Spring Boot Deployment and Usage Guide

Prerequisites

• Java Development Kit (JDK) 17 or 21 (Spring Boot 3.x requires Java 17 as a baseline)
• Apache Maven 3.9.0+ (or use the provided Maven Wrapper ./mvnw)
• Git 2.20+
• Docker (optional, required for integration tests with Kafka, Redis, and other external services)
• System Resources: Minimum 4GB RAM available for the build process (8GB recommended)

Installation

Clone the repository and checkout the desired branch:

git clone https://github.com/spring-projects/spring-boot.git
cd spring-boot
git checkout main  # or specific version tag (e.g., v3.2.0)

Verify your environment:

./mvnw -version

Configuration

Maven Memory Settings

Set environment variables to prevent OutOfMemoryError during builds:

export MAVEN_OPTS="-Xmx2g -XX:MaxMetaspaceSize=512m -XX:+HeapDumpOnOutOfMemoryError"

Or create .mvn/jvm.config in the project root:

-Xmx2g
-XX:MaxMetaspaceSize=512m

Integration Test Configuration

For Kafka integration tests (as seen in KafkaProperties.java), configure external services via environment variables:

export SPRING_KAFKA_BOOTSTRAP_SERVERS=localhost:9092

Or rely on Testcontainers (requires Docker running) which auto-starts Kafka, Redis, and other services during tests.

Proxy Settings (Corporate Environments)

Configure ~/.m2/settings.xml for proxy access:

<settings>
  <proxies>
    <proxy>
      <id>corporate-proxy</id>
      <active>true</active>
      <protocol>http</protocol>
      <host>proxy.company.com</host>
      <port>8080</port>
    </proxy>
  </proxies>
</settings>

Build & Run

Full Build

Build the entire framework including tests:

./mvnw clean install

Quick Build (Development)

Skip tests and checks for faster iteration:

./mvnw clean install -DskipTests -Dcheckstyle.skip -T 4

Build Specific Modules

Build only the core module and its dependencies:

./mvnw clean install -pl spring-boot-project/spring-boot -am

Run Sample Applications

Navigate to a sample project and run:

cd spring-boot-samples/spring-boot-sample-simple
../../mvnw spring-boot:run

Or build and run the JAR:

../../mvnw clean package
java -jar target/spring-boot-sample-simple-*.jar

Running Tests

Run unit tests only (skips integration tests requiring Docker):

./mvnw test -Dtest=!*IntegrationTests

Run specific integration tests:

./mvnw test -pl spring-boot-project/spring-boot-autoconfigure -Dtest=KafkaAutoConfigurationTests

Deployment

Local Maven Repository

After mvn install, artifacts are available in ~/.m2/repository/org/springframework/boot/. Use them in your projects by referencing the SNAPSHOT version:

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>3.3.0-SNAPSHOT</version>
</parent>

Deploying Applications Built with Spring Boot

Package your application as an executable JAR:

./mvnw clean package spring-boot:repackage
java -jar target/myapp.jar

Or deploy to cloud platforms:

• Cloud Foundry: cf push myapp -p target/myapp.jar
• Kubernetes: Use the Jib Maven plugin or build a container image:

  ./mvnw spring-boot:build-image -Dspring-boot.build-image.imageName=myapp:latest
  

Contributing Changes

1. Build locally: ./mvnw clean install
2. Verify code style: ./mvnw checkstyle:check
3. Run full integration tests: ./mvnw verify -Pit
4. Commit and push to your fork

Troubleshooting

OutOfMemoryError During Build

Increase heap space:

export MAVEN_OPTS="-Xmx4g -XX:MaxMetaspaceSize=1g"

Test Failures: "Connection Refused"

Ensure Docker is running for integration tests using Testcontainers. Alternatively, skip integration tests:

./mvnw install -DskipITs

Checkstyle Violations

Auto-format code before committing:

./mvnw spring-javaformat:apply

Port Conflicts in Tests

If ports 8080, 9092 (Kafka), or 6379 (Redis) are occupied, tests using Testcontainers will use random ports, but specific tests may fail. Set custom ports:

export SPRING_KAFKA_BOOTSTRAP_SERVERS=localhost:9093

Slow Builds

Enable parallel builds and skip non-essential checks:

./mvnw clean install -T 4 -DskipTests -Dcheckstyle.skip -Denforcer.skip

Dependency Resolution Issues

Force update of snapshots:

./mvnw clean install -U