texty3

A minimal text editor, third in a series - the first in C, the second using python-Gtk and now this one written in Java and using Java-GI Gtk/Adw bindings. Each is packaged as a flatpak. The first two were developed in GNOME Builder and this one I developed in eclipse using a modified fork of the uk.co.bithatch:maven-flatpak-plugin to create flatpak artifacts. Have a look at the pom.xml configuration for details.

The code is compiled with Java 22 (the minimum for Java-GI) and is packaged in a container with flatpak runtime org.gnome.Platform and org.gnome.Sdk 48 that includes the openjdk-23.0.2 JRE that runs the application.

Prerequisites

You'll need flatpak and a Java JDK >= 22 installed.

Along the way you may get some errors about missing flatpak runtimes. These can be fixed by installing them via, e.g.:

flatpak install flathub org.gnome.Platform

Building

If you're using eclipse, use the texty3-BUILD.launch run configuration. Or run:

mvn clean package ca.footeware:flatpak-maven-plugin:generate

This populates the target folder, including an app folder with artifacts needed for a flatpak-builder call. The app folder should look like this:

❯ tree ./app
./app
├── ca.footeware.java.texty3.desktop
├── ca.footeware.java.texty3.metainfo.xml
├── ca.footeware.java.texty3.svg
├── ca.footeware.java.texty3.yml
├── texty3
└── texty3.jar

From the app folder, run the following to build the flatpak and install it locally.

flatpak-builder --force-clean --user --verbose --install build-dir ca.footeware.java.texty3.yml

If you get errors, running this can provide better explanations. Some pom.xml tags are used but I think I've got the required ones.

flatpak run --command=flatpak-builder-lint org.flatpak.Builder appstream ca.footeware.java.texty3.metainfo.xml

Running

To run the installed flatpak, use:

flatpak run ca.footeware.java.texty3

Or use the launcher that should now be in your apps view. Or use Warehouse.

Export to .flatpak file

This can be double-clicked to install in GNOME Software.

1. flatpak-builder --repo=repo --force-clean build-dir ca.footeware.java.texty3.yml
2. flatpak build-bundle repo ca.footeware.java.texty3.flatpak ca.footeware.java.texty3

Debugging

Warehouse is a great program to manage flatpaks, including verifying installation, running and removal.

Note that the flatpak-builder --force-clean --user --verbose --install build-dir ca.footeware.java.texty3.yml command as described above installs the app with user scope while installing the .flatpak build will install in system scope. This needs reconciliation.

A couple commands I've found that might help:

• Source verification: flatpak run --command=flatpak-builder-lint org.flatpak.Builder appstream ca.footeware.java.texty3.metainfo.xml
• Container info: flatpak info ca.footeware.java.texty3
• Attach to running container: flatpak run --command=sh ca.footeware.java.texty3. Once connected, cd /app to see your files. You can check the version of java installed in /app/jre.

Removing

To remove this fine piece of work, use Warehouse or run:

flatpak uninstall --delete-data ca.footeware.java.texty3

TODO

• Code tweaks.
• Release texty3.flatpak as installable on clients.
• Consider integrating flatpak-builder calls.

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