Use enums instead os switch blocks

Its better to use enums instead of switch
blocks which makes the code longer and difficult
to maintain as and when new state appears.

observer/README.md

@@ -13,18 +13,18 @@ tags:
 Dependents, Publish-Subscribe
 
 ## Intent
-Define a one-to-many dependency between objects so that when one object changes state, all its dependents are notified 
+Define a one-to-many dependency between objects so that when one object changes state, all its dependents are notified
 and updated automatically.
 
 ## Explanation
 
 Real world example
 
-> In a land far away lives the races of hobbits and orcs. Both of them are mostly outdoors so they closely follow the changes in weather. One could say that they are constantly observing the weather.        
+> In a land far away lives the races of hobbits and orcs. Both of them are mostly outdoors so they closely follow the changes in weather. One could say that they are constantly observing the weather.
 
 In plain words
 
-> Register as an observer to receive state changes in the object.   
+> Register as an observer to receive state changes in the object.
 
 Wikipedia says
 
@@ -46,22 +46,7 @@ public class Orcs implements WeatherObserver {
 
   @Override
   public void update(WeatherType currentWeather) {
-    switch (currentWeather) {
+    LOGGER.info("The hobbits are facing " + currentWeather.getDescription() + " weather now");
-      case COLD:
-        LOGGER.info("The orcs are freezing cold.");
-        break;
-      case RAINY:
-        LOGGER.info("The orcs are dripping wet.");
-        break;
-      case SUNNY:
-        LOGGER.info("The sun hurts the orcs' eyes.");
-        break;
-      case WINDY:
-        LOGGER.info("The orc smell almost vanishes in the wind.");
-        break;
-      default:
-        break;
-    }
   }
 }
 
@@ -72,21 +57,7 @@ public class Hobbits implements WeatherObserver {
   @Override
   public void update(WeatherType currentWeather) {
     switch (currentWeather) {
-      case COLD:
+      LOGGER.info("The hobbits are facing " + currentWeather.getDescription() + " weather now");
-        LOGGER.info("The hobbits are shivering in the cold weather.");
-        break;
-      case RAINY:
-        LOGGER.info("The hobbits look for cover from the rain.");
-        break;
-      case SUNNY:
-        LOGGER.info("The happy hobbits bade in the warm sun.");
-        break;
-      case WINDY:
-        LOGGER.info("The hobbits hold their hats tightly in the windy weather.");
-        break;
-      default:
-        break;
-    }
   }
 }
 ```
@@ -141,20 +112,20 @@ Here's the full example in action.
 
     weather.timePasses();
     // The weather changed to rainy.
-    // The orcs are dripping wet.
+    // The orcs are facing rainy weather now
-    // The hobbits look for cover from the rain.
+    // The hobbits are facing rainy weather now
     weather.timePasses();
     // The weather changed to windy.
-    // The orc smell almost vanishes in the wind.
+    // The orcs are facing windy weather now
-    // The hobbits hold their hats tightly in the windy weather.
+    // The hobbits are facing windy weather now
     weather.timePasses();
     // The weather changed to cold.
-    // The orcs are freezing cold.
+    // The orcs are facing cold weather now
-    // The hobbits are shivering in the cold weather.
+    // The hobbits are facing cold weather now
     weather.timePasses();
     // The weather changed to sunny.
-    // The sun hurts the orcs' eyes.
+    // The orcs are facing sunny weather now
-    // The happy hobbits bade in the warm sun.
+    // The hobbits are facing sunny weather now
 ```
 
 ## Class diagram

observer/etc/observer.urm.puml

@@ -33,7 +33,9 @@ package com.iluwatar.observer {
     + RAINY {static}
     + SUNNY {static}
     + WINDY {static}
+    + description String
     + toString() : String
+    + getDescription() : String
     + valueOf(name : String) : WeatherType {static}
     + values() : WeatherType[] {static}
   }
@@ -71,10 +73,10 @@ package com.iluwatar.observer.generic {
 Weather -->  "-currentWeather" WeatherType
 GWeather -->  "-currentWeather" WeatherType
 Weather -->  "-observers" WeatherObserver
-Hobbits ..|> WeatherObserver 
+Hobbits ..|> WeatherObserver
-Orcs ..|> WeatherObserver 
+Orcs ..|> WeatherObserver
-GHobbits ..|> Race 
+GHobbits ..|> Race
-GOrcs ..|> Race 
+GOrcs ..|> Race
-GWeather --|> Observable 
+GWeather --|> Observable
-Race --|> Observer 
+Race --|> Observer
-@enduml
+@enduml

observer/src/main/java/com/iluwatar/observer/Hobbits.java

@@ -35,21 +35,6 @@ public class Hobbits implements WeatherObserver {
 
   @Override
   public void update(WeatherType currentWeather) {
-    switch (currentWeather) {
+    LOGGER.info("The hobbits are facing " + currentWeather.getDescription() + " weather now");
-      case COLD:
-        LOGGER.info("The hobbits are shivering in the cold weather.");
-        break;
-      case RAINY:
-        LOGGER.info("The hobbits look for cover from the rain.");
-        break;
-      case SUNNY:
-        LOGGER.info("The happy hobbits bade in the warm sun.");
-        break;
-      case WINDY:
-        LOGGER.info("The hobbits hold their hats tightly in the windy weather.");
-        break;
-      default:
-        break;
-    }
   }
 }

observer/src/main/java/com/iluwatar/observer/Orcs.java

@@ -35,21 +35,6 @@ public class Orcs implements WeatherObserver {
 
   @Override
   public void update(WeatherType currentWeather) {
-    switch (currentWeather) {
+    LOGGER.info("The orcs are facing " + currentWeather.getDescription() + " weather now");
-      case COLD:
-        LOGGER.info("The orcs are freezing cold.");
-        break;
-      case RAINY:
-        LOGGER.info("The orcs are dripping wet.");
-        break;
-      case SUNNY:
-        LOGGER.info("The sun hurts the orcs' eyes.");
-        break;
-      case WINDY:
-        LOGGER.info("The orc smell almost vanishes in the wind.");
-        break;
-      default:
-        break;
-    }
   }
 }

observer/src/main/java/com/iluwatar/observer/WeatherType.java

@@ -28,7 +28,20 @@ package com.iluwatar.observer;
  */
 public enum WeatherType {
 
-  SUNNY, RAINY, WINDY, COLD;
+  SUNNY("Sunny"),
+  RAINY("Rainy"),
+  WINDY("Windy"),
+  COLD("Cold");
+
+  private final String description;
+
+  WeatherType(String description) {
+    this.description = description;
+  }
+
+  public String getDescription() {
+    return this.description;
+  }
 
   @Override
   public String toString() {

observer/src/main/java/com/iluwatar/observer/generic/GHobbits.java

@@ -36,21 +36,6 @@ public class GHobbits implements Race {
 
   @Override
   public void update(GWeather weather, WeatherType weatherType) {
-    switch (weatherType) {
+    LOGGER.info("The hobbits are facing " + weatherType.getDescription() + " weather now");
-      case COLD:
-        LOGGER.info("The hobbits are shivering in the cold weather.");
-        break;
-      case RAINY:
-        LOGGER.info("The hobbits look for cover from the rain.");
-        break;
-      case SUNNY:
-        LOGGER.info("The happy hobbits bade in the warm sun.");
-        break;
-      case WINDY:
-        LOGGER.info("The hobbits hold their hats tightly in the windy weather.");
-        break;
-      default:
-        break;
-    }
   }
 }

observer/src/main/java/com/iluwatar/observer/generic/GOrcs.java

@@ -36,21 +36,6 @@ public class GOrcs implements Race {
 
   @Override
   public void update(GWeather weather, WeatherType weatherType) {
-    switch (weatherType) {
+    LOGGER.info("The orcs are facing " + weatherType.getDescription() + " weather now");
-      case COLD:
-        LOGGER.info("The orcs are freezing cold.");
-        break;
-      case RAINY:
-        LOGGER.info("The orcs are dripping wet.");
-        break;
-      case SUNNY:
-        LOGGER.info("The sun hurts the orcs' eyes.");
-        break;
-      case WINDY:
-        LOGGER.info("The orc smell almost vanishes in the wind.");
-        break;
-      default:
-        break;
-    }
   }
 }

observer/src/test/java/com/iluwatar/observer/HobbitsTest.java

@@ -36,10 +36,10 @@ public class HobbitsTest extends WeatherObserverTest<Hobbits> {
   @Override
   public Collection<Object[]> dataProvider() {
     return List.of(
-            new Object[]{WeatherType.SUNNY, "The happy hobbits bade in the warm sun."},
+            new Object[]{WeatherType.SUNNY, "The hobbits are facing Sunny weather now"},
-            new Object[]{WeatherType.RAINY, "The hobbits look for cover from the rain."},
+            new Object[]{WeatherType.RAINY, "The hobbits are facing Rainy weather now"},
-            new Object[]{WeatherType.WINDY, "The hobbits hold their hats tightly in the windy weather."},
+            new Object[]{WeatherType.WINDY, "The hobbits are facing Windy weather now"},
-            new Object[]{WeatherType.COLD, "The hobbits are shivering in the cold weather."});
+            new Object[]{WeatherType.COLD, "The hobbits are facing Cold weather now"});
   }
 
   /**

observer/src/test/java/com/iluwatar/observer/OrcsTest.java

@@ -36,10 +36,10 @@ public class OrcsTest extends WeatherObserverTest<Orcs> {
   @Override
   public Collection<Object[]> dataProvider() {
     return List.of(
-            new Object[]{WeatherType.SUNNY, "The sun hurts the orcs' eyes."},
+            new Object[]{WeatherType.SUNNY, "The orcs are facing Sunny weather now"},
-            new Object[]{WeatherType.RAINY, "The orcs are dripping wet."},
+            new Object[]{WeatherType.RAINY, "The orcs are facing Rainy weather now"},
-            new Object[]{WeatherType.WINDY, "The orc smell almost vanishes in the wind."},
+            new Object[]{WeatherType.WINDY, "The orcs are facing Windy weather now"},
-            new Object[]{WeatherType.COLD, "The orcs are freezing cold."});
+            new Object[]{WeatherType.COLD, "The orcs are facing Cold weather now"});
   }
 
   /**

observer/src/test/java/com/iluwatar/observer/generic/GHobbitsTest.java

@@ -38,10 +38,10 @@ public class GHobbitsTest extends ObserverTest<GHobbits> {
   @Override
   public Collection<Object[]> dataProvider() {
     return List.of(
-            new Object[]{WeatherType.SUNNY, "The happy hobbits bade in the warm sun."},
+            new Object[]{WeatherType.SUNNY, "The hobbits are facing Sunny weather now"},
-            new Object[]{WeatherType.RAINY, "The hobbits look for cover from the rain."},
+            new Object[]{WeatherType.RAINY, "The hobbits are facing Rainy weather now"},
-            new Object[]{WeatherType.WINDY, "The hobbits hold their hats tightly in the windy weather."},
+            new Object[]{WeatherType.WINDY, "The hobbits are facing Windy weather now"},
-            new Object[]{WeatherType.COLD, "The hobbits are shivering in the cold weather."}
+            new Object[]{WeatherType.COLD, "The hobbits are facing Cold weather now"}
     );
   }
 

observer/src/test/java/com/iluwatar/observer/generic/OrcsTest.java

@@ -38,10 +38,10 @@ public class OrcsTest extends ObserverTest<GOrcs> {
   @Override
   public Collection<Object[]> dataProvider() {
     return List.of(
-            new Object[]{WeatherType.SUNNY, "The sun hurts the orcs' eyes."},
+            new Object[]{WeatherType.SUNNY, "The orcs are facing Sunny weather now"},
-            new Object[]{WeatherType.RAINY, "The orcs are dripping wet."},
+            new Object[]{WeatherType.RAINY, "The orcs are facing Rainy weather now"},
-            new Object[]{WeatherType.WINDY, "The orc smell almost vanishes in the wind."},
+            new Object[]{WeatherType.WINDY, "The orcs are facing Windy weather now"},
-            new Object[]{WeatherType.COLD, "The orcs are freezing cold."}
+            new Object[]{WeatherType.COLD, "The orcs are facing Cold weather now"}
     );
   }