running executables, as the executable will still see the old version as long as it runs. But jar files aren't really executables but just zipped files read by the JVM, so overwriting them in a running instance is dangerous.

How can we work with relative instead of absolute paths in such a case?

Can you please elaborate your problem?
Do you mean that individual files in the config file are absolute and won't resolve against the base path?

[persal]

Thanks, will look at using delegate instead of our custom bootstrap class.
Also good to know where the limitations are. Hopefully updating the update4j library is not something that is needed very often.

Regarding paths. My understanding is that I have to provide absolute paths to where update libraries should be installed. But what if I want them to be updated in the relative path to "current directory", which is where "myapp.exe" is located.
Currently updates will be installed to "basePath" of not declared as absolute in the config.
Can I perhaps rewrite the "basePath" in my delegate?

We plan to have one installer for windows and a generic for others.

[mordechaim]

The delegation feature doesn't have any limitations over a standard custom bootstrap. You can still use your bootstrap, just replace your own main method with the delegate main and start the framework using update4j main method. Re relative paths, use can refer to properties listed in the config, as well to system properties: ${user.dir}/a/relative/path You can also make the basePath be the current dir this way.

[persal]

Added a delegate with works nicely with booting from update4js default Bootstrap. Also found user.dir very useful. I assume there are more of these "built-in" properties?

Appreciate all your help!

[mordechaim]

It's called system properties ;)

[persal]

Ah good to know that's how they get resolved. Didn't know user.dir was as widespread as user.home