diff --git a/jkube-kit/config/resource/src/main/java/org/eclipse/jkube/kit/config/resource/MappingConfig.java b/jkube-kit/config/resource/src/main/java/org/eclipse/jkube/kit/config/resource/MappingConfig.java
index 26dcac87b4..1198cd1589 100644
--- a/jkube-kit/config/resource/src/main/java/org/eclipse/jkube/kit/config/resource/MappingConfig.java
+++ b/jkube-kit/config/resource/src/main/java/org/eclipse/jkube/kit/config/resource/MappingConfig.java
@@ -38,6 +38,6 @@ public String[] getFilenamesAsArray() {
     }
 
     public boolean isValid() {
-        return kind != null && filenameTypes != null && filenameTypes.length() > 0;
+        return kind != null && filenameTypes != null && !filenameTypes.isEmpty();
     }
 }
diff --git a/jkube-kit/config/resource/src/test/java/org/eclipse/jkube/kit/config/resource/MappingConfigTest.java b/jkube-kit/config/resource/src/test/java/org/eclipse/jkube/kit/config/resource/MappingConfigTest.java
index 640835e0fb..37d7b1a0d4 100644
--- a/jkube-kit/config/resource/src/test/java/org/eclipse/jkube/kit/config/resource/MappingConfigTest.java
+++ b/jkube-kit/config/resource/src/test/java/org/eclipse/jkube/kit/config/resource/MappingConfigTest.java
@@ -58,9 +58,9 @@ void getFilenamesAsArray_whenTypesPresent_thenReturnsArray() {
   void isValid_withMissingKind_shouldReturnFalse() {
     // Given
     MappingConfig config = MappingConfig.builder()
-      .apiVersion("custom-cron-tab.example.com/v1")
-      .filenameTypes("crontab,cr")
-      .build();
+        .apiVersion("custom-cron-tab.example.com/v1")
+        .filenameTypes("crontab,cr")
+        .build();
     // When
     boolean result = config.isValid();
     // Then
@@ -71,9 +71,23 @@ void isValid_withMissingKind_shouldReturnFalse() {
   void isValid_withMissingFileNameTypes_shouldReturnFalse() {
     // Given
     MappingConfig config = MappingConfig.builder()
-      .apiVersion("custom-cron-tab.example.com/v1")
-      .kind("Foo")
-      .build();
+        .apiVersion("custom-cron-tab.example.com/v1")
+        .kind("Foo")
+        .build();
+    // When
+    boolean result = config.isValid();
+    // Then
+    assertThat(result).isFalse();
+  }
+
+  @Test
+  void isValid_withEmptyFileNameTypes_shouldReturnFalse() {
+    // Given
+    MappingConfig config = MappingConfig.builder()
+        .apiVersion("custom-cron-tab.example.com/v1")
+        .kind("Foo")
+        .filenameTypes("")
+        .build();
     // When
     boolean result = config.isValid();
     // Then
@@ -110,7 +124,7 @@ void isValid_withKindAndApiVersionAndFileName_shouldReturnTrue() {
   @Test
   void equalsAndHashCodeShouldMatch() {
     // Given
-    MappingConfig  mc1 = MappingConfig.builder().kind("Foo").filenameTypes("foos").build();
+    MappingConfig mc1 = MappingConfig.builder().kind("Foo").filenameTypes("foos").build();
     MappingConfig mc2 = MappingConfig.builder().kind("Foo").filenameTypes("foos").build();
     // When + Then
     assertThat(mc1)