☁️ Gradle + TeamCity Setup with Amazon Corretto JDK and IntelliJ IDEA

This guide covers:

• How to configure a Gradle multi-module project with IntelliJ IDEA
• How to build it in TeamCity using a custom Amazon Corretto JDK
• How to ensure your build is portable across environments (e.g., JDK 21 locally, JDK 17 on target)

---

🧱 Project Structure (Multi-module)

This example assumes a root project tqpro with multiple subprojects:

tqpro/
├── build.gradle.kts             ← Root build config
├── settings.gradle.kts          ← Includes all subprojects
├── gradle.properties            ← Shared properties (optional)
├── tqapi/                       ← Subproject (Java)
│   └── build.gradle.kts
├── tqapp/
│   └── build.gradle.kts
├── tqweb/                       ← Subproject (web/static assets)
│   └── build.gradle.kts

---

⚙️ IntelliJ IDEA Setup

1. Open the tqpro/ directory as the root project
2. IntelliJ will detect all modules based on settings.gradle.kts
3. Ensure each module's build.gradle.kts applies the proper plugin (e.g., java, application)
4. Run configurations can be set per module (e.g., tqapi) with proper classpaths
5. Gradle sync will manage all dependencies — do not modify module dependencies via Project Structure UI

---

🧰 Example Root settings.gradle.kts

rootProject.name = "tqpro"
include("tqapi", "tqapp", "tqweb")

---

🛠️ Installing Amazon Corretto JDK (Non-System)

On each TeamCity agent, install Corretto manually into a custom location:

mkdir -p /opt/corretto-17
wget https://corretto.aws/downloads/latest/amazon-corretto-17-x64-linux-jdk.tar.gz -O /tmp/corretto.tar.gz
tar -xzf /tmp/corretto.tar.gz -C /opt/corretto-17 --strip-components=1

---

🏗️ TeamCity Build Step Configuration

1. Open your build configuration
2. In the Gradle build step:
   • Runner type: Gradle
   • Use Gradle wrapper: ✅
   • JDK: Custom
   • Custom JDK path: /opt/corretto-17

✅ This ensures Gradle runs under JDK 17 even if the system JDK is 21

---

⚙️ Gradle Configuration for Toolchains (Optional)

You can force Java 17 compatibility using Gradle's toolchain support:

subprojects {
    plugins.withId("java") {
        extensions.configure<JavaPluginExtension>("java") {
            toolchain {
                languageVersion.set(JavaLanguageVersion.of(17))
            }
        }
    }
}

Do not specify vendor.set(JvmVendorSpec.AMAZON) unless you're manually managing JDK installation — Gradle does not support downloading Amazon Corretto automatically.

---

🧪 Debugging Java Setup

Add a task in your root build.gradle.kts:

tasks.register("debugJdk") {
    doLast {
        println("Java version: ${System.getProperty("java.version")}")
        println("Java home: ${System.getProperty("java.home")}")
    }
}

Then run:

./gradlew debugJdk

---

✅ Summary

Item	Description
System JDK (TeamCity agent)	Java 21 (default, for agent)
Build JDK (Gradle step)	Amazon Corretto 17 (custom path)
Gradle JDK selection	Set JDK in Gradle step to Custom
IntelliJ support	Full sync from root project, no manual facet changes
Toolchains	Optional, use languageVersion.set(JavaLanguageVersion.of(17))

---

📦 Optional Improvements

• Install multiple JDKs under /opt/jdks/ and parameterize jdkPath
• Script the Corretto installation during agent provisioning
• Enable JAR packaging and distribution with jar and copyDependencies tasks