Upgrade Java 25

Upgrade Java projects to Java 25 with all required dependency updates.

When to Use

• Project needs to upgrade from Java 21 to Java 25
• Need features from Java 25 (records, pattern matching improvements, etc.)
• Planning to stay on latest LTS-adjacent releases
• When asked to "prepare for Java 25" or "upgrade to Java 25"

Skill Contents

Sections

• When to Use
• Prerequisites
• Target Versions
• ⚠️ DO NOT Upgrade
• Workflow
• Version Catalog Updates
• Java Toolchain Configuration
• ⚠️ Critical: Do NOT Use groovy-all
• Override Spring Boot's Groovy Version
• References
• Related Skills

Available Resources

📚 references/ - Detailed documentation

• preparation

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Prerequisites

1. Spring Boot 3.5.x - Upgrade to Spring Boot 3.5.x first
2. sdkman - For managing Java versions
3. Java 25 Temurin - Install via: sdk install java 25.0.1-tem

Target Versions

Component	Version	Notes
Java	25	Target JDK
Gradle	9.2.1	Major version required
Groovy	5.0.3	Java 25 requires Groovy 5.x
Spock	2.4-groovy-5.0	Must match Groovy version
Lombok	1.18.42	Java 25 bytecode support
Lombok Plugin	9.2.0	Freefair plugin for Gradle 9.2.1
Spotless	8.1.0	Gradle 9 compatible
SonarQube Plugin	7.2.2.6593	Gradle 9 compatible
ByteBuddy	1.17.5+	ASM 9.8 for Java 25

⚠️ DO NOT Upgrade

• protobuf: Keep existing version
• grpc: Keep existing version
• Spring Boot: Keep at 3.5.x (already upgraded)

Workflow

Phase 1: Prepare (Local Validation)

# Install and use Java 25
sdk install java 25.0.1-tem
sdk use java 25.0.1-tem

# Upgrade Gradle wrapper
./gradlew wrapper --gradle-version=9.2.1

# Update version catalog (see below)
# Build and test locally
./gradlew clean build test

Phase 2: Commit (After Tests Pass)

Only commit the toolchain change after all tests pass locally.

Version Catalog Updates

# gradle/libs.versions.toml
[versions]
groovy = "5.0.3"
spock = "2.4-groovy-5.0"
lombok = "1.18.42"
bytebuddy = "1.17.5"  # If defined

[plugins]
lombok = "io.freefair.lombok:9.2.0"
spotless = "com.diffplug.spotless:8.1.0"
sonarqube = "org.sonarqube:7.2.2.6593"

Java Toolchain Configuration

// root build.gradle
allprojects {
    plugins.withType(JavaPlugin).configureEach {
        java {
            toolchain {
                languageVersion = JavaLanguageVersion.of(25)
                vendor = JvmVendorSpec.ADOPTIUM
            }
        }
    }
}

⚠️ Critical: Do NOT Use groovy-all

The groovy-all:5.0.3 artifact has broken transitive dependencies:

// ❌ NEVER: groovy-all has broken transitive deps
testImplementation 'org.apache.groovy:groovy-all:5.0.3'

// ✅ CORRECT: Let spock-core bring in Groovy 5.0.3 transitively
testImplementation libs.spock.core
testImplementation libs.spock.spring  // if using Spring

Override Spring Boot's Groovy Version

// root build.gradle
allprojects {
    ext['groovy.version'] = libs.versions.groovy.get()
}

References

Reference	Content
references/preparation.md	Detailed preparation steps and prerequisites

Related Skills

Skill	Purpose
upgrade-spring-boot-3-5	Must upgrade first
upgrade-gradle-9	Gradle 9 upgrade patterns