A terminal-based multiplayer battleship game built in Java, played over encrypted WebSocket connections.
Two players connect to a central server, deploy ships on a grid, and take turns firing at each other using various weapon types. Ships are placed randomly, and losing a ship means losing access to its unique weapon.
- Encrypted multiplayer — RSA key exchange + AES-encrypted game traffic over WebSockets
- 3 Game Modes — Blitz, Strike, and War Mode with different map sizes and fleet compositions
- Weapon variety — Different ship classes unlock different weapons (1×1, 1×3, plus-shaped, nuke)
- Cooldown system — Powerful weapons have turn-based cooldowns
- Terminal UI — Entire game runs in the terminal with ASCII grid rendering
- Java 21+
- Maven 3.8+
- Make (optional, for development convenience)
make syncor directly:
mvn clean installmake serverThe server starts on port 8025 and prints the LAN IP address clients can connect to.
In a separate terminal (can be on a different machine on the same network):
make clientYou will be prompted for:
- The server IP address (e.g.,
192.168.1.5orlocalhost) - Your username
Once two players are connected, the server initiates the game.
make test- Connection — Client connects to the server via WebSocket (
ws://<ip>:8025/websockets/battlegrid) - Handshake — Server sends its RSA public key → Client generates an AES key, encrypts it with the server's public key, and sends it back with a username → All further communication is AES-encrypted
- Lobby — Server waits for two players. Once both are connected, the server assigns a game mode (or uses a default) and generates randomized ship placements for both players
- Gameplay — Players take turns selecting a weapon and target coordinates. The server validates moves, resolves hits/misses/sinks, and broadcasts updated state
- End — Game ends when all ships of one player are sunk. The server announces the winner
| Mode | Grid Size | Ships | Match Length |
|---|---|---|---|
| Blitz | 8×8 | 3 | ~5 min |
| Strike | 12×12 | 5 | ~15 min |
| War | 16×16 | 7 | ~30 min |
| Ship Class | Size | Weapon | Pattern | Cooldown |
|---|---|---|---|---|
| Patrol Boat | 2 | Standard Shot | 1×1 single tile | None |
| Submarine | 3 | Standard Shot | 1×1 single tile | None |
| Destroyer | 3 | Line Barrage | 1×3 horizontal/vertical | 2 turn |
| Battleship | 4 | Cross Bomber | Plus shape (5 tiles) | 3 turn |
| Carrier | 5 | Nuke | 3×3 | 5 turns |
Every ship always has access to the basic 1×1 Standard Shot with no cooldown, ensuring a player can always fire even if all special weapons are on cooldown.