Build with Gradle in two modules, and free core of JavaFX

Etappen 1 and 2 of the Compose migration (43 commits).

The Maven build, the single source tree and the JPMS module-info went together.
core now holds the domain and app-desktop the user interface, both built by
Gradle, packaged through jpackage from Gradle, with SpotBugs and PMD wired in.
JavaFX moves to the classpath, which is why the launcher is Main and not the
Application subclass. The PR check, the nightly artifacts, the release and the
AUR packages all build from Gradle; the macOS DMG points at its output.
Verified on Linux, macOS and Windows.

core then loses JavaFX entirely. It observes through kst4contest.observe --
ObservableValue, ObservableRoster, and UiDispatcher as the one boundary a
worker thread crosses to touch the interface. The controller collections become
rosters and the visible station list a pure derivation rather than a
FilteredList/SortedList chain, which is also what fixed two focus defects only
a load test had exposed: the keyboard focus stays where the operator put it,
and the send field keeps it after a row click.

The rule that outlives this commit: ObservableRoster is the store and the list
a view is bound to is a mirror of it, never the other way round.

.github/workflows/nightly-artifacts.yml

@@ -5,12 +5,15 @@ on:
     branches:
       - main
     paths:
-      - "src/**"
       - "packaging/icons/**"
       - "packaging/macos/**"
-      - "pom.xml"
-      - "mvnw"
-      - "mvnw.cmd"
+      - "core/**"
+      - "app-desktop/**"
+      - "*.gradle.kts"
+      - "gradle.properties"
+      - "gradle/**"
+      - "gradlew"
+      - "gradlew.bat"
       - ".github/workflows/nightly-artifacts.yml"
   workflow_dispatch:
 
@@ -33,8 +36,7 @@ jobs:
       - name: Resolve nightly version info
         shell: pwsh
         run: |
-          $xml = [xml](Get-Content pom.xml)
-          $version = $xml.project.version
+          $version = (Select-String -Path gradle.properties -Pattern '^version=').Line.Split('=')[1]
           $shortSha = "${{ github.sha }}".Substring(0, 7)
           Add-Content -Path $env:GITHUB_ENV -Value "VERSION=$version"
           Add-Content -Path $env:GITHUB_ENV -Value "SHORT_SHA=$shortSha"
@@ -53,27 +55,26 @@ jobs:
       - name: Build JAR and copy runtime dependencies
         shell: pwsh
         run: |
-          .\mvnw.cmd -B -DskipTests package dependency:copy-dependencies -DincludeScope=runtime -DoutputDirectory=target/dist-libs
+          .\gradlew.bat -S :app-desktop:collectRuntime
           $jar = Get-ChildItem -Path target -Filter 'praktiKST-*.jar' | Sort-Object LastWriteTime -Descending | Select-Object -First 1
           if (-not $jar) {
             throw "No project JAR produced"
           }
-          Copy-Item $jar.FullName target/dist-libs/app.jar
+          Copy-Item $jar.FullName app-desktop/build/dist-libs/app.jar
 
       - name: Build app-image with jpackage
         shell: pwsh
         run: |
           New-Item -ItemType Directory -Force -Path dist | Out-Null
-          $addModules = & java packaging/AddModules.java
+          $addModules = (Select-String -Path gradle.properties -Pattern '^jpackageAddModules=').Line.Split('=')[1]
           if ($LASTEXITCODE -ne 0) { throw "Failed to resolve --add-modules from module-info.java" }
           jpackage `
             --type app-image `
             --name praktiKST `
             --icon packaging/icons/kst4contest.ico `
-            --input target/dist-libs `
+            --input app-desktop/build/dist-libs `
             --main-jar app.jar `
-            --main-class kst4contest.view.Kst4ContestApplication `
-            --module-path target/dist-libs `
+            --main-class kst4contest.view.Main `
             --add-modules $addModules `
             --dest dist
 
@@ -102,7 +103,7 @@ jobs:
 
       - name: Resolve nightly version info
         run: |
-          VERSION=$(grep -m1 '<version>' pom.xml | sed 's/.*<version>\(.*\)<\/version>.*/\1/')
+          VERSION=$(grep -m1 '^version=' gradle.properties | cut -d= -f2)
           SHORT_SHA="${GITHUB_SHA::7}"
           echo "ASSET_BASENAME=KST4Contest-${VERSION}-${SHORT_SHA}" >> "$GITHUB_ENV"
 
@@ -112,31 +113,30 @@ jobs:
           distribution: temurin
           java-version: "21"
 
-      - name: Ensure mvnw is executable
-        run: chmod +x mvnw
+      - name: Ensure gradlew is executable
+        run: chmod +x gradlew
 
       - name: Build JAR and copy runtime dependencies
         run: |
-          ./mvnw -B -DskipTests package dependency:copy-dependencies -DincludeScope=runtime -DoutputDirectory=target/dist-libs
-          cp "$(ls -t target/praktiKST-*.jar | head -n 1)" target/dist-libs/app.jar
+          ./gradlew -S :app-desktop:collectRuntime
 
       - name: Build app-image with jpackage
         run: |
           mkdir -p dist
-          ADD_MODULES="$(java packaging/AddModules.java)"
+          ADD_MODULES="$(grep -m1 '^jpackageAddModules=' gradle.properties | cut -d= -f2)"
           jpackage \
             --type app-image \
             --name KST4Contest \
             --icon packaging/icons/kst4contest.png \
-            --input target/dist-libs \
+            --input app-desktop/build/dist-libs \
             --main-jar app.jar \
-            --main-class kst4contest.view.Kst4ContestApplication \
-            --module-path target/dist-libs \
+            --main-class kst4contest.view.Main \
             --add-modules "$ADD_MODULES" \
             --dest dist
 
       - name: Create AppDir metadata
         run: |
+          mkdir -p target
           rm -rf target/KST4Contest.AppDir
           cp -a dist/KST4Contest target/KST4Contest.AppDir
 
@@ -163,6 +163,7 @@ jobs:
 
       - name: Build AppImage
         run: |
+          mkdir -p target
           wget -q -O target/appimagetool.AppImage https://github.com/AppImage/appimagetool/releases/download/continuous/appimagetool-x86_64.AppImage
           chmod +x target/appimagetool.AppImage
           APPIMAGE_EXTRACT_AND_RUN=1 ARCH=x86_64 target/appimagetool.AppImage target/KST4Contest.AppDir "dist/${ASSET_BASENAME}-linux-x86_64.AppImage"
@@ -184,7 +185,7 @@ jobs:
 
       - name: Resolve nightly version info
         run: |
-          VERSION=$(grep -m1 '<version>' pom.xml | sed 's/.*<version>\(.*\)<\/version>.*/\1/')
+          VERSION=$(grep -m1 '^version=' gradle.properties | cut -d= -f2)
           SHORT_SHA="${GITHUB_SHA::7}"
           echo "ASSET_BASENAME=KST4Contest-${VERSION}-${SHORT_SHA}" >> "$GITHUB_ENV"
 
@@ -199,26 +200,24 @@ jobs:
           sudo apt-get update -qq
           sudo apt-get install -y --no-install-recommends fakeroot
 
-      - name: Ensure mvnw is executable
-        run: chmod +x mvnw
+      - name: Ensure gradlew is executable
+        run: chmod +x gradlew
 
       - name: Build JAR and copy runtime dependencies
         run: |
-          ./mvnw -B -DskipTests package dependency:copy-dependencies -DincludeScope=runtime -DoutputDirectory=target/dist-libs
-          cp "$(ls -t target/praktiKST-*.jar | head -n 1)" target/dist-libs/app.jar
+          ./gradlew -S :app-desktop:collectRuntime
 
       - name: Build Debian package
         run: |
           mkdir -p dist
-          ADD_MODULES="$(java packaging/AddModules.java)"
+          ADD_MODULES="$(grep -m1 '^jpackageAddModules=' gradle.properties | cut -d= -f2)"
           jpackage \
             --type deb \
             --name KST4Contest \
             --icon packaging/icons/kst4contest.png \
-            --input target/dist-libs \
+            --input app-desktop/build/dist-libs \
             --main-jar app.jar \
-            --main-class kst4contest.view.Kst4ContestApplication \
-            --module-path target/dist-libs \
+            --main-class kst4contest.view.Main \
             --add-modules "$ADD_MODULES" \
             --linux-package-deps "libgstreamer1.0-0,libgstreamer-plugins-base1.0-0,gstreamer1.0-plugins-good" \
             --dest dist
@@ -245,7 +244,7 @@ jobs:
 
       - name: Resolve nightly version info
         run: |
-          VERSION=$(grep -m1 '<version>' pom.xml | sed 's/.*<version>\(.*\)<\/version>.*/\1/')
+          VERSION=$(grep -m1 '^version=' gradle.properties | cut -d= -f2)
           SHORT_SHA="${GITHUB_SHA::7}"
           echo "ASSET_BASENAME=KST4Contest-${VERSION}-${SHORT_SHA}" >> "$GITHUB_ENV"
 
@@ -260,26 +259,24 @@ jobs:
           sudo apt-get update -qq
           sudo apt-get install -y --no-install-recommends rpm
 
-      - name: Ensure mvnw is executable
-        run: chmod +x mvnw
+      - name: Ensure gradlew is executable
+        run: chmod +x gradlew
 
       - name: Build JAR and copy runtime dependencies
         run: |
-          ./mvnw -B -DskipTests package dependency:copy-dependencies -DincludeScope=runtime -DoutputDirectory=target/dist-libs
-          cp "$(ls -t target/praktiKST-*.jar | head -n 1)" target/dist-libs/app.jar
+          ./gradlew -S :app-desktop:collectRuntime
 
       - name: Build Fedora package
         run: |
           mkdir -p dist
-          ADD_MODULES="$(java packaging/AddModules.java)"
+          ADD_MODULES="$(grep -m1 '^jpackageAddModules=' gradle.properties | cut -d= -f2)"
           jpackage \
             --type rpm \
             --name KST4Contest \
             --icon packaging/icons/kst4contest.png \
-            --input target/dist-libs \
+            --input app-desktop/build/dist-libs \
             --main-jar app.jar \
-            --main-class kst4contest.view.Kst4ContestApplication \
-            --module-path target/dist-libs \
+            --main-class kst4contest.view.Main \
             --add-modules "$ADD_MODULES" \
             --linux-package-deps "gstreamer1,gstreamer1-plugins-base,gstreamer1-plugins-good" \
             --dest dist
@@ -306,7 +303,7 @@ jobs:
 
       - name: Resolve nightly version info
         run: |
-          VERSION=$(grep -m1 '<version>' pom.xml | sed 's/.*<version>\(.*\)<\/version>.*/\1/')
+          VERSION=$(grep -m1 '^version=' gradle.properties | cut -d= -f2)
           SHORT_SHA="${GITHUB_SHA::7}"
           echo "VERSION=$VERSION" >> "$GITHUB_ENV"
           echo "SHORT_SHA=$SHORT_SHA" >> "$GITHUB_ENV"
@@ -323,31 +320,30 @@ jobs:
           sudo apt-get update -qq
           sudo apt-get install -y --no-install-recommends zstd
 
-      - name: Ensure mvnw is executable
-        run: chmod +x mvnw
+      - name: Ensure gradlew is executable
+        run: chmod +x gradlew
 
       - name: Build JAR and copy runtime dependencies
         run: |
-          ./mvnw -B -DskipTests package dependency:copy-dependencies -DincludeScope=runtime -DoutputDirectory=target/dist-libs
-          cp "$(ls -t target/praktiKST-*.jar | head -n 1)" target/dist-libs/app.jar
+          ./gradlew -S :app-desktop:collectRuntime
 
       - name: Build app-image with jpackage
         run: |
           mkdir -p dist
-          ADD_MODULES="$(java packaging/AddModules.java)"
+          ADD_MODULES="$(grep -m1 '^jpackageAddModules=' gradle.properties | cut -d= -f2)"
           jpackage \
             --type app-image \
             --name KST4Contest \
             --icon packaging/icons/kst4contest.png \
-            --input target/dist-libs \
+            --input app-desktop/build/dist-libs \
             --main-jar app.jar \
-            --main-class kst4contest.view.Kst4ContestApplication \
-            --module-path target/dist-libs \
+            --main-class kst4contest.view.Main \
             --add-modules "$ADD_MODULES" \
             --dest dist
 
       - name: Build Arch Linux package artifact
         run: |
+          mkdir -p target
           ARCH=$(uname -m)
           PKGVER=$(printf '%s' "${VERSION}-${SHORT_SHA}" | sed 's/[^[:alnum:].+_]/_/g')
           PKGROOT="target/archpkg"
@@ -427,7 +423,7 @@ jobs:
 
       - name: Resolve nightly version info
         run: |
-          VERSION=$(grep -m1 '<version>' pom.xml | sed 's/.*<version>\(.*\)<\/version>.*/\1/')
+          VERSION=$(grep -m1 '^version=' gradle.properties | cut -d= -f2)
           SHORT_SHA="${GITHUB_SHA::7}"
           echo "VERSION=$VERSION" >> "$GITHUB_ENV"
           echo "SHORT_SHA=$SHORT_SHA" >> "$GITHUB_ENV"
@@ -439,8 +435,8 @@ jobs:
           distribution: temurin
           java-version: "21"
 
-      - name: Ensure mvnw is executable
-        run: chmod +x mvnw
+      - name: Ensure gradlew is executable
+        run: chmod +x gradlew
 
       - name: Install Flatpak tooling
         run: |
@@ -451,23 +447,22 @@ jobs:
 
       - name: Build app-image with jpackage
         run: |
-          ./mvnw -B -DskipTests package dependency:copy-dependencies -DincludeScope=runtime -DoutputDirectory=target/dist-libs
-          cp "$(ls -t target/praktiKST-*.jar | head -n 1)" target/dist-libs/app.jar
+          ./gradlew -S :app-desktop:collectRuntime
           mkdir -p target/flatpak-src
-          ADD_MODULES="$(java packaging/AddModules.java)"
+          ADD_MODULES="$(grep -m1 '^jpackageAddModules=' gradle.properties | cut -d= -f2)"
           jpackage \
             --type app-image \
             --name KST4Contest \
             --icon packaging/icons/kst4contest.png \
-            --input target/dist-libs \
+            --input app-desktop/build/dist-libs \
             --main-jar app.jar \
-            --main-class kst4contest.view.Kst4ContestApplication \
-            --module-path target/dist-libs \
+            --main-class kst4contest.view.Main \
             --add-modules "$ADD_MODULES" \
             --dest target/flatpak-src
 
       - name: Create Flatpak manifest
         run: |
+          mkdir -p target
           mkdir -p dist
           cat > target/de.x08.KST4Contest.yml << 'EOF'
           app-id: de.x08.KST4Contest
@@ -515,6 +510,7 @@ jobs:
 
       - name: Build Flatpak repo (nightly)
         run: |
+          mkdir -p target
           flatpak-builder --force-clean target/flatpak-build target/de.x08.KST4Contest.yml
           flatpak build-export --gpg-sign="$FLATPAK_GPG_KEY_ID" target/flatpak-repo target/flatpak-build nightly
           flatpak build-update-repo --gpg-sign="$FLATPAK_GPG_KEY_ID" target/flatpak-repo
@@ -622,7 +618,7 @@ jobs:
 
       - name: Resolve nightly version info
         run: |
-          VERSION=$(grep -m1 '<version>' pom.xml | sed 's/.*<version>\(.*\)<\/version>.*/\1/')
+          VERSION=$(grep -m1 '^version=' gradle.properties | cut -d= -f2)
           SHORT_SHA="${GITHUB_SHA::7}"
           ARCH=$(uname -m)
           echo "VERSION=$VERSION" >> "$GITHUB_ENV"
@@ -636,8 +632,8 @@ jobs:
           distribution: temurin
           java-version: "21"
 
-      - name: Ensure mvnw is executable
-        run: chmod +x mvnw
+      - name: Ensure gradlew is executable
+        run: chmod +x gradlew
 
       - name: Import signing certificate
         env: