Drop the JetBrains Runtime requirement (#873)

Nothing in the desktop app needs the JBR anymore, so go back to OpenJDK
(Temurin 21) everywhere:

- Remove the JETBRAINS vendor pin from the desktop toolchain and from the
  launcher that jpackage bundles as the app runtime
- Replace the setup-jbr composite action with actions/setup-java; the
  retry logic only existed to survive rate limits on the jetbrains
  distribution's release listing
- Swap the JBR SDK tarball for Temurin 21 in the snap and flatpak builds,
  and verify the snap download's checksum
- Standardize the remaining 'adopt' setup-java steps on 'temurin'

.github/actions/setup-jbr/action.yml

@@ -1,64 +0,0 @@
-name: 'Set up JBR'
-description: 'Set up the JetBrains Runtime, retrying through transient GitHub rate limits on the JBR download.'
-
-inputs:
-  token:
-    description: 'GitHub token used for authenticated JBR downloads.'
-    required: true
-  cache:
-    description: "Build tool to cache dependencies for (passed through to setup-java's cache input). Empty disables caching."
-    required: false
-    default: ''
-
-runs:
-  using: 'composite'
-  steps:
-    - name: Set up JBR (attempt 1)
-      id: attempt1
-      uses: actions/setup-java@v5
-      continue-on-error: true
-      # The jetbrains distribution authenticates its release-listing API call via
-      # the GITHUB_TOKEN env var, not the `token` input — without it the request is
-      # unauthenticated and hits GitHub's per-IP rate limit.
-      env:
-        GITHUB_TOKEN: ${{ inputs.token }}
-      with:
-        distribution: 'jetbrains'
-        java-version: 21
-        token: ${{ inputs.token }}
-        cache: ${{ inputs.cache }}
-
-    - name: Back off before retry
-      if: steps.attempt1.outcome == 'failure'
-      shell: bash
-      run: sleep 30
-
-    - name: Set up JBR (attempt 2)
-      id: attempt2
-      if: steps.attempt1.outcome == 'failure'
-      uses: actions/setup-java@v5
-      continue-on-error: true
-      env:
-        GITHUB_TOKEN: ${{ inputs.token }}
-      with:
-        distribution: 'jetbrains'
-        java-version: 21
-        token: ${{ inputs.token }}
-        cache: ${{ inputs.cache }}
-
-    - name: Back off before final retry
-      if: steps.attempt1.outcome == 'failure' && steps.attempt2.outcome == 'failure'
-      shell: bash
-      run: sleep 60
-
-    # Final attempt: no continue-on-error, so a persistent failure still fails the job.
-    - name: Set up JBR (attempt 3)
-      if: steps.attempt1.outcome == 'failure' && steps.attempt2.outcome == 'failure'
-      uses: actions/setup-java@v5
-      env:
-        GITHUB_TOKEN: ${{ inputs.token }}
-      with:
-        distribution: 'jetbrains'
-        java-version: 21
-        token: ${{ inputs.token }}
-        cache: ${{ inputs.cache }}

.github/workflows/prepare-release.yml

@@ -15,8 +15,8 @@ jobs:
       - name: Set up JDK
         uses: actions/setup-java@v5
         with:
-          distribution: 'adopt'
-          java-version: 21
+          distribution: 'temurin'
+          java-version: '21'
           cache: gradle
 
       - name: Run Unit Tests
@@ -50,10 +50,11 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v7
 
-      - name: Set up JBR
-        uses: ./.github/actions/setup-jbr
+      - name: Set up JDK
+        uses: actions/setup-java@v5
         with:
-          token: ${{ secrets.GITHUB_TOKEN }}
+          distribution: 'temurin'
+          java-version: '21'
 
       - name: Gradle caching
         uses: actions/cache@v6
@@ -149,10 +150,11 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v7
 
-      - name: Set up JBR
-        uses: ./.github/actions/setup-jbr
+      - name: Set up JDK
+        uses: actions/setup-java@v5
         with:
-          token: ${{ secrets.GITHUB_TOKEN }}
+          distribution: 'temurin'
+          java-version: '21'
 
       - name: Gradle caching
         uses: actions/cache@v6
@@ -260,10 +262,11 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v7
 
-      - name: Set up JBR
-        uses: ./.github/actions/setup-jbr
+      - name: Set up JDK
+        uses: actions/setup-java@v5
         with:
-          token: ${{ secrets.GITHUB_TOKEN }}
+          distribution: 'temurin'
+          java-version: '21'
 
       - name: Gradle caching
         uses: actions/cache@v6
@@ -348,8 +351,8 @@ jobs:
       - name: Set up JDK
         uses: actions/setup-java@v5
         with:
-          distribution: 'adopt'
-          java-version: 21
+          distribution: 'temurin'
+          java-version: '21'
 
       - name: Gradle caching
         uses: actions/cache@v6
@@ -410,8 +413,8 @@ jobs:
       - name: Set up JDK
         uses: actions/setup-java@v5
         with:
-          distribution: 'adopt'
-          java-version: 21
+          distribution: 'temurin'
+          java-version: '21'
 
       - name: Gradle caching
         uses: actions/cache@v6
@@ -482,10 +485,11 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v7
 
-      - name: Set up JBR
-        uses: ./.github/actions/setup-jbr
+      - name: Set up JDK
+        uses: actions/setup-java@v5
         with:
-          token: ${{ secrets.GITHUB_TOKEN }}
+          distribution: 'temurin'
+          java-version: '21'
           cache: gradle
 
       - name: Grant Permission to Execute
@@ -520,10 +524,11 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v7
 
-      - name: Set up JBR
-        uses: ./.github/actions/setup-jbr
+      - name: Set up JDK
+        uses: actions/setup-java@v5
         with:
-          token: ${{ secrets.GITHUB_TOKEN }}
+          distribution: 'temurin'
+          java-version: '21'
           cache: gradle
 
       - name: Install Flatpak and flatpak-builder

desktop/build.gradle.kts

@@ -33,7 +33,6 @@ configurations.all {
 kotlin {
 	jvmToolchain {
 		languageVersion.set(JavaLanguageVersion.of(libs.versions.jvm.get().toInt()))
-		vendor.set(JvmVendorSpec.JETBRAINS)
 	}
 	jvm()
 	sourceSets {
@@ -77,15 +76,15 @@ kotlin {
 	}
 }
 
-// Pin jpackage's bundled runtime to the JetBrains Runtime.
-val jbrLauncher = javaToolchains.launcherFor {
+// Pin jpackage's bundled runtime to the project's toolchain JDK rather than
+// whichever JVM happens to be running Gradle.
+val packagingLauncher = javaToolchains.launcherFor {
 	languageVersion.set(JavaLanguageVersion.of(libs.versions.jvm.get().toInt()))
-	vendor.set(JvmVendorSpec.JETBRAINS)
 }
 
 compose.desktop {
 	application {
-		javaHome = jbrLauncher.get().metadata.installationPath.asFile.absolutePath
+		javaHome = packagingLauncher.get().metadata.installationPath.asFile.absolutePath
 		mainClass = "com.darkrockstudios.apps.hammer.desktop.MainKt"
 		nativeDistributions {
 			targetFormats(

flatpak/studio.darkrock.hammer.yaml

@@ -24,11 +24,11 @@ modules:
             build-args:
                 - --share=network
         build-commands:
-            # Extract JBR, setup environment, and build with Gradle
+            # Extract the JDK, setup environment, and build with Gradle
             # All in one command block so environment variables persist
             - |
-                tar -xzf jbr.tar.gz
-                export JAVA_HOME=$PWD/jbrsdk_jcef-21.0.9-linux-x64-b1163.86
+                tar -xzf jdk.tar.gz
+                export JAVA_HOME=$PWD/jdk-21.0.12+8
                 export PATH=$JAVA_HOME/bin:$PATH
                 java -version
                 chmod +x gradlew
@@ -54,6 +54,6 @@ modules:
             -   type: dir
                 path: ..
             -   type: file
-                url: https://cache-redirector.jetbrains.com/intellij-jbr/jbrsdk_jcef-21.0.9-linux-x64-b1163.86.tar.gz
-                sha256: 81d780fbea669d67a40a65a678ad0710d224c31439472d2d8933109c95cacf57
-                dest-filename: jbr.tar.gz
+                url: https://github.com/adoptium/temurin21-binaries/releases/download/jdk-21.0.12%2B8/OpenJDK21U-jdk_x64_linux_hotspot_21.0.12_8.tar.gz
+                sha256: e4446ff06a276155697597cc0f1b15da004ff083f4964a35271ecee567177370
+                dest-filename: jdk.tar.gz

settings.gradle.kts

@@ -7,7 +7,7 @@ pluginManagement {
     }
 }
 
-// F-Droid can't provide JBR or reach foojay, so skip both for F-Droid builds.
+// F-Droid can't reach foojay, so skip the toolchain resolver for F-Droid builds.
 // The flag is honoured from -Pfdroid=true, an `fdroid` entry in gradle.properties,
 // or the FDROID_BUILD environment variable - the same sources the module build
 // scripts read, so a single gradle.properties line drives the whole build.

snap/snapcraft.yaml

@@ -39,41 +39,38 @@ parts:
         override-build: |
             set -euo pipefail
 
-            # Download and setup JetBrains Runtime SDK (full JDK with jlink/jpackage)
-            # createDistributable bundles whatever JVM is in JAVA_HOME, so any
-            # silent fall-through to the container's OpenJDK ships a non-JBR
-            # runtime and the app crashes on startup with the Nucleus check.
-            echo "Downloading JetBrains Runtime SDK..."
-            wget https://cache-redirector.jetbrains.com/intellij-jbr/jbrsdk_jcef-21.0.9-linux-x64-b1163.86.tar.gz
-            tar -xzf jbrsdk_jcef-21.0.9-linux-x64-b1163.86.tar.gz
-            export JAVA_HOME=$PWD/jbrsdk_jcef-21.0.9-linux-x64-b1163.86
+            # A full JDK, not a JRE: createDistributable needs jlink/jpackage,
+            # and it bundles whatever JVM is in JAVA_HOME into lib/runtime/.
+            echo "Downloading Temurin JDK..."
+            wget https://github.com/adoptium/temurin21-binaries/releases/download/jdk-21.0.12%2B8/OpenJDK21U-jdk_x64_linux_hotspot_21.0.12_8.tar.gz -O jdk.tar.gz
+            echo "e4446ff06a276155697597cc0f1b15da004ff083f4964a35271ecee567177370  jdk.tar.gz" | sha256sum -c -
+            tar -xzf jdk.tar.gz
+            export JAVA_HOME=$PWD/jdk-21.0.12+8
             export PATH=$JAVA_HOME/bin:$PATH
 
-            # Fail fast if the JBR SDK extract didn't produce a usable toolchain.
+            # Fail fast if the extract didn't produce a usable toolchain.
             test -x "$JAVA_HOME/bin/java"
             test -x "$JAVA_HOME/bin/jlink"
             test -x "$JAVA_HOME/bin/jpackage"
 
-            echo "Building with JBR SDK (JAVA_HOME=$JAVA_HOME)"
+            echo "Building with JDK (JAVA_HOME=$JAVA_HOME)"
             java -version
 
             # Run gradle build with createDistributable
-            # This will now bundle JBR (not OpenJDK) in lib/runtime/
             chmod +x ./gradlew
             # First build all necessary JARs, then create the distributable
             ./gradlew :desktop:jvmJar --no-daemon
             ./gradlew :desktop:createDistributable -x desktopTest --no-daemon
             # Copy the gradle output to the install directory
             # Note: outputBaseDir is set to 'installers' in build.gradle.kts
-            # This includes the bundled JBR at lib/runtime/
+            # This includes the bundled runtime at lib/runtime/
             mkdir -p $CRAFT_PART_INSTALL/lib
             cp -r desktop/build/installers/main/app/hammer $CRAFT_PART_INSTALL/lib/hammer
             # Create the bin directory and launcher script
-            # Use the bundled JBR runtime instead of system OpenJDK
             mkdir -p $CRAFT_PART_INSTALL/bin
             cat > $CRAFT_PART_INSTALL/bin/hammer << 'EOF'
             #!/bin/bash
-            # Use the bundled JetBrains Runtime (JBR) that comes with the distributable
+            # Use the bundled runtime that comes with the distributable
             export JAVA_HOME=$SNAP/lib/hammer/lib/runtime
             export PATH=$JAVA_HOME/bin:$PATH
             exec $SNAP/lib/hammer/bin/hammer "$@"