Use case build house hotel

src/main/java/tutorial/BuildProcessor.java

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+package tutorial;
+
+public class BuildProcessor {
+    private Player player;
+    private Properties properties;
+
+    public BuildProcessor(Player player, Properties properties) {
+        // controller pass an object of Player and an object of Properties
+        this.player = player;
+        this.properties = properties;
+    }
+
+    public boolean Build(House house) {
+        // controller calls HouseHotelGenerator to generate a house
+        if (this.BuildChecker(house)){
+            this.player.loseMoney(house.getPrice());
+            this.properties.buildBuilding(house);
+            return true;
+        }
+        return false;
+    }
+
+    public boolean Build(Hotel hotel) {
+        // controller calls HouseHotelGenerator to generate a house
+        if (this.BuildChecker(hotel)){
+            this.player.loseMoney(hotel.getPrice());
+            // since when hotel is built, all houses are removed.
+            this.properties.removeBuilding();
+            this.properties.buildBuilding(hotel);
+            return true;
+        }
+        return false;
+    }
+
+    public boolean BuildChecker(Building building) {
+        // helper function to avoid duplicated code
+        if (this.player.getMoney() >= building.getPrice()){
+            return this.properties.getOwner() == this.player;
+        }
+        return false;
+    }
+
+}

src/main/java/tutorial/HouseHotelGenerator.java

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+package tutorial;
+
+public class HouseHotelGenerator {
+    // this class is to solve hard dependency issue (this can be tested independently)
+    // when controller calls BuildProcessor, it should also call this generator as well
+
+    public House generateHouse(Integer price, Integer rent, Integer mortgageValue) {
+        return new House(price,rent,mortgageValue);
+    }
+
+    public Hotel generateHotel(Integer price, Integer rent, Integer mortgageValue) {
+        return new Hotel(price, rent, mortgageValue);
+    }
+}