diff --git a/samples/client/petstore/java/feign/src/main/java/org/openapitools/client/model/OuterObjectWithEnumProperty.java b/samples/client/petstore/java/feign/src/main/java/org/openapitools/client/model/OuterObjectWithEnumProperty.java
index 07a7caa9f08..df0613b94a3 100644
--- a/samples/client/petstore/java/feign/src/main/java/org/openapitools/client/model/OuterObjectWithEnumProperty.java
+++ b/samples/client/petstore/java/feign/src/main/java/org/openapitools/client/model/OuterObjectWithEnumProperty.java
@@ -48,6 +48,7 @@ public class OuterObjectWithEnumProperty {
    * Get value
    * @return value
   **/
+  @javax.annotation.Nonnull
   @ApiModelProperty(required = true, value = "")
   @JsonProperty(JSON_PROPERTY_VALUE)
   @JsonInclude(value = JsonInclude.Include.ALWAYS)
diff --git a/samples/client/petstore/java/webclient/src/main/java/org/openapitools/client/model/OuterObjectWithEnumProperty.java b/samples/client/petstore/java/webclient/src/main/java/org/openapitools/client/model/OuterObjectWithEnumProperty.java
index 07a7caa9f08..df0613b94a3 100644
--- a/samples/client/petstore/java/webclient/src/main/java/org/openapitools/client/model/OuterObjectWithEnumProperty.java
+++ b/samples/client/petstore/java/webclient/src/main/java/org/openapitools/client/model/OuterObjectWithEnumProperty.java
@@ -48,6 +48,7 @@ public class OuterObjectWithEnumProperty {
    * Get value
    * @return value
   **/
+  @javax.annotation.Nonnull
   @ApiModelProperty(required = true, value = "")
   @JsonProperty(JSON_PROPERTY_VALUE)
   @JsonInclude(value = JsonInclude.Include.ALWAYS)