diff --git a/app/src/main/java/com/example/sprout/refactor/adapter/DiffCallback.java b/app/src/main/java/com/example/sprout/refactor/adapter/DiffCallback.java
deleted file mode 100644
index aa637c3..0000000
--- a/app/src/main/java/com/example/sprout/refactor/adapter/DiffCallback.java
+++ /dev/null
@@ -1,38 +0,0 @@
-package com.example.sprout.refactor.adapter;
-
-import android.support.v7.util.DiffUtil;
-
-import java.util.List;
-
-/**
- * DiffUtilのCallbackの基底クラス
- *
- * @param <T> 差分を出すクラス
- * @author matsumoto_k
- */
-public abstract class DiffCallback<T> extends DiffUtil.Callback {
-    final protected List<T> oldList;
-    final protected List<T> newList;
-
-    public DiffCallback(List<T> oldList, List<T> newList) {
-        this.oldList = oldList;
-        this.newList = newList;
-    }
-
-    @Override
-    public int getOldListSize() {
-        return oldList.size();
-    }
-
-    @Override
-    public int getNewListSize() {
-        return newList.size();
-    }
-
-    @Override
-    public boolean areItemsTheSame(int oldItemPosition, int newItemPosition) {
-        return oldList.get(oldItemPosition) == newList.get(newItemPosition);
-    }
-
-    public abstract Object getChangePayload(int oldItemPosition, int newItemPosition);
-}
diff --git a/app/src/main/java/com/example/sprout/refactor/adapter/MemberDiffCallBack.java b/app/src/main/java/com/example/sprout/refactor/adapter/MemberDiffCallBack.java
deleted file mode 100644
index 77b1c9d..0000000
--- a/app/src/main/java/com/example/sprout/refactor/adapter/MemberDiffCallBack.java
+++ /dev/null
@@ -1,26 +0,0 @@
-package com.example.sprout.refactor.adapter;
-
-import com.example.sprout.refactor.model.entity.Member;
-
-import java.util.List;
-
-/**
- * userIdからMemberの差分を出す
- *
- * @author matsumoto_k
- */
-public class MemberDiffCallBack extends DiffCallback<Member> {
-    public MemberDiffCallBack(List<Member> oldList, List<Member> newList) {
-        super(oldList, newList);
-    }
-
-    @Override
-    public boolean areContentsTheSame(int oldItemPosition, int newItemPosition) {
-        return oldList.get(oldItemPosition).getUserId() == newList.get(newItemPosition).getUserId();
-    }
-
-    @Override
-    public Object getChangePayload(int oldItemPosition, int newItemPosition) {
-        return null;
-    }
-}
diff --git a/app/src/main/java/com/example/sprout/refactor/adapter/RoomDiffCallBack.java b/app/src/main/java/com/example/sprout/refactor/adapter/RoomDiffCallBack.java
deleted file mode 100644
index 47c8450..0000000
--- a/app/src/main/java/com/example/sprout/refactor/adapter/RoomDiffCallBack.java
+++ /dev/null
@@ -1,27 +0,0 @@
-package com.example.sprout.refactor.adapter;
-
-import com.example.sprout.refactor.model.entity.Room;
-
-import java.util.List;
-
-/**
- * roomIdからRoomの差分を出す
- *
- * @author matsumoto_k
- */
-public class RoomDiffCallBack extends DiffCallback<Room> {
-
-    public RoomDiffCallBack(List<Room> oldList, List<Room> newList) {
-        super(oldList, newList);
-    }
-
-    @Override
-    public boolean areContentsTheSame(int oldItemPosition, int newItemPosition) {
-        return oldList.get(oldItemPosition).getRoomId() == newList.get(newItemPosition).getRoomId();
-    }
-
-    @Override
-    public Object getChangePayload(int oldItemPosition, int newItemPosition) {
-        return null;
-    }
-}
diff --git a/app/src/main/java/com/example/sprout/refactor/adapter/RoomListAdapter.java b/app/src/main/java/com/example/sprout/refactor/adapter/RoomListAdapter.java
index 9318aa0..058ca6d 100644
--- a/app/src/main/java/com/example/sprout/refactor/adapter/RoomListAdapter.java
+++ b/app/src/main/java/com/example/sprout/refactor/adapter/RoomListAdapter.java
@@ -50,10 +50,9 @@
     }
 
     public void setDataAndRefresh(ArrayList<Room> items) {
-        List<Room> oldItems = this.items;
-        DiffUtil.DiffResult diffResult = DiffUtil.calculateDiff(new RoomDiffCallBack(oldItems, items));
+        this.items.clear();
         this.items = items;
-        diffResult.dispatchUpdatesTo(this);
+        notifyDataSetChanged();
     }
 
     @Override
diff --git a/app/src/main/java/com/example/sprout/refactor/registration.puml b/app/src/main/java/com/example/sprout/refactor/registration.puml
deleted file mode 100644
index 306393a..0000000
--- a/app/src/main/java/com/example/sprout/refactor/registration.puml
+++ /dev/null
@@ -1,60 +0,0 @@
-@startuml
-
-class ModelLocator{
-    registrationRepository : RegistrationRepository
-}
-class AppCompatActivity
-interface ViewContract{
-    void startActivity()
-    void finishActivity()
-    void showShortToast(String message)
-    void showLongToast(String message)
-}
-interface LifecycleObserver
-class Repository
-class RegistrationRepository{
-    void registration(String userName)
-    accountObservable : Observable<Account>
-}
-class RegistrationService{
-    @POST Call<Account> registration(String userName)
-}
-class RegistrationActivity
-class RegistrationViewModel{
-    userName : ObservableField<String>
-    registrationRepository : RegistrationRepository
-    viewContract : ViewContract
-    observer: Observer<Account>
-    void onClickRegistration(String userName)
-    void onResume()
-    void onPause()
-}
-
-abstract class Observable<T>{
-    observers : ArrayList<Observer<T>>
-    void addObserver(Observer<T> observer)
-    void removeObserver(Observer<T> observer)
-    void notifyObservers(T t)
-    void notifyError(Throwable t)
-}
-
-abstract class Observer<T>{
-    void notify(T t)
-    void error(Throwable t)
-}
-
-ModelLocator o-- RegistrationRepository
-Repository <|-- RegistrationRepository
-Repository o-- OkHttpClient
-RegistrationViewModel o-- RegistrationRepository
-RegistrationRepository o-- RegistrationService
-
-AppCompatActivity <|-down- RegistrationActivity
-ViewContract <|.down. RegistrationActivity
-RegistrationActivity o-down- RegistrationViewModel
-LifecycleObserver <|.down. RegistrationViewModel
-RegistrationViewModel o-up- ViewContract
-
-RegistrationViewModel o-- Observer
-RegistrationRepository o-- Observable
-@enduml
\ No newline at end of file