[Java][OkHttp-Gson] fix: free form query parameters for okhttp-gson (#19226)

samples/client/petstore/java/okhttp-gson/docs/DefaultApi.md

@@ -5,6 +5,7 @@ All URIs are relative to *http://petstore.swagger.io:80/v2*
 | Method | HTTP request | Description |
 |------------- | ------------- | -------------|
 | [**fakeAnyOfWIthSameErasureGet**](DefaultApi.md#fakeAnyOfWIthSameErasureGet) | **GET** /fake/anyOfWIthSameErasure |  |
+| [**fakeFreeFormQueryParametersGet**](DefaultApi.md#fakeFreeFormQueryParametersGet) | **GET** /fake/free-form-query-parameters |  |
 | [**fakeOneOfWIthSameErasureGet**](DefaultApi.md#fakeOneOfWIthSameErasureGet) | **GET** /fake/oneOfWIthSameErasure |  |
 | [**fooGet**](DefaultApi.md#fooGet) | **GET** /foo |  |
 
@@ -67,6 +68,67 @@ No authorization required
 |-------------|-------------|------------------|
 | **200** | successful response |  -  |
 
+<a id="fakeFreeFormQueryParametersGet"></a>
+# **fakeFreeFormQueryParametersGet**
+> fakeFreeFormQueryParametersGet(fixed, freeForm)
+
+
+
+### Example
+```java
+// Import classes:
+import org.openapitools.client.ApiClient;
+import org.openapitools.client.ApiException;
+import org.openapitools.client.Configuration;
+import org.openapitools.client.models.*;
+import org.openapitools.client.api.DefaultApi;
+
+public class Example {
+  public static void main(String[] args) {
+    ApiClient defaultClient = Configuration.getDefaultApiClient();
+    defaultClient.setBasePath("http://petstore.swagger.io:80/v2");
+
+    DefaultApi apiInstance = new DefaultApi(defaultClient);
+    String fixed = "fixed_example"; // String | 
+    Object freeForm = null; // Object | 
+    try {
+      apiInstance.fakeFreeFormQueryParametersGet(fixed, freeForm);
+    } catch (ApiException e) {
+      System.err.println("Exception when calling DefaultApi#fakeFreeFormQueryParametersGet");
+      System.err.println("Status code: " + e.getCode());
+      System.err.println("Reason: " + e.getResponseBody());
+      System.err.println("Response headers: " + e.getResponseHeaders());
+      e.printStackTrace();
+    }
+  }
+}
+```
+
+### Parameters
+
+| Name | Type | Description  | Notes |
+|------------- | ------------- | ------------- | -------------|
+| **fixed** | **String**|  | [optional] |
+| **freeForm** | [**Object**](.md)|  | [optional] |
+
+### Return type
+
+null (empty response body)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: Not defined
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | OK |  -  |
+
 <a id="fakeOneOfWIthSameErasureGet"></a>
 # **fakeOneOfWIthSameErasureGet**
 > FakeOneOfWIthSameErasureGet200Response fakeOneOfWIthSameErasureGet()