[java][chat_rollout][03_method_call] Add ChatRolloutPercentageRepository

Author: rgomezcasas

examples/java/java-chat_rollout-03_method_call/src/main/java/tv/codely/chat_rollout/ChatController.java

@@ -3,14 +3,14 @@
 import java.util.Random;
 
 public final class ChatController {
-    private final int newChatRolloutPercentage;
+    private final ChatRolloutPercentageRepository rolloutRepository;
 
-    public ChatController(int newChatRolloutPercentage) {
-        this.newChatRolloutPercentage = newChatRolloutPercentage;
+    public ChatController(ChatRolloutPercentageRepository rolloutRepository) {
+        this.rolloutRepository = rolloutRepository;
     }
 
     public String pullMessages() {
-        if (new Random().nextInt(100) <= newChatRolloutPercentage) {
+        if (new Random().nextInt(100) <= rolloutRepository.percentage()) {
             return "Messages from the NEW chat system";
         } else {
             return "Messages from the OLD chat system";

examples/java/java-chat_rollout-03_method_call/src/main/java/tv/codely/chat_rollout/ChatRolloutPercentageRepository.java

@@ -0,0 +1,5 @@
+package tv.codely.chat_rollout;
+
+public interface ChatRolloutPercentageRepository {
+    int percentage();
+}

examples/java/java-chat_rollout-03_method_call/src/main/java/tv/codely/chat_rollout/InMemoryChatRolloutPercentageRepository.java

@@ -0,0 +1,8 @@
+package tv.codely.chat_rollout;
+
+public final class InMemoryChatRolloutPercentageRepository implements ChatRolloutPercentageRepository {
+    @Override
+    public int percentage() {
+        return 30;
+    }
+}

examples/java/java-chat_rollout-03_method_call/src/test/java/tv/codely/chat_rollout/AlwaysNewChatChatRolloutPercentageRepository.java

@@ -0,0 +1,8 @@
+package tv.codely.chat_rollout;
+
+public final class AlwaysNewChatChatRolloutPercentageRepository implements ChatRolloutPercentageRepository {
+    @Override
+    public int percentage() {
+        return 100;
+    }
+}

examples/java/java-chat_rollout-03_method_call/src/test/java/tv/codely/chat_rollout/AlwaysOldChatChatRolloutPercentageRepository.java

@@ -0,0 +1,9 @@
+package tv.codely.chat_rollout;
+
+public final class AlwaysOldChatChatRolloutPercentageRepository implements ChatRolloutPercentageRepository {
+    @Override
+    public int percentage() {
+        return 0;
+    }
+}
+

examples/java/java-chat_rollout-03_method_call/src/test/java/tv/codely/chat_rollout/ChatControllerShould.java

@@ -7,14 +7,14 @@
 public final class ChatControllerShould {
     @Test
     void should_use_the_old_chat_system_pulling_messages() {
-        var controller = new ChatController(0);
+        var controller = new ChatController(new AlwaysOldChatChatRolloutPercentageRepository());
 
         assertEquals("Messages from the OLD chat system", controller.pullMessages());
     }
 
     @Test
     void should_use_the_new_chat_system_pulling_messages() {
-        var controller = new ChatController(100);
+        var controller = new ChatController(new AlwaysNewChatChatRolloutPercentageRepository());
 
         assertEquals("Messages from the NEW chat system", controller.pullMessages());
     }