diff --git a/.github/workflows/gradle.yml b/.github/workflows/gradle.yml
index fabe54421..110d83e33 100644
--- a/.github/workflows/gradle.yml
+++ b/.github/workflows/gradle.yml
@@ -16,13 +16,13 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v5
     - name: Set up JDK 11
-      uses: actions/setup-java@v2
+      uses: actions/setup-java@v5
       with:
         distribution: zulu
         java-version: '11'
-    - uses: actions/cache@v2
+    - uses: actions/cache@v4
       with:
         path: |
           ~/.gradle/caches
diff --git a/build.gradle b/build.gradle
index da384dc69..81a2eaa7d 100644
--- a/build.gradle
+++ b/build.gradle
@@ -16,7 +16,7 @@ spotless {
             include '**/*.java'
             exclude 'build/generated/**/*.*', 'build/generated-examples/**/*.*'
         }
-        googleJavaFormat()
+        googleJavaFormat('1.7')
     }
 }
 
diff --git a/src/main/java/io/spring/Util.java b/src/main/java/io/spring/Util.java
index d2512acca..b8c733d7c 100644
--- a/src/main/java/io/spring/Util.java
+++ b/src/main/java/io/spring/Util.java
@@ -4,4 +4,8 @@ public class Util {
   public static boolean isEmpty(String value) {
     return value == null || value.isEmpty();
   }
+
+  public static boolean isValidEmail(String email) {
+    return email != null && email.contains("@");
+  }
 }
diff --git a/src/test/java/io/spring/infrastructure/service/DefaultJwtServiceTest.java b/src/test/java/io/spring/infrastructure/service/DefaultJwtServiceTest.java
index 12929118a..b2261705e 100644
--- a/src/test/java/io/spring/infrastructure/service/DefaultJwtServiceTest.java
+++ b/src/test/java/io/spring/infrastructure/service/DefaultJwtServiceTest.java
@@ -13,7 +13,8 @@ public class DefaultJwtServiceTest {
 
   @BeforeEach
   public void setUp() {
-    jwtService = new DefaultJwtService("123123123123123123123123123123123123123123123123123123123123", 3600);
+    jwtService =
+        new DefaultJwtService("123123123123123123123123123123123123123123123123123123123123", 3600);
   }
 
   @Test