diff --git a/afs-storage-api/src/test/java/com/powsybl/afs/storage/AbstractAppStorageTest.java b/afs-storage-api/src/test/java/com/powsybl/afs/storage/AbstractAppStorageTest.java
index 73432924..48994c3a 100644
--- a/afs-storage-api/src/test/java/com/powsybl/afs/storage/AbstractAppStorageTest.java
+++ b/afs-storage-api/src/test/java/com/powsybl/afs/storage/AbstractAppStorageTest.java
@@ -650,7 +650,7 @@ protected void testUpdateNodeMetadata(NodeInfo rootFolderInfo, AppStorage storag
         assertEventStack(new NodeMetadataUpdated(node.getId(), metadata));
 
         metadata.setString("test", "test");
-        assertThat(node.getGenericMetadata().getStrings().keySet().size()).isZero();
+        assertThat(node.getGenericMetadata().getStrings().keySet()).isEmpty();
 
         storage.setMetadata(node.getId(), cloneMetadata(metadata));
         storage.flush();
diff --git a/afs-ws/afs-ws-server-utils/src/main/java/com/powsybl/afs/ws/server/utils/SimpleKeyGenerator.java b/afs-ws/afs-ws-server-utils/src/main/java/com/powsybl/afs/ws/server/utils/SimpleKeyGenerator.java
index e28bb412..236a3ed4 100644
--- a/afs-ws/afs-ws-server-utils/src/main/java/com/powsybl/afs/ws/server/utils/SimpleKeyGenerator.java
+++ b/afs-ws/afs-ws-server-utils/src/main/java/com/powsybl/afs/ws/server/utils/SimpleKeyGenerator.java
@@ -15,11 +15,8 @@
  */
 public class SimpleKeyGenerator implements KeyGenerator {
 
-    private static final String SIMPLE_KEY = "simplekey";
-
     @Override
     public Key generateKey() {
         return Jwts.SIG.HS512.key().build();
-//        return new SecretKeySpec(SIMPLE_KEY.getBytes(), 0, SIMPLE_KEY.getBytes().length, "HMAC-SHA-256");
     }
 }