use model class for request body with additionalProperties (#16613)

* try out simple fix

* add test case

* generate samples

samples/client/petstore/java/apache-httpclient/src/main/java/org/openapitools/client/api/FakeApi.java

@@ -32,6 +32,7 @@ import java.time.OffsetDateTime;
 import org.openapitools.client.model.OuterComposite;
 import org.openapitools.client.model.OuterObjectWithEnumProperty;
 import org.openapitools.client.model.Pet;
+import org.openapitools.client.model.TestInlineFreeformAdditionalPropertiesRequest;
 import org.openapitools.client.model.User;
 
 
@@ -1297,6 +1298,77 @@ if (booleanGroup != null)
 
     
     
+    final String[] localVarAccepts = {
+      
+    };
+    final String localVarAccept = apiClient.selectHeaderAccept(localVarAccepts);
+
+    final String[] localVarContentTypes = {
+      "application/json"
+    };
+    final String localVarContentType = apiClient.selectHeaderContentType(localVarContentTypes);
+
+    String[] localVarAuthNames = new String[] {  };
+
+    apiClient.invokeAPI(
+        localVarPath,
+        "POST",
+        localVarQueryParams,
+        localVarCollectionQueryParams,
+        localVarQueryStringJoiner.toString(),
+        localVarPostBody,
+        localVarHeaderParams,
+        localVarCookieParams,
+        localVarFormParams,
+        localVarAccept,
+        localVarContentType,
+        localVarAuthNames,
+        null
+    );
+  }
+
+  /**
+   * test inline free-form additionalProperties
+   * 
+   * @param testInlineFreeformAdditionalPropertiesRequest request body (required)
+   * @throws ApiException if fails to make API call
+   */
+  public void testInlineFreeformAdditionalProperties(TestInlineFreeformAdditionalPropertiesRequest testInlineFreeformAdditionalPropertiesRequest) throws ApiException {
+    this.testInlineFreeformAdditionalProperties(testInlineFreeformAdditionalPropertiesRequest, Collections.emptyMap());
+  }
+
+
+  /**
+   * test inline free-form additionalProperties
+   * 
+   * @param testInlineFreeformAdditionalPropertiesRequest request body (required)
+   * @param additionalHeaders additionalHeaders for this call
+   * @throws ApiException if fails to make API call
+   */
+  public void testInlineFreeformAdditionalProperties(TestInlineFreeformAdditionalPropertiesRequest testInlineFreeformAdditionalPropertiesRequest, Map<String, String> additionalHeaders) throws ApiException {
+    Object localVarPostBody = testInlineFreeformAdditionalPropertiesRequest;
+    
+    // verify the required parameter 'testInlineFreeformAdditionalPropertiesRequest' is set
+    if (testInlineFreeformAdditionalPropertiesRequest == null) {
+      throw new ApiException(400, "Missing the required parameter 'testInlineFreeformAdditionalPropertiesRequest' when calling testInlineFreeformAdditionalProperties");
+    }
+    
+    // create path and map variables
+    String localVarPath = "/fake/inline-freeform-additionalProperties";
+
+    StringJoiner localVarQueryStringJoiner = new StringJoiner("&");
+    String localVarQueryParameterBaseName;
+    List<Pair> localVarQueryParams = new ArrayList<Pair>();
+    List<Pair> localVarCollectionQueryParams = new ArrayList<Pair>();
+    Map<String, String> localVarHeaderParams = new HashMap<String, String>();
+    Map<String, String> localVarCookieParams = new HashMap<String, String>();
+    Map<String, Object> localVarFormParams = new HashMap<String, Object>();
+
+    
+    localVarHeaderParams.putAll(additionalHeaders);
+
+    
+    
     final String[] localVarAccepts = {
       
     };

samples/client/petstore/java/apache-httpclient/src/main/java/org/openapitools/client/model/TestInlineFreeformAdditionalPropertiesRequest.java

@@ -0,0 +1,157 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client.model;
+
+import java.util.Objects;
+import java.util.Arrays;
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonTypeName;
+import com.fasterxml.jackson.annotation.JsonValue;
+import java.util.HashMap;
+import java.util.Map;
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+import com.fasterxml.jackson.annotation.JsonTypeName;
+import java.io.UnsupportedEncodingException;
+import java.net.URLEncoder;
+import java.util.StringJoiner;
+
+/**
+ * TestInlineFreeformAdditionalPropertiesRequest
+ */
+@JsonPropertyOrder({
+  TestInlineFreeformAdditionalPropertiesRequest.JSON_PROPERTY_SOME_PROPERTY
+})
+@JsonTypeName("testInlineFreeformAdditionalProperties_request")
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
+public class TestInlineFreeformAdditionalPropertiesRequest extends HashMap<String, Object> {
+  public static final String JSON_PROPERTY_SOME_PROPERTY = "someProperty";
+  private String someProperty;
+
+  public TestInlineFreeformAdditionalPropertiesRequest() {
+
+  }
+
+  public TestInlineFreeformAdditionalPropertiesRequest someProperty(String someProperty) {
+    
+    this.someProperty = someProperty;
+    return this;
+  }
+
+   /**
+   * Get someProperty
+   * @return someProperty
+  **/
+  @javax.annotation.Nullable
+  @JsonProperty(JSON_PROPERTY_SOME_PROPERTY)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public String getSomeProperty() {
+    return someProperty;
+  }
+
+
+  @JsonProperty(JSON_PROPERTY_SOME_PROPERTY)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+  public void setSomeProperty(String someProperty) {
+    this.someProperty = someProperty;
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    TestInlineFreeformAdditionalPropertiesRequest testInlineFreeformAdditionalPropertiesRequest = (TestInlineFreeformAdditionalPropertiesRequest) o;
+    return Objects.equals(this.someProperty, testInlineFreeformAdditionalPropertiesRequest.someProperty) &&
+        super.equals(o);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(someProperty, super.hashCode());
+  }
+
+  @Override
+  public String toString() {
+    StringBuilder sb = new StringBuilder();
+    sb.append("class TestInlineFreeformAdditionalPropertiesRequest {\n");
+    sb.append("    ").append(toIndentedString(super.toString())).append("\n");
+    sb.append("    someProperty: ").append(toIndentedString(someProperty)).append("\n");
+    sb.append("}");
+    return sb.toString();
+  }
+
+  /**
+   * Convert the given object to string with each line indented by 4 spaces
+   * (except the first line).
+   */
+  private String toIndentedString(Object o) {
+    if (o == null) {
+      return "null";
+    }
+    return o.toString().replace("\n", "\n    ");
+  }
+
+  /**
+   * Convert the instance into URL query string.
+   *
+   * @return URL query string
+   */
+  public String toUrlQueryString() {
+    return toUrlQueryString(null);
+  }
+
+  /**
+   * Convert the instance into URL query string.
+   *
+   * @param prefix prefix of the query string
+   * @return URL query string
+   */
+  public String toUrlQueryString(String prefix) {
+    String suffix = "";
+    String containerSuffix = "";
+    String containerPrefix = "";
+    if (prefix == null) {
+      // style=form, explode=true, e.g. /pet?name=cat&type=manx
+      prefix = "";
+    } else {
+      // deepObject style e.g. /pet?id[name]=cat&id[type]=manx
+      prefix = prefix + "[";
+      suffix = "]";
+      containerSuffix = "]";
+      containerPrefix = "[";
+    }
+
+    StringJoiner joiner = new StringJoiner("&");
+
+    // add `someProperty` to the URL query string
+    if (getSomeProperty() != null) {
+      try {
+        joiner.add(String.format("%ssomeProperty%s=%s", prefix, suffix, URLEncoder.encode(String.valueOf(getSomeProperty()), "UTF-8").replaceAll("\\+", "%20")));
+      } catch (UnsupportedEncodingException e) {
+        // Should never happen, UTF-8 is always supported
+        throw new RuntimeException(e);
+      }
+    }
+
+    return joiner.toString();
+  }
+
+}
+

samples/client/petstore/java/apache-httpclient/src/test/java/org/openapitools/client/model/TestInlineFreeformAdditionalPropertiesRequestTest.java

@@ -0,0 +1,49 @@
+/*
+ * OpenAPI Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package org.openapitools.client.model;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonTypeName;
+import com.fasterxml.jackson.annotation.JsonValue;
+import java.util.HashMap;
+import java.util.Map;
+import org.junit.Assert;
+import org.junit.Ignore;
+import org.junit.Test;
+
+/**
+ * Model tests for TestInlineFreeformAdditionalPropertiesRequest
+ */
+public class TestInlineFreeformAdditionalPropertiesRequestTest {
+    private final TestInlineFreeformAdditionalPropertiesRequest model = new TestInlineFreeformAdditionalPropertiesRequest();
+
+    /**
+     * Model tests for TestInlineFreeformAdditionalPropertiesRequest
+     */
+    @Test
+    public void testTestInlineFreeformAdditionalPropertiesRequest() {
+        // TODO: test TestInlineFreeformAdditionalPropertiesRequest
+    }
+
+    /**
+     * Test the property 'someProperty'
+     */
+    @Test
+    public void somePropertyTest() {
+        // TODO: test someProperty
+    }
+
+}