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
new file mode 100644
index 0000000..3fc1923
--- /dev/null
+++ b/app/src/main/java/com/example/sprout/refactor/notification/Observable.java
@@ -0,0 +1,35 @@
+package com.example.sprout.refactor.notification;
+
+import java.util.ArrayList;
+
+/**
+ * Observable
+ *
+ * @param <T> 監視したい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);
+    }
+}