110-java-maven-best-practices

# Maven Best Practices Improve Maven POM configuration using industry-standard best practices. **What is covered in this Skill?** - Dependency management via `<dependencyManagement>` and BOMs - Standard directory layout (`src/main/java`, `src/test/java`) - Centralized plugin management - Build profiles for environment-specific settings - Readable POM structure with version properties - Explicit repository declaration - Version centralization - Multi-module project structure with proper inheritance - Cross-module version consistency - Multi-module scope: After reading the root `pom.xml`, check for a `<modules>` section. If present, read **every** child module's `pom.xml` before making any recommendations. - Check each child for hardcoded versions that duplicate parent `<dependencyManagement>`, redundant `<pluginManagement>` blocks, properties that should be centralized, and version drift across sibling modules. ## Constraints Before applying Maven best practices recommendations, ensure the project is in a valid state by running Maven validation. This helps identify any existing configuration issues that need to be resolved first. For multi-module projects, scope analysis must cover every child module POM — not just the root. - **MANDATORY**: Run `./mvnw validate` or `mvn validate` before applying any Maven best practices recommendations - **VERIFY**: Ensure all validation errors are resolved before proceeding with POM modifications - **SAFETY**: If validation fails, do not continue and ask the user to fix the issues before continuing - **MULTI-MODULE DISCOVERY**: After reading the root `pom.xml`, check whether it contains a `<modules>` section. If it does, read every child module's `pom.xml` before making any recommendations — analysis scope is the full module tree, not only the root - **CROSS-MODULE SCOPE**: When child modules exist, check each one for: hardcoded dependency versions that duplicate `<dependencyManagement>` in the parent, plugin configurations that duplicate `<pluginManagement>`, properties that should be centralized in the parent, and version drift (same artifact declared at different versions across sibling modules) - **BEFORE APPLYING**: Read the reference for detailed examples, good/bad patterns, and constraints ## When to use this skill - Review pom.xml to improve it - Apply Maven best practices to pom.xml - Improve Maven POM configuration ## Workflow 1. **Validate project before recommendations** Run `./mvnw validate` or `mvn validate` and stop if validation fails. 2. **Read reference and analyze root POM** Read `references/110-java-maven-best-practices.md`, then inspect root `pom.xml` structure, dependency management, plugin management, properties, and profiles. 3. **Expand to full module tree when present** If root has a `<modules>` section, read every child `pom.xml` and evaluate cross-module duplication, centralization opportunities, and version drift. 4. **Provide prioritized best-practice recommendations** Propose concrete, safe improvements aligned with Maven best practices and full-module findings. ## Reference For detailed guidance, examples, and constraints, see [references/110-java-maven-best-practices.md](references/110-java-maven-best-practices.md).