📍Use lombok, reformat, and optimize the code (#1560)

* Use lombok, reformat, and optimize the code

* Fix merge conflicts and some sonar issues

Co-authored-by: va1m <va1m@email.com>

zh/observer/README.md

@@ -42,20 +42,18 @@ public interface WeatherObserver {
   void update(WeatherType currentWeather);
 }
 
+@Slf4j
 public class Orcs implements WeatherObserver {
 
-  private static final Logger LOGGER = LoggerFactory.getLogger(Orcs.class);
-
   @Override
   public void update(WeatherType currentWeather) {
     LOGGER.info("The orcs are facing " + currentWeather.getDescription() + " weather now");
   }
 }
 
+@Slf4j
 public class Hobbits implements WeatherObserver {
 
-  private static final Logger LOGGER = LoggerFactory.getLogger(Hobbits.class);
-
   @Override
   public void update(WeatherType currentWeather) {
     switch (currentWeather) {
@@ -67,10 +65,9 @@ public class Hobbits implements WeatherObserver {
 然后这里是不断变化的天气。
 
 ```java
+@Slf4j
 public class Weather {
 
-  private static final Logger LOGGER = LoggerFactory.getLogger(Weather.class);
-
   private WeatherType currentWeather;
   private final List<WeatherObserver> observers;