diff --git a/neoemf-data/hbase/src/main/java/fr/inria/atlanmod/neoemf/data/hbase/store/DirectWriteHBaseStore.java b/neoemf-data/hbase/src/main/java/fr/inria/atlanmod/neoemf/data/hbase/store/DirectWriteHBaseStore.java
index 6674476374..9eaac4794e 100644
--- a/neoemf-data/hbase/src/main/java/fr/inria/atlanmod/neoemf/data/hbase/store/DirectWriteHBaseStore.java
+++ b/neoemf-data/hbase/src/main/java/fr/inria/atlanmod/neoemf/data/hbase/store/DirectWriteHBaseStore.java
@@ -263,7 +263,7 @@ public EStructuralFeature getContainingFeature(InternalEObject internalObject) {
     @Override
     public EObject eObject(Id id) {
         PersistentEObject object = null;
-        if(id != null) {
+        if(nonNull(id)) {
             EClass eClass = resolveInstanceOf(id);
             object = persistentObjectsCache.get(id, new PersistentEObjectCacheLoader(eClass));
             if (object.resource() != resource()) {
diff --git a/neoemf-data/map/berkeleydb/src/main/java/fr/inria/atlanmod/neoemf/data/berkeleydb/store/DirectWriteBerkeleyDbStore.java b/neoemf-data/map/berkeleydb/src/main/java/fr/inria/atlanmod/neoemf/data/berkeleydb/store/DirectWriteBerkeleyDbStore.java
index 77146a4312..36df64cef1 100644
--- a/neoemf-data/map/berkeleydb/src/main/java/fr/inria/atlanmod/neoemf/data/berkeleydb/store/DirectWriteBerkeleyDbStore.java
+++ b/neoemf-data/map/berkeleydb/src/main/java/fr/inria/atlanmod/neoemf/data/berkeleydb/store/DirectWriteBerkeleyDbStore.java
@@ -299,7 +299,7 @@ public EStructuralFeature getContainingFeature(InternalEObject internalObject) {
     @Override
     public EObject eObject(Id id) {
         PersistentEObject object = null;
-        if(id != null) {
+        if(nonNull(id)) {
             EClass eClass = resolveInstanceOf(id);
             object = persistentObjectsCache.get(id, new PersistentEObjectCacheLoader(eClass));
             if (object.resource() != resource()) {
diff --git a/neoemf-data/map/mapdb/src/main/java/fr/inria/atlanmod/neoemf/data/mapdb/store/DirectWriteMapDbStore.java b/neoemf-data/map/mapdb/src/main/java/fr/inria/atlanmod/neoemf/data/mapdb/store/DirectWriteMapDbStore.java
index cf24fc665a..743d6aa845 100644
--- a/neoemf-data/map/mapdb/src/main/java/fr/inria/atlanmod/neoemf/data/mapdb/store/DirectWriteMapDbStore.java
+++ b/neoemf-data/map/mapdb/src/main/java/fr/inria/atlanmod/neoemf/data/mapdb/store/DirectWriteMapDbStore.java
@@ -312,7 +312,7 @@ public EStructuralFeature getContainingFeature(InternalEObject internalObject) {
     @Override
     public EObject eObject(Id id) {
         PersistentEObject object = null;
-        if(id != null) {
+        if(nonNull(id)) {
             EClass eClass = resolveInstanceOf(id);
             object = persistentObjectsCache.get(id, new PersistentEObjectCacheLoader(eClass));
             if (object.resource() != resource()) {