FastFileSystem - Unified file search engine with JNI bindings [ALPHA]

About

FastFileSystem is a high-performance Java file search engine that combines indexing, searching, and real-time file monitoring through JNI bindings to native C++ code. Designed for Java applications requiring Everything-style file search capabilities, it provides zero-copy memory-mapped access and incremental updates via USN Journal on Windows.

Tags: file-search, filesystem, indexing, mmap, usn-journal, jni, cpp, windows, autocomplete, fuzzy-search

Overview

FastFileSystem is a unified C++ module that encapsulates FastFileIndex, FastFileSearch, and FastFileWatch into a single API, along with JNI bindings for FastJava integration.

High-Level Architecture

Your three modules form a complete Everything-style file search engine:

• FastFileIndex - Full filesystem scan → produces a binary, mmap-capable index of all files.
• FastFileSearch - Builds Prefix Trie, N-Gram index, Exact Match map, and Ranking engine on top of the index.
• FastFileWatch - Uses USN Journal to keep the index + search structures live-updated with zero rescans.

This is exactly the architecture used by Everything, Spotlight, VSCode, and fsearch — but modular and embeddable.

Features

• Unified C++ module encapsulating Index + Search + Watch
• Full mmap-based index access (no std::vector primary structure)
• JNI bindings with zero-copy (DirectByteBuffer + Offsets instead of String[])
• Java reads directly from mmap without copies
• Minimalistic, modular, high-performance
• Zero overhead, no copies, no GC stress
• Hot-reload capable (double mmap buffer + atomic pointer swap)

Combined System Summary

You now have:

• A full filesystem indexer
• A binary, mmap-capable index format
• A high-performance autocomplete engine
• A substring + fuzzy search engine
• A ranking engine
• A real-time file watcher with USN Journal
• A fully incremental search system with zero rescans
• JNI bindings for FastJava
• Unified C++ API

This is a complete, production-grade file search engine — modular, embeddable, and faster than most existing tools.

Installation

Building from Source

git clone https://github.com/andrestubbe/FastFileSystem.git
cd FastFileSystem
mkdir build && cd build
cmake ..
cmake --build .

Usage

C++ API

#include "FastFileSystem.hpp"

FastFileSystem fs;
fs.build({"C:\\"});

std::vector<FileEntry> results;
fs.search("query", 100, results);

fs.recordOpen(results[0].id);

Java API (JNI)

FastFileSystem fs = new FastFileSystem();
fs.loadIndex("files.idx");

SearchResult[] results = fs.search("fast", 64);

for (SearchResult result : results) {
    System.out.println(result.path);
}

fs.close();

Platform Support

• Windows 10+ (x86_64) - Fully supported with native implementation
• Linux - Planned
• macOS - Planned

License

This project is licensed under the MIT License - see the LICENSE file for details.

Related Projects

• FastFileIndex - Binary file indexing with mmap support
• FastFileSearch - Prefix Trie, N-Gram index, and Ranking engine
• FastFileWatch - USN Journal-based live file monitoring
• FastCore - Unified JNI loader and platform abstraction