tooling-java-generator_skill

Overview

This skill generates production-ready Java project scaffolding with modern tooling and sensible defaults. It supports Maven or Gradle, JUnit 5 + Mockito testing, Checkstyle/SpotBugs quality checks, and packaging options including JAR/WAR and GraalVM native images. The generator targets Java 11, 17, or 21 and produces syntactically valid build files, example code, and CI/CD templates. Outputs include a JSON contract describing directory layout, file contents, commands, and a normalized timestamp.

How this skill works

Given validated inputs (project_type, build_tool, java_version, project_name), the skill creates a standard directory structure and populates build files (pom.xml or build.gradle) with pinned dependency versions and tool plugin configurations. For extended mode it adds testing (JUnit 5, Mockito), code quality tools (Checkstyle, SpotBugs, optional PMD), and CI/CD artifacts (GitHub Actions, Dockerfile). For packaging it configures executable/fat JARs or WARs, multi-module parents, and optional GraalVM native-image support with necessary reflection/resource configs.

When to use it

• Bootstrapping a new Java library, application, Spring Boot service, or microservice using Java 11/17/21
• Migrating legacy projects to modern build tooling and standardized configuration
• Creating multi-module enterprise projects with centralized dependency management
• Setting up testing and static analysis pipelines for reliable CI builds
• Packaging applications for containerized deployment or GraalVM native images

Best practices

• Validate project_name as a lowercase Java package-like identifier; abort on invalid names
• Choose Maven for strict dependency management and enterprise environments; choose Gradle for flexible, performant builds
• Pin test and plugin versions explicitly; use version catalogs for multi-module Gradle projects
• Include .gitignore entries for build outputs, IDE files, and sensitive artifacts
• Use Testcontainers for integration tests and multi-stage Dockerfiles for secure images

Example use cases

• Library: generate JAR layout, example utility class, JUnit 5 tests, and publishing-ready POM
• Application: executable fat JAR with main class, CLI example, and GitHub Actions workflow
• Spring Boot API: starter parent POM, sample controller, health checks, and Dockerfile
• Microservice: Spring Boot + Docker + observability hooks, Testcontainers integration tests
• Enterprise multi-module: parent POM/Gradle settings, api/core/service modules, and reactor build