Gradle 9 Upgrade

Gradle 9 Upgrade

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

When to Use

• Recommended for all projects - Gradle 9.2.1 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

Available Resources

📚 references/​ - Detailed documentation

• plugin compatibility

---

Target Versions

Quick Start

1. Update Gradle Wrapper

./​gradlew wrapper --gradle-version=9.2.1

2. Update Plugin Versions

# gradle/​libs.versions.toml
[plugins]
lombok = "io.freefair.lombok:9.2.0"
spotless = "com.diffplug.spotless:8.1.0"
sonarqube = "org.sonarqube:7.2.2.6593"
protobuf = "com.google.protobuf:0.9.6"

// settings.gradle
plugins {
    id 'bitso.develocity' version "${develocityPluginVersion}"  // 0.2.8
    id 'org.sonarqube' version "${sonarqubePluginVersion}"      // 7.2.2.6593
}

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:8.1.0"

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

• spring-boot-3-5 - Upgrade Spring Boot first
• java-25 - Java 25 requires Gradle 9

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