diff --git a/modules/swagger-codegen/src/main/resources/Java/libraries/okhttp-gson/ApiClient.mustache b/modules/swagger-codegen/src/main/resources/Java/libraries/okhttp-gson/ApiClient.mustache
index 82f108ad8f5..8309da3e5d5 100644
--- a/modules/swagger-codegen/src/main/resources/Java/libraries/okhttp-gson/ApiClient.mustache
+++ b/modules/swagger-codegen/src/main/resources/Java/libraries/okhttp-gson/ApiClient.mustache
@@ -60,6 +60,11 @@ public class ApiClient {
 
     private Map<String, Authentication> authentications;
 
+    private DateFormat dateFormat;
+    private DateFormat datetimeFormat;
+    private boolean lenientDatetimeFormat;
+    private int dateLength;
+
     private InputStream sslCaCert;
     private boolean verifyingSsl;
     private KeyManager[] keyManagers;
diff --git a/samples/client/petstore/java/okhttp-gson-parcelableModel/src/main/java/io/swagger/client/ApiClient.java b/samples/client/petstore/java/okhttp-gson-parcelableModel/src/main/java/io/swagger/client/ApiClient.java
index 1fbf625b4ec..132462af980 100644
--- a/samples/client/petstore/java/okhttp-gson-parcelableModel/src/main/java/io/swagger/client/ApiClient.java
+++ b/samples/client/petstore/java/okhttp-gson-parcelableModel/src/main/java/io/swagger/client/ApiClient.java
@@ -59,6 +59,11 @@ public class ApiClient {
 
     private Map<String, Authentication> authentications;
 
+    private DateFormat dateFormat;
+    private DateFormat datetimeFormat;
+    private boolean lenientDatetimeFormat;
+    private int dateLength;
+
     private InputStream sslCaCert;
     private boolean verifyingSsl;
     private KeyManager[] keyManagers;
diff --git a/samples/client/petstore/java/okhttp-gson/src/main/java/io/swagger/client/ApiClient.java b/samples/client/petstore/java/okhttp-gson/src/main/java/io/swagger/client/ApiClient.java
index 1fbf625b4ec..132462af980 100644
--- a/samples/client/petstore/java/okhttp-gson/src/main/java/io/swagger/client/ApiClient.java
+++ b/samples/client/petstore/java/okhttp-gson/src/main/java/io/swagger/client/ApiClient.java
@@ -59,6 +59,11 @@ public class ApiClient {
 
     private Map<String, Authentication> authentications;
 
+    private DateFormat dateFormat;
+    private DateFormat datetimeFormat;
+    private boolean lenientDatetimeFormat;
+    private int dateLength;
+
     private InputStream sslCaCert;
     private boolean verifyingSsl;
     private KeyManager[] keyManagers;