How can I abort Spring-Boot startup?

Question

I'm writing a Spring-Boot application to monitor a directory and process files that are being added to it. I register the directory with WatchService in a configuration class:

@Configuration
public class WatchServiceConfig {

    private static final Logger logger = LogManager.getLogger(WatchServiceConfig.class);

    @Value("${dirPath}")
    private String dirPath;

    @Bean
    public WatchService register() {
        WatchService watchService = null;

        try {
            watchService = FileSystems.getDefault().newWatchService();
            Paths.get(dirPath).register(watchService, ENTRY_CREATE);
            logger.info("Started watching \"{}\" directory ", dlsDirPath);
        } catch (IOException e) {
            logger.error("Failed to create WatchService for directory \"" + dirPath + "\"", e);
        }

        return watchService;
    }
}

I would like to abort Spring Boot startup gracefully if registering the directory fails. Does anybody know how I can do this?

Answer 1

The accepted answer is correct, but unnecessarily complex. There's no need for a Condition, and then checking for the existence of the bean, and then closing the ApplicationContext. Simply checking for the presence of the directory during WatchService creation, and throwing an exception will abort the application startup due to failure to create the bean.