diff --git a/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java b/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java
index 37e4b67..bd93bbe 100644
--- a/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java
+++ b/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java
@@ -18,5 +18,6 @@
         findViewById(R.id.observable_btn).setOnClickListener(view -> rxProcess.observable());
         findViewById(R.id.just_btn).setOnClickListener(view -> rxProcess.just());
         findViewById(R.id.fromarray_btn).setOnClickListener(view -> rxProcess.fromArray());
+        findViewById(R.id.range_btn).setOnClickListener(view -> rxProcess.range());
     }
 }
diff --git a/app/src/main/java/org/ntlab/developrx/JavaRxProcess.java b/app/src/main/java/org/ntlab/developrx/JavaRxProcess.java
index a2e5dd2..836ff8a 100644
--- a/app/src/main/java/org/ntlab/developrx/JavaRxProcess.java
+++ b/app/src/main/java/org/ntlab/developrx/JavaRxProcess.java
@@ -136,4 +136,9 @@
         Flowable<String> flowable = Flowable.fromArray("A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K");
         flowable.subscribe(new DebugSubscriber<>());
     }
+
+    public void range() {
+        Flowable<Integer> flowable = Flowable.range(10, 3);
+        flowable.subscribe(new DebugSubscriber<>());
+    }
 }
diff --git a/app/src/main/res/layout/activity_main_java.xml b/app/src/main/res/layout/activity_main_java.xml
index 97c0faf..e131c63 100644
--- a/app/src/main/res/layout/activity_main_java.xml
+++ b/app/src/main/res/layout/activity_main_java.xml
@@ -41,6 +41,14 @@
             android:text="fromarray"
             app:layout_constraintStart_toStartOf="parent"
             app:layout_constraintTop_toBottomOf="@id/just_btn" />
+
+        <Button
+            android:id="@+id/range_btn"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="range"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@id/fromarray_btn" />
     </android.support.constraint.ConstraintLayout>
 
 </ScrollView>