Search Engine — Iteration 1

A local file search engine built for the Software Design 2026 course at TU Cluj-Napoca. Indexes files on your device and provides fast, full-text search through both a GUI and a CLI.

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Features

• Recursive file traversal with symlink loop detection
• Full-text search via SQLite FTS5 with BM25 ranking
• Incremental indexing — only re-indexes files that have changed
• File previews — first 3 non-blank lines of text files shown in results
• Extension and directory filters — narrow results by file type or path
• Live search — results appear as you type (GUI)
• Dual interface — JavaFX GUI and interactive CLI
• Runtime configuration — root directory, database path, report format
• JSON and TEXT report formats (CLI)
• Stale entry cleanup — removes index entries for deleted files

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Tech Stack

Layer	Technology
Language	Java 17
Build	Maven
Database	SQLite + FTS5 (xerial/sqlite-jdbc 3.45.1.0)
GUI	JavaFX 17.0.2 + AtlantaFX NordDark
Formatting	Spotless + Google Java Format

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Project Structure

src/main/java/app/
├── Main.java                  — CLI composition root
├── cli/
│   └── CLI.java               — interactive CLI
├── config/
│   └── IndexConfig.java       — runtime configuration
├── db/
│   ├── Database.java          — connection, WAL mode, schema
│   └── FileRepository.java    — all SQL queries
├── gui/
│   ├── MainApp.java           — JavaFX entry point
│   └── SearchController.java  — FXML controller
├── indexer/
│   ├── FileFilter.java        — directory and extension filtering
│   ├── FileIndexer.java       — traversal and indexing
│   └── IndexerFactory.java    — creates FileIndexer instances
├── model/
│   ├── FileRecord.java
│   ├── IndexReport.java
│   ├── SearchResult.java
│   └── TraversalStats.java
├── processor/
│   └── ContentExtractor.java  — extracts text content and previews
├── search/
│   ├── SearchEngine.java
│   ├── SearchRequest.java
│   ├── SearchRequestParser.java
│   └── SearchScope.java
└── util/
    └── FileTypes.java         — text extension registry

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Running the Project

GUI

mvn javafx:run

1. Enter or browse to a directory
2. Click Index — live progress shown in status bar
3. Type in the search bar — results appear as you type
4. Use the extension dropdown or directory field to filter results
5. Click a result to preview it

CLI

In IntelliJ, create a run configuration:

• Main class: app.Main
• Program arguments: <directory> [database] [TEXT|JSON]

Or via Maven:

mvn compile exec:java -Dexec.mainClass="app.Main" -Dexec.args="D:\YourDirectory"

On startup the CLI will prompt:

Directory to index (default: C:\Users\...):
Report format [TEXT/JSON] (default TEXT):

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Search Syntax

Syntax	Example	Description
keyword	main	Full-text search
multi-word	public static void	Multi-word FTS5 search
extension filter	main ext:java	Filter by file extension
directory filter	config dir:D:\src	Filter by directory path
combined	main ext:java dir:D:\src	All filters together

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Database Schema

CREATE TABLE files (
    path         TEXT PRIMARY KEY,
    name         TEXT NOT NULL,
    extension    TEXT,
    sizeBytes    INTEGER NOT NULL,
    lastModified INTEGER NOT NULL,
    preview      TEXT
);

CREATE VIRTUAL TABLE files_fts USING fts5(
    path UNINDEXED,
    name,
    content
);

WAL journal mode is enabled for concurrent CLI and GUI access.

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Ignored by Default

Directories: .git, node_modules, target, build, cache, dist, AppData, flutter, scoop

Extensions: class, obj, o, zip, tar, gz, rar, 7z, tmp, bak, lnk, db, sqlite

All other file types are indexed by metadata. Text files additionally have their content indexed for full-text search.

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Architecture

See ARCHITECTURE.md for the full C4 model covering system context, containers, components, and runtime sequence diagrams.