add requiredVars and optionalVars for codegen model

modules/swagger-codegen/src/main/java/io/swagger/codegen/CodegenModel.java

@@ -18,6 +18,8 @@ public class CodegenModel {
     public String discriminator;
     public String defaultValue;
     public List<CodegenProperty> vars = new ArrayList<CodegenProperty>();
+    public List<CodegenProperty> requiredVars = new ArrayList<CodegenProperty>(); // a list of required properties
+    public List<CodegenProperty> optionalVars = new ArrayList<CodegenProperty>(); // a list of optional properties
     public List<CodegenProperty> allVars;
     public List<String> allowableValues;
 

modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultCodegen.java

@@ -2307,6 +2307,12 @@ public class DefaultCodegen {
                 addImport(m, cp.baseType);
                 addImport(m, cp.complexType);
                 vars.add(cp);
+
+                if (Boolean.TRUE.equals(cp.required)) { // if required, add to the list "requiredVars"
+                    m.requiredVars.add(cp);
+                } else { // else add to the list "optionalVars" for optional property
+                    m.optionalVars.add(cp);
+                }
             }
         }
     }

modules/swagger-codegen/src/test/resources/2_0/petstore-with-fake-endpoints-models-for-testing.yaml

@@ -755,6 +755,9 @@ definitions:
     type: object
     required:
       - number
+      - byte
+      - date
+      - password
     properties:
       integer:
         type: integer

samples/client/petstore/php/SwaggerClient-php/README.md

@@ -5,7 +5,7 @@ This PHP package is automatically generated by the [Swagger Codegen](https://git
 
 - API version: 1.0.0
 - Package version: 1.0.0
-- Build date: 2016-04-23T16:49:49.572+08:00
+- Build date: 2016-04-23T22:48:00.795+08:00
 - Build package: class io.swagger.codegen.languages.PhpClientCodegen
 
 ## Requirements

samples/client/petstore/php/SwaggerClient-php/docs/FormatTest.md

@@ -10,11 +10,11 @@ Name | Type | Description | Notes
 **float** | **float** |  | [optional] 
 **double** | **double** |  | [optional] 
 **string** | **string** |  | [optional] 
-**byte** | **string** |  | [optional] 
+**byte** | **string** |  | 
 **binary** | **string** |  | [optional] 
-**date** | [**\DateTime**](Date.md) |  | [optional] 
+**date** | [**\DateTime**](Date.md) |  | 
 **date_time** | [**\DateTime**](\DateTime.md) |  | [optional] 
-**password** | **string** |  | [optional] 
+**password** | **string** |  | 
 
 [[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)