diff --git a/src/main/java/de/marhali/easyi18n/service/DataStore.java b/src/main/java/de/marhali/easyi18n/service/DataStore.java
index e537b43..634ebca 100644
--- a/src/main/java/de/marhali/easyi18n/service/DataStore.java
+++ b/src/main/java/de/marhali/easyi18n/service/DataStore.java
@@ -33,11 +33,11 @@ public class DataStore {
     private Translations translations;
     private String searchQuery;
 
-    public static DataStore getInstance(Project project) {
+    public static DataStore getInstance(@NotNull Project project) {
         return INSTANCE == null ? INSTANCE = new DataStore(project) : INSTANCE;
     }
 
-    private DataStore(Project project) {
+    private DataStore(@NotNull Project project) {
         this.project = project;
         this.synchronizer = new ArrayList<>();
     }