public class HelloSpeaker {    private Logger logger =            Logger.getLogger(this.getClass().getName());    public void hello(String name) {        // 方法執行開始時留下日誌        logger.log(Level.INFO, "hello method starts....");        // 程式主要功能        System.out.println("Hello, " + name);        // 方法執行完畢前留下日誌        logger.log(Level.INFO, "hello method ends....");    }}