gardel

A lightweight Java library for encoding and decoding common chess notations, including FEN (Forsyth–Edwards Notation), PGN (Portable Game Notation), and SAN (Standard Algebraic Notation).

Features

• FEN: Encode and decode Forsyth–Edwards Notation, a standard notation for describing a particular board position of a chess game.
• PGN: Encode and decode Portable Game Notation, a standard format for recording chess games.
• SAN: Encode and decode Standard Algebraic Notation, a notation for describing chess moves.

This library is designed to be non-intrusive, you can plug it into your existing chess engine or GUI without modifying your codebase.

Prerequisites

• Java 21 or higher
• Maven or Gradle for dependency management (optional)

Installation

To use gardel in your project, add the dependency to your pom.xml (for Maven) or build.gradle (for Gradle).

Maven

<dependency>
    <groupId>net.chesstango</groupId>
    <artifactId>gardel</artifactId>
    <version>1.0.3</version>
</dependency>

Gradle

implementation 'net.chesstango:gardel:1.0.3'

Usage

FEN

FEN.of() creates a FEN object from a string. Once you have a FEN object, you can export it using a PositionBuilder.

ASCIIBuilder

 ...
 FEN fen = FEN.of("rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1");

 // ACSIIBuilder is a class that implements the PositionBuilder interface
 ASCIIBuilder asciiBuilder = new ASCIIBuilder();

 // Export FEN to the ASCII builder
 fen.export(asciiBuilder);

 // Get the ASCII representation of the position
 String position = asciiBuilder.getPositionRepresentation();

 System.out.println(position);

Result:

   -------------------------------
 8| r | n | b | q | k | b | n | r |
   -------------------------------
 7| p | p | p | p | p | p | p | p |
   -------------------------------
 6|   |   |   |   |   |   |   |   |
   -------------------------------
 5|   |   |   |   |   |   |   |   |
   -------------------------------
 4|   |   |   |   |   |   |   |   |
   -------------------------------
 3|   |   |   |   |   |   |   |   |
   -------------------------------
 2| P | P | P | P | P | P | P | P |
   -------------------------------
 1| R | N | B | Q | K | B | N | R |
   -------------------------------
    a   b   c   d   e   f   g   h
 FEN: rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1

MirrorPositionBuilder

 ...
 FEN fen = FEN.of("4rr1k/pppb2bp/2q1n1p1/4p3/8/1BPPBN2/PP2QPP1/2KR3R w - - 8 20");

 MirrorPositionBuilder<FEN> mirrorChessPositionBuilder = new MirrorPositionBuilder<>(new FENBuilder());

 fen.export(mirrorChessPositionBuilder);

 FEN fenMirror = mirrorChessPositionBuilder.getPositionRepresentation();

 assertEquals("2kr3r/pp2qpp1/1bppbn2/8/4P3/2Q1N1P1/PPPB2BP/4RR1K b - - 8 20", fenMirror.toString());

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the BSD 3-Clause License - see the LICENSE file for details.