diff --git a/app/src/main/java/com/example/sprout/refactor/contract/ViewContract.java b/app/src/main/java/com/example/sprout/refactor/contract/ViewContract.java
deleted file mode 100644
index 5913869..0000000
--- a/app/src/main/java/com/example/sprout/refactor/contract/ViewContract.java
+++ /dev/null
@@ -1,18 +0,0 @@
-package com.example.sprout.refactor.contract;
-
-import com.example.sprout.refactor.common.ActivityEvent;
-
-/**
- * トーストのContract
- *
- * @author matsumoto_k
- */
-public interface ViewContract {
-    public void startActivity(ActivityEvent event);
-
-    public void finishActivity();
-
-    public void showShortToast(String message);
-
-    public void showLongToast(String message);
-}
diff --git a/app/src/main/java/com/example/sprout/refactor/notification/Observable.java b/app/src/main/java/com/example/sprout/refactor/notification/Observable.java
deleted file mode 100644
index f7cdbac..0000000
--- a/app/src/main/java/com/example/sprout/refactor/notification/Observable.java
+++ /dev/null
@@ -1,35 +0,0 @@
-package com.example.sprout.refactor.notification;
-
-import java.util.ArrayList;
-
-/**
- * Observable
- *
- * @param <T> 監視するObject
- * @author matsumoto_k
- */
-
-public class Observable<T> {
-
-    private ArrayList<Observer<T>> observers = new ArrayList<>();
-
-    public void notifyObservers(T t) {
-        for (Observer<T> observer : observers) {
-            observer.notify(t);
-        }
-    }
-
-    public void notifyError(Throwable throwable) {
-        for (Observer<T> observer : observers) {
-            observer.error(throwable);
-        }
-    }
-
-    public void addObserver(Observer<T> observer) {
-        observers.add(observer);
-    }
-
-    public void removeObserver(Observer<T> observer) {
-        observers.remove(observer);
-    }
-}
diff --git a/app/src/main/java/com/example/sprout/refactor/notification/Observer.java b/app/src/main/java/com/example/sprout/refactor/notification/Observer.java
deleted file mode 100644
index a2ee92d..0000000
--- a/app/src/main/java/com/example/sprout/refactor/notification/Observer.java
+++ /dev/null
@@ -1,13 +0,0 @@
-package com.example.sprout.refactor.notification;
-
-/**
- * Observer
- *
- * @param <T> 監視させるObject
- * @author matsumoto_k
- */
-public abstract class Observer<T> {
-    public abstract void notify(T t);
-
-    public abstract void error(Throwable throwable);
-}
diff --git a/app/src/main/java/com/example/sprout/refactor/repository/RoomRepository.java b/app/src/main/java/com/example/sprout/refactor/repository/RoomRepository.java
index aafd064..057b15b 100644
--- a/app/src/main/java/com/example/sprout/refactor/repository/RoomRepository.java
+++ b/app/src/main/java/com/example/sprout/refactor/repository/RoomRepository.java
@@ -19,10 +19,6 @@
 public class RoomRepository extends Repository {
 
     private RoomService roomService = null;
-    private com.example.sprout.refactor.notification.Observable<Room> roomObservable = new com.example.sprout.refactor.notification.Observable<>();
-    private com.example.sprout.refactor.notification.Observable<Rooms> roomsObservable = new com.example.sprout.refactor.notification.Observable<>();
-    private com.example.sprout.refactor.notification.Observable<RoomResponse> roomResponseObservable = new com.example.sprout.refactor.notification.Observable<>();
-    private com.example.sprout.refactor.notification.Observable<Void> voidObservable = new com.example.sprout.refactor.notification.Observable<>();
 
     public RoomRepository() {
         this.roomService = new Retrofit
@@ -62,20 +58,4 @@
     public Observable<RoomResponse> enterRoomWithKey(int roomId, int userId, String key) {
         return roomService.enterRoomWithKey(roomId, userId, key);
     }
-
-    public com.example.sprout.refactor.notification.Observable<Room> getRoomObservable() {
-        return roomObservable;
-    }
-
-    public com.example.sprout.refactor.notification.Observable<Rooms> getRoomsObservable() {
-        return roomsObservable;
-    }
-
-    public com.example.sprout.refactor.notification.Observable<RoomResponse> getRoomResponseObservable() {
-        return roomResponseObservable;
-    }
-
-    public com.example.sprout.refactor.notification.Observable<Void> getVoidObservable() {
-        return voidObservable;
-    }
 }