Fix jreleaserDeploy JGit conflict and dry-run it in CI (#1728)

Author: donatello

.github/workflows/gradle.yml

@@ -58,6 +58,23 @@ jobs:
         run: |
           ./gradlew.bat build
 
+      - name: Run release deploy in dry-run mode
+        if: matrix.os == 'ubuntu-latest' && matrix.java-version == '25'
+        env:
+          GNUPGHOME: ${{ runner.temp }}/gnupg
+          JRELEASER_GPG_PUBLIC_KEY: ${{ runner.temp }}/public.asc
+          JRELEASER_GPG_SECRET_KEY: ${{ runner.temp }}/private.asc
+          JRELEASER_GPG_PASSPHRASE: dry-run
+          NEXUS_USERNAME: dry-run
+          NEXUS_PASSWORD: dry-run
+        run: |
+          # Throwaway signing key and dummy credentials; --dryrun skips all remote operations.
+          mkdir -m 700 "$GNUPGHOME"
+          gpg --batch --passphrase "$JRELEASER_GPG_PASSPHRASE" --quick-gen-key 'minio-java CI <ci@example.invalid>' rsa3072 sign never
+          gpg --batch --armor --export > "$JRELEASER_GPG_PUBLIC_KEY"
+          gpg --batch --pinentry-mode loopback --passphrase "$JRELEASER_GPG_PASSPHRASE" --armor --export-secret-keys > "$JRELEASER_GPG_SECRET_KEY"
+          ./gradlew publishMinioJavaPublicationToPreDeployRepository jreleaserDeploy --dryrun -Prelease
+
       - name: Setup java ${{ matrix.java-version }} for testing
         if: matrix.java-version != '25'
         uses: actions/setup-java@v6

build.gradle

@@ -18,6 +18,16 @@
 /*   gradleVersion = '9.8.2'    */
 /********************************/
 
+buildscript {
+    configurations.classpath {
+        // JReleaser 1.26.0 is built against JGit 5.13 and fails with NoClassDefFoundError
+        // org/eclipse/jgit/lib/GpgObjectSigner (removed in JGit 7) when Spotless 8.x pulls JGit 7
+        // onto the shared plugin classpath. Spotless works with 5.13 for this build. Remove once
+        // JReleaser supports JGit 7.
+        resolutionStrategy.force 'org.eclipse.jgit:org.eclipse.jgit:5.13.5.202508271544-r'
+    }
+}
+
 plugins {
     id 'com.gradleup.shadow' version '9.6.1'
     id 'com.github.spotbugs' version '6.5.13'