import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

/**
 * The one place that knows how to reach the database (Slide 4).
 * Credentials come from environment variables, never from the source code.
 */
public final class DB {
    private static final String URL = System.getenv("DB_URL");
    private static final String USER = System.getenv("DB_USER");
    private static final String PASSWORD = System.getenv("DB_PASSWORD");

    private DB() { }

    public static Connection getConnection() throws SQLException {
        return DriverManager.getConnection(URL, USER, PASSWORD);
    }
}