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

Skill Contents

Sections

• When to Use (L22-L28)
• Target Versions (L48-L60)
• Quick Start (L61-L107)
• References (L108-L113)
• Plugin Migration Details (L114-L155)
• Related Skills (L156-L160)
• Related Commands (L161-L167)

Available Resources

📚 references/ - Detailed documentation

• plugin compatibility

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Target Versions

Component	Gradle 8.x	Gradle 9.x	Notes
Gradle	8.14.3	9.2.1	Recommended for all projects
Lombok Plugin	8.14.2	9.2.0	Freefair for Gradle 9.2.1
Spotless	6.x	8.1.0	Major bump
SonarQube	6.x	7.2.2.6593	Major bump
Develocity	0.1.x	0.2.8	Compatibility
Flyway	10.x	11.19.0	If used
jOOQ	9.x	10.1.1	If used
Protobuf	0.9.x	0.9.6	Gradle 9 compatible

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

Reference	Content
references/plugin-compatibility.md	Plugin version mappings and known issues

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

Related Commands

This skill is referenced by:

• /prepare-to-gradle-9 - Prepare for Gradle 9 upgrade
• /prepare-to-java-25 - Java 25 preparation (requires Gradle 9)