diff --git a/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/JavascriptClientCodegen.java b/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/JavascriptClientCodegen.java
index 3bd7fe4ac74..f921b02cd78 100644
--- a/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/JavascriptClientCodegen.java
+++ b/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/JavascriptClientCodegen.java
@@ -339,10 +339,10 @@ public String toDefaultValue(Property p) {
 
     @Override
     public String toDefaultValueWithParam(String name, Property p) {
+        String type = normalizeType(getTypeDeclaration(p));
         if (p instanceof RefProperty) {
-            return ".constructFromObject(data['" + name + "']);";
+            return " = " + type + ".constructFromObject(data['" + name + "']);";
         } else {
-          String type = normalizeType(getTypeDeclaration(p));
           return " = ApiClient.convertToType(data['" + name + "'], " + type + ");";
         }
     }
diff --git a/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache b/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache
index 38867a6f341..14239caf455 100644
--- a/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache
+++ b/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache
@@ -262,8 +262,7 @@
       default:
         if (typeof type === 'function') {
           // for model type like: User
-          var model = new type();
-          model.constructFromObject(data);
+          var model = type.constructFromObject(data);
           return model;
         } else if (Array.isArray(type)) {
           // for array type like: ['String']
diff --git a/modules/swagger-codegen/src/main/resources/Javascript/model.mustache b/modules/swagger-codegen/src/main/resources/Javascript/model.mustache
index fd64156bb52..5592b328cbe 100644
--- a/modules/swagger-codegen/src/main/resources/Javascript/model.mustache
+++ b/modules/swagger-codegen/src/main/resources/Javascript/model.mustache
@@ -35,16 +35,17 @@
     {{/vars}}
   };
 
-  {{classname}}.prototype.constructFromObject = function(data) {
+  {{classname}}.constructFromObject = function(data) {
     if (!data) {
-      return this;
+      return null;
     }
+    var _this = new {{classname}}();
     {{#vars}}
     if (data['{{baseName}}']) {
-      this['{{baseName}}']{{{defaultValueWithParam}}}
+      _this['{{baseName}}']{{{defaultValueWithParam}}}
     }
     {{/vars}}
-    return this;
+    return _this;
   }
 
   {{^omitModelMethods}}
diff --git a/samples/client/petstore/javascript-promise/src/ApiClient.js b/samples/client/petstore/javascript-promise/src/ApiClient.js
index c6843ed7560..353494ea941 100644
--- a/samples/client/petstore/javascript-promise/src/ApiClient.js
+++ b/samples/client/petstore/javascript-promise/src/ApiClient.js
@@ -250,8 +250,7 @@
       default:
         if (typeof type === 'function') {
           // for model type like: User
-          var model = new type();
-          model.constructFromObject(data);
+          var model = type.constructFromObject(data);
           return model;
         } else if (Array.isArray(type)) {
           // for array type like: ['String']
diff --git a/samples/client/petstore/javascript-promise/src/model/Category.js b/samples/client/petstore/javascript-promise/src/model/Category.js
index 26742d7036b..0e63bbd4297 100644
--- a/samples/client/petstore/javascript-promise/src/model/Category.js
+++ b/samples/client/petstore/javascript-promise/src/model/Category.js
@@ -33,23 +33,25 @@
     
   };
 
-  Category.prototype.constructFromObject = function(data) {
+  Category.constructFromObject = function(data) {
     if (!data) {
-      return this;
+      return null;
     }
+    var _this = new Category();
     
     if (data['id']) {
-      this['id'] = ApiClient.convertToType(data['id'], 'Integer');
+      _this['id'] = ApiClient.convertToType(data['id'], 'Integer');
     }
     
     if (data['name']) {
-      this['name'] = ApiClient.convertToType(data['name'], 'String');
+      _this['name'] = ApiClient.convertToType(data['name'], 'String');
     }
     
-    return this;
+    return _this;
   }
 
   
+  
   /**
    * @return {Integer}
    **/
@@ -78,6 +80,7 @@
     this['name'] = name;
   }
   
+  
 
   Category.prototype.toJson = function() {
     return JSON.stringify(this);
diff --git a/samples/client/petstore/javascript-promise/src/model/Order.js b/samples/client/petstore/javascript-promise/src/model/Order.js
index 0d5b90d319a..0632c1d2983 100644
--- a/samples/client/petstore/javascript-promise/src/model/Order.js
+++ b/samples/client/petstore/javascript-promise/src/model/Order.js
@@ -82,39 +82,41 @@ var StatusEnum = function StatusEnum() {
     
   };
 
-  Order.prototype.constructFromObject = function(data) {
+  Order.constructFromObject = function(data) {
     if (!data) {
-      return this;
+      return null;
     }
+    var _this = new Order();
     
     if (data['id']) {
-      this['id'] = ApiClient.convertToType(data['id'], 'Integer');
+      _this['id'] = ApiClient.convertToType(data['id'], 'Integer');
     }
     
     if (data['petId']) {
-      this['petId'] = ApiClient.convertToType(data['petId'], 'Integer');
+      _this['petId'] = ApiClient.convertToType(data['petId'], 'Integer');
     }
     
     if (data['quantity']) {
-      this['quantity'] = ApiClient.convertToType(data['quantity'], 'Integer');
+      _this['quantity'] = ApiClient.convertToType(data['quantity'], 'Integer');
     }
     
     if (data['shipDate']) {
-      this['shipDate'] = ApiClient.convertToType(data['shipDate'], 'Date');
+      _this['shipDate'] = ApiClient.convertToType(data['shipDate'], 'Date');
     }
     
     if (data['status']) {
-      this['status'] = ApiClient.convertToType(data['status'], 'String');
+      _this['status'] = ApiClient.convertToType(data['status'], 'String');
     }
     
     if (data['complete']) {
-      this['complete'] = ApiClient.convertToType(data['complete'], 'Boolean');
+      _this['complete'] = ApiClient.convertToType(data['complete'], 'Boolean');
     }
     
-    return this;
+    return _this;
   }
 
   
+  
   /**
    * @return {Integer}
    **/
@@ -201,6 +203,7 @@ var StatusEnum = function StatusEnum() {
     this['complete'] = complete;
   }
   
+  
 
   Order.prototype.toJson = function() {
     return JSON.stringify(this);
diff --git a/samples/client/petstore/javascript-promise/src/model/Pet.js b/samples/client/petstore/javascript-promise/src/model/Pet.js
index 67bacb19390..2d1212f5431 100644
--- a/samples/client/petstore/javascript-promise/src/model/Pet.js
+++ b/samples/client/petstore/javascript-promise/src/model/Pet.js
@@ -84,39 +84,41 @@ var StatusEnum = function StatusEnum() {
     
   };
 
-  Pet.prototype.constructFromObject = function(data) {
+  Pet.constructFromObject = function(data) {
     if (!data) {
-      return this;
+      return null;
     }
+    var _this = new Pet();
     
     if (data['id']) {
-      this['id'] = ApiClient.convertToType(data['id'], 'Integer');
+      _this['id'] = ApiClient.convertToType(data['id'], 'Integer');
     }
     
     if (data['category']) {
-      this['category'].constructFromObject(data['category']);
+      _this['category'] = Category.constructFromObject(data['category']);
     }
     
     if (data['name']) {
-      this['name'] = ApiClient.convertToType(data['name'], 'String');
+      _this['name'] = ApiClient.convertToType(data['name'], 'String');
     }
     
     if (data['photoUrls']) {
-      this['photoUrls'] = ApiClient.convertToType(data['photoUrls'], ['String']);
+      _this['photoUrls'] = ApiClient.convertToType(data['photoUrls'], ['String']);
     }
     
     if (data['tags']) {
-      this['tags'] = ApiClient.convertToType(data['tags'], [Tag]);
+      _this['tags'] = ApiClient.convertToType(data['tags'], [Tag]);
     }
     
     if (data['status']) {
-      this['status'] = ApiClient.convertToType(data['status'], 'String');
+      _this['status'] = ApiClient.convertToType(data['status'], 'String');
     }
     
-    return this;
+    return _this;
   }
 
   
+  
   /**
    * @return {Integer}
    **/
@@ -203,6 +205,7 @@ var StatusEnum = function StatusEnum() {
     this['status'] = status;
   }
   
+  
 
   Pet.prototype.toJson = function() {
     return JSON.stringify(this);
diff --git a/samples/client/petstore/javascript-promise/src/model/Tag.js b/samples/client/petstore/javascript-promise/src/model/Tag.js
index 563c1ee9df8..f2451493103 100644
--- a/samples/client/petstore/javascript-promise/src/model/Tag.js
+++ b/samples/client/petstore/javascript-promise/src/model/Tag.js
@@ -33,23 +33,25 @@
     
   };
 
-  Tag.prototype.constructFromObject = function(data) {
+  Tag.constructFromObject = function(data) {
     if (!data) {
-      return this;
+      return null;
     }
+    var _this = new Tag();
     
     if (data['id']) {
-      this['id'] = ApiClient.convertToType(data['id'], 'Integer');
+      _this['id'] = ApiClient.convertToType(data['id'], 'Integer');
     }
     
     if (data['name']) {
-      this['name'] = ApiClient.convertToType(data['name'], 'String');
+      _this['name'] = ApiClient.convertToType(data['name'], 'String');
     }
     
-    return this;
+    return _this;
   }
 
   
+  
   /**
    * @return {Integer}
    **/
@@ -78,6 +80,7 @@
     this['name'] = name;
   }
   
+  
 
   Tag.prototype.toJson = function() {
     return JSON.stringify(this);
diff --git a/samples/client/petstore/javascript-promise/src/model/User.js b/samples/client/petstore/javascript-promise/src/model/User.js
index 67c45561d3c..68dfc609d55 100644
--- a/samples/client/petstore/javascript-promise/src/model/User.js
+++ b/samples/client/petstore/javascript-promise/src/model/User.js
@@ -64,47 +64,49 @@
     
   };
 
-  User.prototype.constructFromObject = function(data) {
+  User.constructFromObject = function(data) {
     if (!data) {
-      return this;
+      return null;
     }
+    var _this = new User();
     
     if (data['id']) {
-      this['id'] = ApiClient.convertToType(data['id'], 'Integer');
+      _this['id'] = ApiClient.convertToType(data['id'], 'Integer');
     }
     
     if (data['username']) {
-      this['username'] = ApiClient.convertToType(data['username'], 'String');
+      _this['username'] = ApiClient.convertToType(data['username'], 'String');
     }
     
     if (data['firstName']) {
-      this['firstName'] = ApiClient.convertToType(data['firstName'], 'String');
+      _this['firstName'] = ApiClient.convertToType(data['firstName'], 'String');
     }
     
     if (data['lastName']) {
-      this['lastName'] = ApiClient.convertToType(data['lastName'], 'String');
+      _this['lastName'] = ApiClient.convertToType(data['lastName'], 'String');
     }
     
     if (data['email']) {
-      this['email'] = ApiClient.convertToType(data['email'], 'String');
+      _this['email'] = ApiClient.convertToType(data['email'], 'String');
     }
     
     if (data['password']) {
-      this['password'] = ApiClient.convertToType(data['password'], 'String');
+      _this['password'] = ApiClient.convertToType(data['password'], 'String');
     }
     
     if (data['phone']) {
-      this['phone'] = ApiClient.convertToType(data['phone'], 'String');
+      _this['phone'] = ApiClient.convertToType(data['phone'], 'String');
     }
     
     if (data['userStatus']) {
-      this['userStatus'] = ApiClient.convertToType(data['userStatus'], 'Integer');
+      _this['userStatus'] = ApiClient.convertToType(data['userStatus'], 'Integer');
     }
     
-    return this;
+    return _this;
   }
 
   
+  
   /**
    * @return {Integer}
    **/
@@ -219,6 +221,7 @@
     this['userStatus'] = userStatus;
   }
   
+  
 
   User.prototype.toJson = function() {
     return JSON.stringify(this);
diff --git a/samples/client/petstore/javascript/src/ApiClient.js b/samples/client/petstore/javascript/src/ApiClient.js
index a102b4fb0cb..1fea5d003a3 100644
--- a/samples/client/petstore/javascript/src/ApiClient.js
+++ b/samples/client/petstore/javascript/src/ApiClient.js
@@ -250,8 +250,7 @@
       default:
         if (typeof type === 'function') {
           // for model type like: User
-          var model = new type();
-          model.constructFromObject(data);
+          var model = type.constructFromObject(data);
           return model;
         } else if (Array.isArray(type)) {
           // for array type like: ['String']
diff --git a/samples/client/petstore/javascript/src/model/Category.js b/samples/client/petstore/javascript/src/model/Category.js
index 26742d7036b..0e63bbd4297 100644
--- a/samples/client/petstore/javascript/src/model/Category.js
+++ b/samples/client/petstore/javascript/src/model/Category.js
@@ -33,23 +33,25 @@
     
   };
 
-  Category.prototype.constructFromObject = function(data) {
+  Category.constructFromObject = function(data) {
     if (!data) {
-      return this;
+      return null;
     }
+    var _this = new Category();
     
     if (data['id']) {
-      this['id'] = ApiClient.convertToType(data['id'], 'Integer');
+      _this['id'] = ApiClient.convertToType(data['id'], 'Integer');
     }
     
     if (data['name']) {
-      this['name'] = ApiClient.convertToType(data['name'], 'String');
+      _this['name'] = ApiClient.convertToType(data['name'], 'String');
     }
     
-    return this;
+    return _this;
   }
 
   
+  
   /**
    * @return {Integer}
    **/
@@ -78,6 +80,7 @@
     this['name'] = name;
   }
   
+  
 
   Category.prototype.toJson = function() {
     return JSON.stringify(this);
diff --git a/samples/client/petstore/javascript/src/model/Order.js b/samples/client/petstore/javascript/src/model/Order.js
index 0d5b90d319a..0632c1d2983 100644
--- a/samples/client/petstore/javascript/src/model/Order.js
+++ b/samples/client/petstore/javascript/src/model/Order.js
@@ -82,39 +82,41 @@ var StatusEnum = function StatusEnum() {
     
   };
 
-  Order.prototype.constructFromObject = function(data) {
+  Order.constructFromObject = function(data) {
     if (!data) {
-      return this;
+      return null;
     }
+    var _this = new Order();
     
     if (data['id']) {
-      this['id'] = ApiClient.convertToType(data['id'], 'Integer');
+      _this['id'] = ApiClient.convertToType(data['id'], 'Integer');
     }
     
     if (data['petId']) {
-      this['petId'] = ApiClient.convertToType(data['petId'], 'Integer');
+      _this['petId'] = ApiClient.convertToType(data['petId'], 'Integer');
     }
     
     if (data['quantity']) {
-      this['quantity'] = ApiClient.convertToType(data['quantity'], 'Integer');
+      _this['quantity'] = ApiClient.convertToType(data['quantity'], 'Integer');
     }
     
     if (data['shipDate']) {
-      this['shipDate'] = ApiClient.convertToType(data['shipDate'], 'Date');
+      _this['shipDate'] = ApiClient.convertToType(data['shipDate'], 'Date');
     }
     
     if (data['status']) {
-      this['status'] = ApiClient.convertToType(data['status'], 'String');
+      _this['status'] = ApiClient.convertToType(data['status'], 'String');
     }
     
     if (data['complete']) {
-      this['complete'] = ApiClient.convertToType(data['complete'], 'Boolean');
+      _this['complete'] = ApiClient.convertToType(data['complete'], 'Boolean');
     }
     
-    return this;
+    return _this;
   }
 
   
+  
   /**
    * @return {Integer}
    **/
@@ -201,6 +203,7 @@ var StatusEnum = function StatusEnum() {
     this['complete'] = complete;
   }
   
+  
 
   Order.prototype.toJson = function() {
     return JSON.stringify(this);
diff --git a/samples/client/petstore/javascript/src/model/Pet.js b/samples/client/petstore/javascript/src/model/Pet.js
index 67bacb19390..2d1212f5431 100644
--- a/samples/client/petstore/javascript/src/model/Pet.js
+++ b/samples/client/petstore/javascript/src/model/Pet.js
@@ -84,39 +84,41 @@ var StatusEnum = function StatusEnum() {
     
   };
 
-  Pet.prototype.constructFromObject = function(data) {
+  Pet.constructFromObject = function(data) {
     if (!data) {
-      return this;
+      return null;
     }
+    var _this = new Pet();
     
     if (data['id']) {
-      this['id'] = ApiClient.convertToType(data['id'], 'Integer');
+      _this['id'] = ApiClient.convertToType(data['id'], 'Integer');
     }
     
     if (data['category']) {
-      this['category'].constructFromObject(data['category']);
+      _this['category'] = Category.constructFromObject(data['category']);
     }
     
     if (data['name']) {
-      this['name'] = ApiClient.convertToType(data['name'], 'String');
+      _this['name'] = ApiClient.convertToType(data['name'], 'String');
     }
     
     if (data['photoUrls']) {
-      this['photoUrls'] = ApiClient.convertToType(data['photoUrls'], ['String']);
+      _this['photoUrls'] = ApiClient.convertToType(data['photoUrls'], ['String']);
     }
     
     if (data['tags']) {
-      this['tags'] = ApiClient.convertToType(data['tags'], [Tag]);
+      _this['tags'] = ApiClient.convertToType(data['tags'], [Tag]);
     }
     
     if (data['status']) {
-      this['status'] = ApiClient.convertToType(data['status'], 'String');
+      _this['status'] = ApiClient.convertToType(data['status'], 'String');
     }
     
-    return this;
+    return _this;
   }
 
   
+  
   /**
    * @return {Integer}
    **/
@@ -203,6 +205,7 @@ var StatusEnum = function StatusEnum() {
     this['status'] = status;
   }
   
+  
 
   Pet.prototype.toJson = function() {
     return JSON.stringify(this);
diff --git a/samples/client/petstore/javascript/src/model/Tag.js b/samples/client/petstore/javascript/src/model/Tag.js
index 563c1ee9df8..f2451493103 100644
--- a/samples/client/petstore/javascript/src/model/Tag.js
+++ b/samples/client/petstore/javascript/src/model/Tag.js
@@ -33,23 +33,25 @@
     
   };
 
-  Tag.prototype.constructFromObject = function(data) {
+  Tag.constructFromObject = function(data) {
     if (!data) {
-      return this;
+      return null;
     }
+    var _this = new Tag();
     
     if (data['id']) {
-      this['id'] = ApiClient.convertToType(data['id'], 'Integer');
+      _this['id'] = ApiClient.convertToType(data['id'], 'Integer');
     }
     
     if (data['name']) {
-      this['name'] = ApiClient.convertToType(data['name'], 'String');
+      _this['name'] = ApiClient.convertToType(data['name'], 'String');
     }
     
-    return this;
+    return _this;
   }
 
   
+  
   /**
    * @return {Integer}
    **/
@@ -78,6 +80,7 @@
     this['name'] = name;
   }
   
+  
 
   Tag.prototype.toJson = function() {
     return JSON.stringify(this);
diff --git a/samples/client/petstore/javascript/src/model/User.js b/samples/client/petstore/javascript/src/model/User.js
index 67c45561d3c..68dfc609d55 100644
--- a/samples/client/petstore/javascript/src/model/User.js
+++ b/samples/client/petstore/javascript/src/model/User.js
@@ -64,47 +64,49 @@
     
   };
 
-  User.prototype.constructFromObject = function(data) {
+  User.constructFromObject = function(data) {
     if (!data) {
-      return this;
+      return null;
     }
+    var _this = new User();
     
     if (data['id']) {
-      this['id'] = ApiClient.convertToType(data['id'], 'Integer');
+      _this['id'] = ApiClient.convertToType(data['id'], 'Integer');
     }
     
     if (data['username']) {
-      this['username'] = ApiClient.convertToType(data['username'], 'String');
+      _this['username'] = ApiClient.convertToType(data['username'], 'String');
     }
     
     if (data['firstName']) {
-      this['firstName'] = ApiClient.convertToType(data['firstName'], 'String');
+      _this['firstName'] = ApiClient.convertToType(data['firstName'], 'String');
     }
     
     if (data['lastName']) {
-      this['lastName'] = ApiClient.convertToType(data['lastName'], 'String');
+      _this['lastName'] = ApiClient.convertToType(data['lastName'], 'String');
     }
     
     if (data['email']) {
-      this['email'] = ApiClient.convertToType(data['email'], 'String');
+      _this['email'] = ApiClient.convertToType(data['email'], 'String');
     }
     
     if (data['password']) {
-      this['password'] = ApiClient.convertToType(data['password'], 'String');
+      _this['password'] = ApiClient.convertToType(data['password'], 'String');
     }
     
     if (data['phone']) {
-      this['phone'] = ApiClient.convertToType(data['phone'], 'String');
+      _this['phone'] = ApiClient.convertToType(data['phone'], 'String');
     }
     
     if (data['userStatus']) {
-      this['userStatus'] = ApiClient.convertToType(data['userStatus'], 'Integer');
+      _this['userStatus'] = ApiClient.convertToType(data['userStatus'], 'Integer');
     }
     
-    return this;
+    return _this;
   }
 
   
+  
   /**
    * @return {Integer}
    **/
@@ -219,6 +221,7 @@
     this['userStatus'] = userStatus;
   }
   
+  
 
   User.prototype.toJson = function() {
     return JSON.stringify(this);