Updates

installers generated by install4j actively handle updates. On the update options tab in the installer section, you can configure how an installer behaves in the event of an update.

The following points are of interest with respect to updates:

Generated installers will refuse to install on top of installations with a different application ID.
Note: installers generated with install4j <= 3.0 do no have an application ID, it is always possible to install on top of such an installation.
Generated installers will detect if any of the previously installed launchers are still running and will ask the user to shutdown these applications.
Deployed services will be stopped and uninstalled before the installation.
During an update, the installation databases will be merged, so that files, menu entries, file associations, etc. of old installations can still be uninstalled when the uninstaller is executed.
After an update, only the (optional) uninstall actions of the newer installation will be executed when the uninstaller is executed.
Optionally, generated installers can suggest the installation directory and program group of a previous installation.
Optionally, generated installers can run the uninstaller of a previous installation if they're installed in the same directory.

For distributing enhancements and patches, install4j offers the add-on installer type that can be configured on the update options tab in the installer section.

An add-on installer will only install on top of an installation of a specified install4j project. It does not have a separate uninstaller.