Spring: Bean lifecycle callbacks with @PostConstruct and @PreDestroy

@Component
class ConnectionPool {

    @PostConstruct
    void open() { System.out.println("pool opened"); }

    @PreDestroy
    void close() { System.out.println("pool closed"); }
}

pool opened      <- after the constructor AND after injection
... application runs ...
pool closed      <- on graceful shutdown only (not on kill -9)