diff --git a/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/BatteryField.java b/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/BatteryField.java
index fc4302327..5de8a455a 100644
--- a/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/BatteryField.java
+++ b/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/BatteryField.java
@@ -10,6 +10,7 @@
 import com.powsybl.iidm.network.Battery;
 import com.powsybl.iidm.network.extensions.ActivePowerControl;
 import com.powsybl.iidm.network.extensions.ActivePowerControlAdder;
+import jakarta.validation.constraints.NotNull;
 
 /**
  * @author Seddik Yengui <Seddik.yengui at rte-france.com>
@@ -34,7 +35,7 @@ public static String getReferenceValue(Battery battery, String batteryField) {
         };
     }
 
-    public static void setNewValue(Battery battery, String batteryField, String newValue) {
+    public static void setNewValue(Battery battery, String batteryField, @NotNull String newValue) {
         BatteryField field = BatteryField.valueOf(batteryField);
         switch (field) {
             case MINIMUM_ACTIVE_POWER -> battery.setMinP(Double.parseDouble(newValue));
diff --git a/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/GeneratorField.java b/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/GeneratorField.java
index 2cd1d37fb..606a7f145 100644
--- a/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/GeneratorField.java
+++ b/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/GeneratorField.java
@@ -9,6 +9,7 @@
 
 import com.powsybl.iidm.network.Generator;
 import com.powsybl.iidm.network.extensions.*;
+import jakarta.validation.constraints.NotNull;
 
 /**
  * @author Seddik Yengui <Seddik.yengui at rte-france.com>
@@ -55,7 +56,7 @@ public static String getReferenceValue(Generator generator, String generatorFiel
         };
     }
 
-    public static void setNewValue(Generator generator, String generatorField, String newValue) {
+    public static void setNewValue(Generator generator, String generatorField, @NotNull String newValue) {
         GeneratorStartup generatorStartup = generator.getExtension(GeneratorStartup.class);
         GeneratorShortCircuit generatorShortCircuit = generator.getExtension(GeneratorShortCircuit.class);
         GeneratorField field = GeneratorField.valueOf(generatorField);
diff --git a/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/LoadField.java b/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/LoadField.java
index 4582df7d1..5660ce009 100644
--- a/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/LoadField.java
+++ b/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/LoadField.java
@@ -9,6 +9,7 @@
 
 import com.powsybl.iidm.network.Load;
 import com.powsybl.iidm.network.LoadType;
+import jakarta.validation.constraints.NotNull;
 
 /**
  * @author Seddik Yengui <Seddik.yengui at rte-france.com>
@@ -27,10 +28,10 @@ public static String getReferenceValue(Load load, String loadField) {
         };
     }
 
-    public static void setNewValue(Load load, String loadField, String newValue) {
+    public static void setNewValue(Load load, String loadField, @NotNull String newValue) {
         LoadField field = LoadField.valueOf(loadField);
         switch (field) {
-            case LOAD_TYPE -> load.setLoadType(newValue != null ? LoadType.valueOf(newValue) : null);
+            case LOAD_TYPE -> load.setLoadType(LoadType.valueOf(newValue));
             case ACTIVE_POWER -> load.setP0(Double.parseDouble(newValue));
             case REACTIVE_POWER -> load.setQ0(Double.parseDouble(newValue));
         }
diff --git a/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/ShuntCompensatorField.java b/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/ShuntCompensatorField.java
index 82ecc1a94..cb7894461 100644
--- a/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/ShuntCompensatorField.java
+++ b/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/ShuntCompensatorField.java
@@ -11,6 +11,7 @@
 import com.powsybl.iidm.network.ShuntCompensatorLinearModel;
 import com.powsybl.iidm.network.ShuntCompensatorModelType;
 import com.powsybl.iidm.network.VoltageLevel;
+import jakarta.validation.constraints.NotNull;
 import org.gridsuite.modification.server.NetworkModificationException;
 
 /**
@@ -33,7 +34,7 @@ public static String getReferenceValue(ShuntCompensator shuntCompensator, String
         };
     }
 
-    public static void setNewValue(ShuntCompensator shuntCompensator, String shuntCompensatorField, String newValue) {
+    public static void setNewValue(ShuntCompensator shuntCompensator, String shuntCompensatorField, @NotNull String newValue) {
         if (shuntCompensator.getModelType() != ShuntCompensatorModelType.LINEAR) {
             throw new NetworkModificationException(NetworkModificationException.Type.BY_FORMULA_MODIFICATION_ERROR,
                     String.format("Shunt compensator with %s model is not supported", shuntCompensator.getModelType()));
diff --git a/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/TwoWindingsTransformerField.java b/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/TwoWindingsTransformerField.java
index b60bfa937..5d3af2fbe 100644
--- a/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/TwoWindingsTransformerField.java
+++ b/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/TwoWindingsTransformerField.java
@@ -10,6 +10,7 @@
 import com.powsybl.iidm.network.PhaseTapChanger;
 import com.powsybl.iidm.network.RatioTapChanger;
 import com.powsybl.iidm.network.TwoWindingsTransformer;
+import jakarta.validation.constraints.NotNull;
 
 /**
  * @author Seddik Yengui <Seddik.yengui at rte-france.com>
@@ -54,7 +55,7 @@ public static String getReferenceValue(TwoWindingsTransformer transformer, Strin
         };
     }
 
-    public static void setNewValue(TwoWindingsTransformer transformer, String twoWindingsTransformerField, String newValue) {
+    public static void setNewValue(TwoWindingsTransformer transformer, String twoWindingsTransformerField, @NotNull String newValue) {
         TwoWindingsTransformerField field = TwoWindingsTransformerField.valueOf(twoWindingsTransformerField);
         final PhaseTapChanger phaseTapChanger = transformer.getPhaseTapChanger();
         final RatioTapChanger ratioTapChanger = transformer.getRatioTapChanger();
diff --git a/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/VoltageLevelField.java b/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/VoltageLevelField.java
index 2303457c2..bbede673a 100644
--- a/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/VoltageLevelField.java
+++ b/src/main/java/org/gridsuite/modification/server/dto/byfilter/equipmentfield/VoltageLevelField.java
@@ -10,6 +10,7 @@
 import com.powsybl.iidm.network.VoltageLevel;
 import com.powsybl.iidm.network.extensions.IdentifiableShortCircuit;
 import com.powsybl.iidm.network.extensions.IdentifiableShortCircuitAdder;
+import jakarta.validation.constraints.NotNull;
 
 /**
  * @author Seddik Yengui <Seddik.yengui at rte-france.com>
@@ -33,7 +34,7 @@ public static String getReferenceValue(VoltageLevel voltageLevel, String voltage
         };
     }
 
-    public static void setNewValue(VoltageLevel voltageLevel, String voltageLevelField, String newValue) {
+    public static void setNewValue(VoltageLevel voltageLevel, String voltageLevelField, @NotNull String newValue) {
         IdentifiableShortCircuit<VoltageLevel> identifiableShortCircuit = voltageLevel.getExtension(IdentifiableShortCircuit.class);
         VoltageLevelField field = VoltageLevelField.valueOf(voltageLevelField);
         switch (field) {