Maven

🧾 What is Maven?

Maven is a free, open-source, and build automation tool primarily used for Java projects. It simplifies project build, dependency management, and documentation with a standardized project structure.

🔧 In Simple Terms

Maven helps you compile code, manage dependencies, run tests, and package applications — all using a single configuration file (pom.xml).

🧠 Key Features of Maven

Feature	Description
✅ Dependency Management	Automatically downloads and manages required libraries (JARs).
⏳ Standardization	Provides a consistent project structure across teams.
🧪 Build Lifecycle	Defines phases like compile, test, package, install, and deploy.
⚡ Plugin System	Uses plugins to extend functionality (testing, reporting, deployment).
🔗 Integration	Works well with CI/CD tools like Jenkins, GitLab CI, and GitHub Actions.

📦 Maven vs Gradle

Maven	Gradle
XML-based configuration (`pom.xml`)	Groovy/Kotlin DSL-based configuration
Convention over configuration	More flexibility, faster builds
Mature, widely adopted	Newer, modern, and optimized for performance

📂 Real-World Analogy

Imagine building a house:

Maven is like the construction manager who follows a blueprint (pom.xml).
It fetches materials (dependencies) automatically when needed.
It ensures each phase (foundation, walls, painting) happens in the right order.

💻 Common Maven Commands

Command	Purpose
`mvn clean`	Removes previously compiled files
`mvn compile`	Compiles the source code
`mvn test`	Runs the test cases
`mvn package`	Packages the code into JAR/WAR file
`mvn install`	Installs package into local repository
`mvn deploy`	Deploys package to remote repository
`mvn dependency:tree`	Displays dependency hierarchy

🧑‍🤝‍🧑 Who Uses Maven?

Java Developers
DevOps Engineers
QA/Test Engineers
Build & Release Engineers

📅 Maven 10-Day Training Plan (DevOps-Oriented)

🔹 Day 1: Maven Basics & Setup

Introduction to Maven in DevOps context
Install Maven on Linux (RHEL/Ubuntu) & Windows
Configure environment variables (JAVA_HOME, MAVEN_HOME)
Hands-on: Create a simple Maven project using archetype

🔹 Day 2: POM & Build Lifecycle

Deep dive into pom.xml
GAV (GroupId, ArtifactId, Version) explained
Maven build lifecycle (validate → compile → test → package → install → deploy)
Hands-on: Run mvn clean install and observe lifecycle phases

🔹 Day 3: Dependency Management

Understanding repositories (local, central, remote)
Dependency scopes (compile, provided, runtime, test)
Hands-on: Add logging and testing dependencies
Managing transitive dependencies
Introduction to OWASP Dependency-Check Plugin (security scanning)

🔹 Day 4: Maven Plugins in Depth

What are plugins? Why they matter in DevOps
Common plugins:
- Compiler
- Surefire (unit testing)
- Failsafe (integration testing)
- Shade (fat JAR)
Hands-on: Configure plugins in pom.xml
Automating builds with plugins

🔹 Day 5: Nexus Repository Integration

Introduction to Nexus/Artifactory in CI/CD
Configuring settings.xml for private repository
Deploying artifacts to Nexus using mvn deploy
Hands-on: Setup Maven to publish to a Nexus repository

🔹 Day 6: SonarQube Integration

Why code quality & static analysis matter in DevOps
Installing/configuring SonarQube
Sonar Maven plugin
Hands-on: Analyze a Maven project with SonarQube
Automating SonarQube scans in CI/CD pipeline

🔹 Day 7: Tomcat Deployment

Introduction to application deployment with Tomcat
Tomcat Maven Plugin overview
Hands-on: Deploy a WAR file to local Tomcat using Maven
Automating deployment process with profiles

🔹 Day 8: Build Profiles & Multi-Module Projects

Creating environment-specific build profiles (dev, test, prod)
Activating profiles in CI/CD
Hands-on: Multi-module Maven project (API + Service + UI)
Using profiles for environment-specific deployments

🔹 Day 9: GitLab CI/CD with Maven

Integrating Maven builds into GitLab pipelines
Writing .gitlab-ci.yml for build → test → package → deploy stages
Pushing build artifacts to Nexus from GitLab
Hands-on: End-to-end GitLab CI/CD pipeline for a Maven project

🔹 Day 10: Advanced DevOps Practices

Dependency checks & vulnerability management
Generating SBOM (Software Bill of Materials) with Maven
Versioning strategies (SNAPSHOT vs Release builds)
Artifact promotion (Dev → Test → Prod)
Final Hands-on:
- Build → Test → Code Scan (SonarQube + Dependency-Check)
- Publish artifact to Nexus
- Deploy to Tomcat
- Run pipeline in GitLab CI/CD

✅ Outcome (DevOps-Focused)
By the end of Day 10, you will be able to:

Automate Maven builds in GitLab pipelines
Scan dependencies for vulnerabilities (OWASP Dependency-Check)
Perform code quality checks with SonarQube
Deploy artifacts to Tomcat automatically
Manage and promote artifacts using Nexus/Artifactory
Build a complete DevOps-ready Maven CI/CD pipeline