packagraph2

An interactive Java package dependency browser and visualizer. Point it at any Java codebase and get a live, explorable graph of how your packages depend on each other — no compilation or build system required.

(Using packagraph2 into packagraph2's source code: packagraph2.pg2 project)

AI Development Disclaimer

This project is a proof of concept exploring what AI-assisted development can achieve. It is the spiritual successor to packagraph, which was manually developed with a full test suite covering all important parts.

packagraph2 was built almost entirely with AI (Claude) in roughly 1.5 days — from zero to a fully functional interactive web UI with features the original never had (live graph editing, undo/redo, categories, comments, export to multiple formats, git clone support, etc.).

The most striking difference is in testing: the original packagraph has automated tests for its core logic because a human developer needs that safety net to refactor and evolve the code with confidence. This version has no tests — when the AI writes the code, it can re-read, understand, and regenerate any part of the system on demand. Whether that trade-off holds up long-term is the question this project helps explore.

Features

• Zero setup analysis — parses Java source files directly with JavaParser; no need to compile the project or configure a build tool
• Interactive web UI — pan, zoom, click, and right-click your way through the dependency graph rendered via Graphviz (viz.js/WASM)
• Grouping rules — collapse multiple packages into a single named node (e.g., org.springframework.** → "Spring")
• Hiding rules — hide irrelevant packages by pattern (e.g., java.**, lombok.**)
• Categories — color-code groups with user-defined categories and a color picker
• Edge details — click any edge to see exactly which classes cause that dependency
• Class inspector — right-click a package to see all its classes with kind (class/interface/enum/record/annotation) and scope
• Package comments — annotate any node with a comment, shown on hover
• Circular dependency detection — highlights cycles in red
• Transitive reduction — hide redundant edges implied by transitive dependencies
• Common prefix trimming — shorten com.myapp.service.user to service.user for readability
• Multi-module support — select which source directories to include
• Clone from Git — clone a remote repo (with optional branch) and analyze it directly
• Undo/Redo — full undo/redo for all rule and option changes
• Export — SVG, PNG, PNG @2x, DOT, and JSON
• Project files — save and load .pg2 project files to preserve your rules and configuration

Usage

# Open an existing project
java -jar packagraph2.jar serve --project myproject.pg2

# Start fresh — create a new project by pointing at a source directory
java -jar packagraph2.jar serve