AVL Tree Visualizer

An educational Java/Swing GUI that animates every AVL rotation frame by frame, at whatever speed keeps a confused Data Structures student from crying — adjustable, no judgment.

Trail statsTelemetry · at a glance

4
rotation types, each animated step by step
3
traversal orders shown beside the tree: pre-, in- and post-order
0
external dependencies

01 · The Map · Mission Brief

Brief

Every CS student learns the same way that AVL trees "self-balance," and almost none of them see it actually happen — the textbook shows a before-and-after diagram and expects you to believe the rotation in between. AVL Tree Visualizer is my objection to that. It's a small Swing desktop app that makes self-balancing binary search trees tangible instead of abstract: keys are inserted one at a time, and whenever a rotation is needed to restore balance, the GUI animates it rather than just redrawing the final tree, so you can actually watch an LL, RR, LR, or RL rotation happen.

Don’t take my word for it — the receipts are on GitHub

02 · The Pack · Crew Duties

My Contribution

Implemented the AVL tree itself — AVLNode, AVLTree, and the interface separating the data structure from the GUI — including all four rotation cases.
Built AVLTreeVisualizer to render the current tree state (nodes, edges, and balance factors) and animate transitions between states at a user-selectable speed (Slow / Normal / Fast).
Added pre-order, in-order, and post-order traversal output alongside the tree view, and a detailed log of every rotation performed during an insertion.
Made the demo key sequence configurable in AVLTreeDemo, and added a restart control so a session can be replayed without relaunching the app.

03 · In Bloom · Bright Stars

Key Features

Animated rotations

Every LL, RR, LR, and RL rotation is animated, not just redrawn — the point of the whole project is making the mechanism visible.

Adjustable speed

Playback speed (Slow / Normal / Fast) can be changed mid-run to slow down and study a specific rotation.

Traversal output

Pre-order, in-order, and post-order results update live alongside the visual tree.

No external dependencies

Pure Java + Swing — just a recent JDK (22 or newer) is enough to compile and run it.

04 · Sunrise · Planet-rise

Takeaways

Building the animator forced me to be precise about exactly where every node starts and ends up for each of the four rotation cases — a level of precision that's suspiciously easy to skip when you already "understand" the algorithm on paper. I've since used this exact tool, unprompted, to win a whiteboard argument about AVL rotations. Worth the weekend.

Previous waypointPrevious burn · 6 of 10

Newton-Gravity

Newton’s apple, from-scratch OpenGL physics

Next waypointNext burn · 8 of 10

Student Attendance Management System

Role-based attendance management in Django

All Projects