{"id":35408649,"url":"https://github.com/flintvn/flintespjvm","last_synced_at":"2026-04-05T09:01:26.358Z","repository":{"id":250158587,"uuid":"833637428","full_name":"FlintVN/FlintESPJVM","owner":"FlintVN","description":"FlintESPJVM brings the power of Java to ESP32.  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This enables running and debugging JVM-based languages such as Java, Kotlin, Scala, Groovy, Clojure, JRuby, and Jython on ESP32 hardware.\r\n\r\n![demo](images/demo1.avif)\r\n## Key Features\r\n- Supports most Java bytecode instructions.\r\n- Supports debugging with [FlintJVM Debug](https://marketplace.visualstudio.com/items?itemName=ElectricThanhTung.flintjvm-debugger) VS Code extension via serial port.\r\n## How to use\r\n### 1. Supported Boards\r\nFlintESPJVM is compatible with a variety of ESP32 boards, including:\r\n  | Board             | Cores                     | Flash | SRAM  | PSRAM |\r\n  | ----------------- | ------------------------- | ----- | ----- | ----- |\r\n  | **Generic ESP32** | 240MHz Xtensa Dual-core   | 4MB   | 520KB | ❌    |\r\n  | **ESP32-C3FH4**   | 160MHz RISC-V Single-core | 4MB   | 400KB | ❌    |\r\n  | **ESP32-C6FH4**   | 160MHz RISC-V Single-core | 4MB   | 512KB | ❌    |\r\n  | **ESP32-C6FH8**   | 160MHz RISC-V Single-core | 8MB   | 512KB | ❌    |\r\n  | **ESP32-S2FN4R2** | 240MHz Xtensa Single-core | 4MB   | 320KB | 2MB   |\r\n  | **ESP32-S3FH4R2** | 240MHz Xtensa Dual-core   | 4MB   | 512KB | 2MB   |\r\n  | **ESP32-S3N4RX**  | 240MHz Xtensa Dual-core   | 4MB   | 512KB | ✅    |\r\n  | **ESP32-S3N8RX**  | 240MHz Xtensa Dual-core   | 8MB   | 512KB | ✅    |\r\n  | **ESP32-S3N16RX** | 240MHz Xtensa Dual-core   | 16MB  | 512KB | ✅    |\r\n### 2. Flashing the Firmware\r\nTo get FlintESPJVM up and running on your board:\r\n- Quick Flash: Use the [ESP Web Tool](https://esp.flint.vn) for an easy, browser-based flashing experience.\r\n- Manual Build: Prefer building it yourself? Utilize the ESP-IDF framework to compile and flash the project manually.\r\n### 3. Building Java Projects for FlintESPJVM\r\nTo develop Java applications for FlintESPJVM:\r\n- Project Setup: Use the [FlintJDK](https://github.com/FlintVN/FlintJDK) module to access core Java libraries compatible with FlintJVM.\r\n- Debugging: Install the FlintJVM Debug extension in VS Code.\r\n\r\nRefer to the [FlintExample](https://github.com/FlintVN/FlintExample) project, which provides a simple and clear template to help you get started with building Java apps for FlintJVM.\r\n### 4. Dependencies and Cloning\r\n- This project requires ESP-IDF v5.5.0 or later to build.\r\n- Run the following command to clone this repository and include all dependent submodules:\r\n```sh\r\n\u003e git clone --recurse-submodules https://github.com/FlintVN/FlintESPJVM.git\r\n```\r\n## Benchmark\r\nBelow are the performance benchmarks of several different programming languages on the ESP32, focusing on.\r\n- Execution time of 10 million iterations using `for` and `while` loops.\r\n- Maximum toggling frequency of GPIO when driven by the CPU.\r\n\r\n  | Language      | Platform              | `for` loop (10M) | `while` loop (10M) | GPIO toggle frequency |\r\n  | ------------- | --------------------- | ---------------- | ------------------ | --------------------- |\r\n  | C             | IDF v5.5.0            | 375 ms           | 375 ms             | 2.2 MHz               |\r\n  | Java          | FlintJVM v1.1.7       | 9254 ms          | 9254 ms            | 295 KHz               |\r\n  | MicroPython   | MicroPython v1.26.0   | 43677 ms         | 79582 ms           | 107 KHz               |\r\n  | C#            | NanoFramework v1.12.4 | 77656 ms         | 77660 ms           | 2.4 KHz               |\r\n\r\nThe source code of this test can be viewed at [ESP32-Perfomance](https://github.com/FlintVN/ESP32-Perfomance).\r\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fflintvn%2Fflintespjvm","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fflintvn%2Fflintespjvm","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fflintvn%2Fflintespjvm/lists"}