sonar fix: Update App.java (#1898)

strategy/src/main/java/com/iluwatar/strategy/App.java

@@ -41,6 +41,10 @@ import lombok.extern.slf4j.Slf4j;
 @Slf4j
 public class App {
 
+  private static final String RED_DRAGON_EMERGES = "Red dragon emerges.";
+  private static final String GREEN_DRAGON_SPOTTED = "Green dragon spotted ahead!";
+  private static final String BLACK_DRAGON_LANDS = "Black dragon lands before you.";
+
   /**
    * Program entry point.
    *
@@ -48,38 +52,38 @@ public class App {
    */
   public static void main(String[] args) {
     // GoF Strategy pattern
-    LOGGER.info("Green dragon spotted ahead!");
+    LOGGER.info(GREEN_DRAGON_SPOTTED);
     var dragonSlayer = new DragonSlayer(new MeleeStrategy());
     dragonSlayer.goToBattle();
-    LOGGER.info("Red dragon emerges.");
+    LOGGER.info(RED_DRAGON_EMERGES);
     dragonSlayer.changeStrategy(new ProjectileStrategy());
     dragonSlayer.goToBattle();
-    LOGGER.info("Black dragon lands before you.");
+    LOGGER.info(BLACK_DRAGON_LANDS);
     dragonSlayer.changeStrategy(new SpellStrategy());
     dragonSlayer.goToBattle();
 
     // Java 8 functional implementation Strategy pattern
-    LOGGER.info("Green dragon spotted ahead!");
+    LOGGER.info(GREEN_DRAGON_SPOTTED);
     dragonSlayer = new DragonSlayer(
         () -> LOGGER.info("With your Excalibur you severe the dragon's head!"));
     dragonSlayer.goToBattle();
-    LOGGER.info("Red dragon emerges.");
+    LOGGER.info(RED_DRAGON_EMERGES);
     dragonSlayer.changeStrategy(() -> LOGGER.info(
         "You shoot the dragon with the magical crossbow and it falls dead on the ground!"));
     dragonSlayer.goToBattle();
-    LOGGER.info("Black dragon lands before you.");
+    LOGGER.info(BLACK_DRAGON_LANDS);
     dragonSlayer.changeStrategy(() -> LOGGER.info(
         "You cast the spell of disintegration and the dragon vaporizes in a pile of dust!"));
     dragonSlayer.goToBattle();
 
     // Java 8 lambda implementation with enum Strategy pattern
-    LOGGER.info("Green dragon spotted ahead!");
+    LOGGER.info(GREEN_DRAGON_SPOTTED);
     dragonSlayer.changeStrategy(LambdaStrategy.Strategy.MeleeStrategy);
     dragonSlayer.goToBattle();
-    LOGGER.info("Red dragon emerges.");
+    LOGGER.info(RED_DRAGON_EMERGES);
     dragonSlayer.changeStrategy(LambdaStrategy.Strategy.ProjectileStrategy);
     dragonSlayer.goToBattle();
-    LOGGER.info("Black dragon lands before you.");
+    LOGGER.info(BLACK_DRAGON_LANDS);
     dragonSlayer.changeStrategy(LambdaStrategy.Strategy.SpellStrategy);
     dragonSlayer.goToBattle();
   }