upgrade-gradle-9

name: upgrade-gradle-9 description: > Upgrade from Gradle 8.x to Gradle 9.x with plugin compatibility updates. Required for Java 25 support. Includes plugin version mappings and migration patterns. compatibility: Java projects using Gradle 8.x metadata: version: "2.0.0" technology: java category: modernization tags: - gradle - gradle-9 - build - plugins - upgrade

Upgrade Gradle 9

Upgrade from Gradle 8.x to Gradle 9.x with all required plugin updates.

When to Use

• Recommended for all projects - Gradle 9.3.1 is now the standard
• Upgrading to Java 25 (requires Gradle 9.x)
• Need Gradle 9 features
• Current Gradle 8.x plugins are deprecated
• When asked to "prepare for Gradle 9"

Skill Contents

Sections

• When to Use
• Target Versions
• Quick Start
• References
• Plugin Migration Details
• Related Skills

Available Resources

📚 references/ - Detailed documentation

• plugin compatibility

Target Versions

Quick Start

1. Update Gradle Wrapper

./gradlew wrapper --gradle-version=9.3.1

2. Update Plugin Versions

# gradle/libs.versions.toml
[plugins]
lombok = "io.freefair.lombok:9.2.0"
spotless = "com.diffplug.spotless:8.2.1"
sonarqube = "org.sonarqube:7.2.2.6593"
protobuf = "com.google.protobuf:0.9.6"
bitso-develocity = { id = "bitso.develocity", version = "0.2.8" }

// settings.gradle - use version catalog alias
plugins {
    alias(libs.plugins.bitso.develocity)  // Bitso wrapper plugin, not upstream com.gradle.develocity
}

3. Add JUnit Platform Launcher

Required for JUnit 5.11+ with Gradle 9:

subprojects {
    plugins.withType(JavaPlugin).configureEach {
        dependencies {
            testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
        }
    }
}

4. Validate

./gradlew clean build test

References

Plugin Migration Details

Lombok Plugin (Freefair)

# Old (Gradle 8.x)
lombok = "io.freefair.lombok:8.14.2"

# New (Gradle 9.x)
lombok = "io.freefair.lombok:9.2.0"

Requires Lombok 1.18.42 for Java 25 bytecode support:

lombok {
    version = libs.versions.lombok.get()  // 1.18.42
}

Spotless

# Old (Gradle 8.x)
spotless = "com.diffplug.spotless:6.x"

# New (Gradle 9.x)
spotless = "com.diffplug.spotless:8.2.1"

For Java 25 formatting, use palantir-java-format 2.74.0.

SonarQube

# Old (Gradle 8.x)
sonarqube = "org.sonarqube:6.x"

# New (Gradle 9.x)
sonarqube = "org.sonarqube:7.2.2.6593"

Related Skills