docs: improve docs and add explanation for flux (#2928)

flux/src/main/java/com/iluwatar/flux/action/ContentAction.java

@@ -24,19 +24,18 @@
  */
 package com.iluwatar.flux.action;
 
+import lombok.Getter;
+
 /**
  * ContentAction is a concrete action.
  */
 public class ContentAction extends Action {
 
+  @Getter
   private final Content content;
 
   public ContentAction(Content content) {
     super(ActionType.CONTENT_CHANGED);
     this.content = content;
   }
-
-  public Content getContent() {
-    return content;
-  }
 }

flux/src/main/java/com/iluwatar/flux/action/MenuAction.java

@@ -25,19 +25,18 @@
 package com.iluwatar.flux.action;
 
 
+import lombok.Getter;
+
 /**
  * MenuAction is a concrete action.
  */
 public class MenuAction extends Action {
 
+  @Getter
   private final MenuItem menuItem;
 
   public MenuAction(MenuItem menuItem) {
     super(ActionType.MENU_ITEM_SELECTED);
     this.menuItem = menuItem;
   }
-
-  public MenuItem getMenuItem() {
-    return menuItem;
-  }
 }

flux/src/main/java/com/iluwatar/flux/app/App.java

@@ -35,7 +35,7 @@ import com.iluwatar.flux.view.MenuView;
  * Flux is the application architecture that Facebook uses for building client-side web
  * applications. Flux eschews MVC in favor of a unidirectional data flow. When a user interacts with
  * a React view, the view propagates an action through a central dispatcher, to the various stores
- * that hold the application's data and business logic, which updates all of the views that are
+ * that hold the application's data and business logic, which updates all the views that are
  * affected.
  *
  * <p>This example has two views: menu and content. They represent typical main menu and content

flux/src/main/java/com/iluwatar/flux/dispatcher/Dispatcher.java

@@ -32,12 +32,14 @@ import com.iluwatar.flux.action.MenuItem;
 import com.iluwatar.flux.store.Store;
 import java.util.LinkedList;
 import java.util.List;
+import lombok.Getter;
 
 /**
  * Dispatcher sends Actions to registered Stores.
  */
 public final class Dispatcher {
 
+  @Getter
   private static Dispatcher instance = new Dispatcher();
 
   private final List<Store> stores = new LinkedList<>();
@@ -45,10 +47,6 @@ public final class Dispatcher {
   private Dispatcher() {
   }
 
-  public static Dispatcher getInstance() {
-    return instance;
-  }
-
   public void registerStore(Store store) {
     stores.add(store);
   }

flux/src/main/java/com/iluwatar/flux/store/ContentStore.java

@@ -28,12 +28,14 @@ import com.iluwatar.flux.action.Action;
 import com.iluwatar.flux.action.ActionType;
 import com.iluwatar.flux.action.Content;
 import com.iluwatar.flux.action.ContentAction;
+import lombok.Getter;
 
 /**
  * ContentStore is a concrete store.
  */
 public class ContentStore extends Store {
 
+  @Getter
   private Content content = Content.PRODUCTS;
 
   @Override
@@ -44,8 +46,4 @@ public class ContentStore extends Store {
       notifyChange();
     }
   }
-
-  public Content getContent() {
-    return content;
-  }
 }

flux/src/main/java/com/iluwatar/flux/store/MenuStore.java

@@ -28,12 +28,14 @@ import com.iluwatar.flux.action.Action;
 import com.iluwatar.flux.action.ActionType;
 import com.iluwatar.flux.action.MenuAction;
 import com.iluwatar.flux.action.MenuItem;
+import lombok.Getter;
 
 /**
  * MenuStore is a concrete store.
  */
 public class MenuStore extends Store {
 
+  @Getter
   private MenuItem selected = MenuItem.HOME;
 
   @Override
@@ -44,8 +46,4 @@ public class MenuStore extends Store {
       notifyChange();
     }
   }
-
-  public MenuItem getSelected() {
-    return selected;
-  }
 }