I Built JavaLens: A Desktop Visualizer for Java Runtime Execution

Hey everyone! 👋

I've been working on a project called JavaLens, a desktop application designed to make Java program execution easier to understand by visualizing what's happening at runtime.

When learning or debugging Java, reading the code is only part of the picture. Understanding how variables change, how function calls interact, and how objects and arrays occupy memory can be challenging when everything is represented only as text.

That's the problem I wanted to explore with JavaLens.

🔍 What is JavaLens?

JavaLens is a desktop application that helps visualize Java program execution, including:

Scopes and variables — inspect program state during execution.
Heap and objects — visualize objects and their relationships in memory.
Function calls — follow execution as methods are called.
Arrays and data structures — get a visual perspective on runtime state.
Integrated terminal — work with Java programs inside the application.

The goal is to make runtime behavior more observable and easier to follow, especially when learning how Java works internally.

🛠️ How I built it

JavaLens uses a combination of technologies:

React for the user interface.
Rust and Tauri for the desktop application and backend.
Java Debug Interface (JDI) to inspect Java execution.

One of the interesting parts of this project is connecting the Java execution process to a visual representation of its runtime state.

🚧 Current status

JavaLens is still under development. There are things to improve, features to refine, and edge cases to handle.

I'm sharing it now because feedback from other developers can help me identify what works, what doesn't, and what would make the tool genuinely useful.

💬 I'd love your feedback!

A few things I'd especially appreciate feedback on:

What would you want to see in a Java runtime visualizer?
Which runtime details are most difficult to understand when learning Java?
What features would make a tool like this useful for debugging or teaching?
If you're interested in contributing, suggestions and pull requests are welcome!