Demo for issue openapi-generator-maven-plugin 6.3.0 toUrlQueryString(String)

demo.yaml

openapi: 3.0.1
info:
  title: swagger-server
  description: Demo API
  version: "1.0"
paths:
  /api/all:
    get:
      summary: Retrieve All
      operationId: getAll
      responses:
        "200":
          description: Found stuff
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/DemoObject'
components:
  schemas:
    ArrayItem1:
      required:
        - name
      type: object
      properties:
        field1:
          type: integer
          format: int32
        name:
          type: string
    ArrayItem2:
      required:
        - name
      type: object
      properties:
        field2:
          type: string
        name:
          type: string
    ArrayItem:
      required:
        - name
      type: object
      properties:
        name:
          type: string
      discriminator:
        propertyName: name
      anyOf:
        - $ref: '#/components/schemas/ArrayItem1'
        - $ref: '#/components/schemas/ArrayItem2'
    DemoObject:
      type: object
      properties:
        property1:
          type: boolean
        arrayItems:
          type: array
          items:
            $ref: '#/components/schemas/ArrayItem'

pom.xml

<!-- only the openapi-generator-maven-plugin part -->
            <plugin>
                <groupId>org.openapitools</groupId>
                <artifactId>openapi-generator-maven-plugin</artifactId>
                <version>6.3.0</version>
                <configuration>

                    <generatorName>java</generatorName>
                    <library>native</library>

                    <generateApis>false</generateApis>
                    <generateApiTests>false</generateApiTests>
                    <generateModelTests>false</generateModelTests>
                    <generateApiDocumentation>false</generateApiDocumentation>
                    <generateModelDocumentation>false</generateModelDocumentation>

                    <typeMappings>
                        <typeMapping>OffsetDateTime=LocalDateTime</typeMapping>
                    </typeMappings>
                    <importMappings>
                        <importMapping>java.time.OffsetDateTime=java.time.LocalDateTime</importMapping>
                    </importMappings>
                    <additionalProperties>
                        <additionalProperty>
                            openApiNullable=false
                        </additionalProperty>
                    </additionalProperties>
                </configuration>
                <executions>
                    <execution>
                        <id>generate-demo-models</id>
                        <goals>
                            <goal>generate</goal>
                        </goals>
                        <configuration>
                            <inputSpec>${project.basedir}/src/main/resources/demo.yaml</inputSpec>
                            <packageName>org.example.generated.demo</packageName>
                            <modelPackage>org.example.generated.demo.objects</modelPackage>
                            <apiPackage>org.example.generated.demo.api</apiPackage>
                        </configuration>
                    </execution>
                </executions>
            </plugin>