diff --git a/gmail/snippets/src/main/java/EnableAutoReply.java b/gmail/snippets/src/main/java/EnableAutoReply.java
index ef6e052c..33ffd77b 100644
--- a/gmail/snippets/src/main/java/EnableAutoReply.java
+++ b/gmail/snippets/src/main/java/EnableAutoReply.java
@@ -1,4 +1,4 @@
-// Copyright 2021 Google LLC
+// Copyright 2022 Google LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -34,13 +34,19 @@ public class EnableAutoReply {
     /**
      * Enables the auto reply
      *
-     * @throws IOException
+     * @return the reply message and response metadata.
+     * @throws IOException - if service account credentials file not found.
      */
-    public static void autoReply() throws IOException{
-        // Load pre-authorized user credentials from the environment.
-        // TODO(developer) - See https://developers.google.com/identity for
-        // guides on implementing OAuth2 for your application.
-        GoogleCredentials credentials = GoogleCredentials.getApplicationDefault().createScoped(Collections.singleton(GmailScopes.GMAIL_SETTINGS_BASIC));
+    public static VacationSettings autoReply() throws IOException{
+        // TODO(developer) - Replace with your email address.
+        String USER_EMAIL_ADDRESS = "gduser1@workspacesamples.dev";
+
+        /* Load pre-authorized user credentials from the environment.
+           TODO(developer) - See https://developers.google.com/identity for
+            guides on implementing OAuth2 for your application. */
+        GoogleCredentials credentials = GoogleCredentials.getApplicationDefault()
+                .createScoped(Collections.singleton(GmailScopes.GMAIL_SETTINGS_BASIC))
+                .createDelegated(USER_EMAIL_ADDRESS);
         HttpRequestInitializer requestInitializer = new HttpCredentialsAdapter(
                 credentials);
 
@@ -57,12 +63,16 @@ public static void autoReply() throws IOException{
                     .setEnableAutoReply(true)
                     .setResponseBodyHtml("I am on vacation and will reply when I am back in the office. Thanks!")
                     .setRestrictToDomain(true)
-                    .setStartTime(LocalDateTime.now().toEpochSecond(ZoneOffset.from(ZonedDateTime.now())) * 1000)
-                    .setEndTime(LocalDateTime.now().plusDays(7).toEpochSecond(ZoneOffset.from(ZonedDateTime.now())) * 1000);
+                    .setStartTime(LocalDateTime.now()
+                            .toEpochSecond(ZoneOffset.from(ZonedDateTime.now())) * 1000)
+                    .setEndTime(LocalDateTime.now().plusDays(7)
+                            .toEpochSecond(ZoneOffset.from(ZonedDateTime.now())) * 1000);
 
-            VacationSettings response = service.users().settings().updateVacation("me", vacationSettings).execute();
+            VacationSettings response = service.users().settings()
+                    .updateVacation("me", vacationSettings).execute();
             // Prints the auto-reply response body
             System.out.println("Enabled auto reply with message : "+response.getResponseBodyHtml());
+            return response;
         } catch (GoogleJsonResponseException e) {
             // TODO(developer) - handle error appropriately
             System.err.println("Unable to enable auto reply: " + e.getDetails());
diff --git a/gmail/snippets/src/test/java/TestEnableAutoReply.java b/gmail/snippets/src/test/java/TestEnableAutoReply.java
new file mode 100644
index 00000000..04778cfa
--- /dev/null
+++ b/gmail/snippets/src/test/java/TestEnableAutoReply.java
@@ -0,0 +1,28 @@
+// Copyright 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+
+import com.google.api.services.gmail.model.VacationSettings;
+import org.junit.Test;
+import java.io.IOException;
+import static org.junit.Assert.assertNotNull;
+
+public class TestEnableAutoReply extends EnableAutoReply {
+
+    @Test
+    public void testAutoReply() throws IOException {
+        VacationSettings settings = EnableAutoReply.autoReply();
+        assertNotNull(settings);
+    }
+}
\ No newline at end of file