Database — Configuration

database.yml

# Master switch. Plugin runs without a database when false.
enabled: false

# Backend type: MYSQL or POSTGRESQL
type: MYSQL

host: localhost
port: 3306
database: minecraft
username: root
password: ""

pool:
  maximum-pool-size: 10
  connection-timeout-ms: 30000

# Extra JDBC driver properties (optional)
properties:
  useSSL: "false"
  characterEncoding: "utf8"

Keep database.yml out of version control when it contains real credentials. Add it to .gitignore.

DatabaseConfig

DatabaseConfig is a typed AbstractConfig wrapper over database.yml. It reads all connection settings and assembles a DatabaseCredentials record:

DatabaseConfig config = new DatabaseConfig(plugin);

boolean enabled     = config.enabled();
DatabaseType type   = config.type();           // MYSQL or POSTGRESQL
DatabaseCredentials creds = config.credentials();

DatabaseCredentials is an immutable record:

record DatabaseCredentials(
        String host,
        int port,
        String database,
        String username,
        String password,
        int maximumPoolSize,
        long connectionTimeoutMs,
        Map<String, String> properties)

DatabaseManager

DatabaseManager (a Service) wraps everything:

// Construction (in DatabaseModule.onEnable):
SchedulerService scheduler = service(SchedulerService.class);
DatabaseManager dbManager = new DatabaseManager(plugin, new DatabaseConfig(plugin), scheduler.asyncExecutor());
dbManager.start();    // connects + applies schema if enabled
provide(DatabaseManager.class, dbManager);

// Usage anywhere else:
DatabaseManager db = service(DatabaseManager.class);
Database database  = db.database();            // throws if disabled
Optional<Database> safe = db.optional();        // safe access
boolean active     = db.isEnabled();

DatabaseModule.onDisable() calls dbManager.close() to shut down the HikariCP pool gracefully.

Choosing pool size

Server size	Recommended maximum-pool-size
Development / single-node small server	5
Medium server (< 100 concurrent players)	10
Large server or shared DB	20+

HikariCP recommends: pool size = (number of CPU cores * 2) + disk spindles.