[SPRING][SPRING-CLOUD] Bug generating server code response content type when multiple content type are present

Description

Wrong server code is generated when using multiple content types for different http response codes:

@Validated
@Api(value = "Default", description = "the Default API")
public interface DefaultApi {

     /** ... **/

    @ApiOperation(value = "", nickname = "exportUsers", notes = "", response = byte[].class, tags={  })
    @ApiResponses(value = { 
        @ApiResponse(code = 200, message = "Successful operation", response = byte[].class),
        @ApiResponse(code = 500, message = "Internal server error", response = InlineResponse500.class) })
    @RequestMapping(value = "/api/v1/export/users",
        produces = "application/json", 
        method = RequestMethod.GET)
    default ResponseEntity<byte[]> exportUsers() { /** ... **/ }
}

What I am expecting is that @RequestMapping should not define "produces" field, while @ApiResponse should declare a different Content for every response code.

Swagger-codegen version

swagger-codegen-maven-plugin 3.0.52

Swagger declaration file content or url

openapi: 3.0.3
info:
  title: Spring cloud codegen bug
  version: 1.0.0
paths:
  /api/v1/export/users:
    get:
      operationId: exportUsers
      responses:
        '200':
          description: Successful operation
          content:
            application/vnd.openxmlformats-officedocument.spreadsheetml.sheet:
              schema:
                type: string
                format: byte
        '500':
          description: Internal server error
          content:
            application/json:
              schema:
                type: object
                properties:
                  reason:
                    type: string
                  description:
                    type: string

Command line used for generation

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.example</groupId>
    <artifactId>my-library</artifactId>
    <version>1.0.0-SNAPSHOT</version>

    <properties>
        <spring-boot.version>3.2.1</spring-boot.version>
        <spring-cloud.version>2023.0.0</spring-cloud.version>
        <jackson.version>2.15.3</jackson.version>
        <swagger-codegen-plugin.version>3.0.52</swagger-codegen-plugin.version>

        <openapi.package>${project.groupId}.library</openapi.package>
        <openapi.model.package>${openapi.package}.api</openapi.model.package>
        <openapi.client.package>${openapi.package}.client</openapi.client.package>
        <openapi.invoker.package>${openapi.package}.invoker</openapi.invoker.package>
        <openapi.file.name>api.yaml</openapi.file.name>
    </properties>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>${spring-boot.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
            <version>${spring-boot.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-security</artifactId>
            <version>2.2.5.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security.oauth</groupId>
            <artifactId>spring-security-oauth2</artifactId>
            <version>2.5.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>4.0.1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.oltu.oauth2</groupId>
            <artifactId>org.apache.oltu.oauth2.client</artifactId>
            <version>1.0.2</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.datatype</groupId>
            <artifactId>jackson-datatype-jsr310</artifactId>
            <version>2.16.0</version>
        </dependency>
        <dependency>
            <groupId>javax.validation</groupId>
            <artifactId>validation-api</artifactId>
            <version>2.0.1.Final</version>
        </dependency>
        <dependency>
            <groupId>io.swagger</groupId>
            <artifactId>swagger-annotations</artifactId>
            <version>1.6.12</version>
        </dependency>
        <dependency>
            <groupId>io.swagger.core.v3</groupId>
            <artifactId>swagger-annotations</artifactId>
            <version>2.2.19</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>${jackson.version}</version>
        </dependency>
        <dependency>
            <groupId>io.github.openfeign</groupId>
            <artifactId>feign-jackson</artifactId>
            <version>13.1</version>
        </dependency>
    </dependencies>

    <build>
        <pluginManagement>
            <plugins>
                <plugin>
                    <groupId>io.swagger.codegen.v3</groupId>
                    <artifactId>swagger-codegen-maven-plugin</artifactId>
                    <version>${swagger-codegen-plugin.version}</version>
                    <executions>
                        <execution>
                            <id>java-model-generation</id>
                            <phase>generate-sources</phase>
                            <goals>
                                <goal>generate</goal>
                            </goals>
                            <configuration>
                                <language>spring</language>
                                <library>spring-cloud</library>
                                <generateApis>true</generateApis>
                                <generateSupportingFiles>true</generateSupportingFiles>
                                <inputSpec>${project.basedir}/src/main/resources/${openapi.file.name}</inputSpec>
                                <output>${project.build.directory}/generated-sources/swagger</output>
                                <modelPackage>${openapi.model.package}</modelPackage>
                                <apiPackage>${openapi.client.package}</apiPackage>
                                <invokerPackage>${openapi.invoker.package}</invokerPackage>
                                <configOptions>
                                    <generateForOpenFeign>true</generateForOpenFeign>
                                    <dateLibrary>java8</dateLibrary>
                                    <sourceFolder>src/main/java</sourceFolder>
                                    <hideGenerationTimestamp>true</hideGenerationTimestamp>
                                    <annotationLibrary>swagger3</annotationLibrary>
                                    <serializableModel>true</serializableModel>
                                    <serializationLibrary>jackson</serializationLibrary>
                                    <additionalEnumTypeAnnotations>true</additionalEnumTypeAnnotations>
                                    <useJakartaEe>true</useJakartaEe>
                                    <useSpringBoot3>true</useSpringBoot3>
                                    <useEnumCaseInsensitive>true</useEnumCaseInsensitive>
                                </configOptions>
                                <typeMappings>
                                    <typeMapping>Double=java.math.BigDecimal</typeMapping>
                                </typeMappings>
                                <importMappings>
                                    <importMapping>GregorianCalendar=java.util.GregorianCalendar</importMapping>
                                </importMappings>
                            </configuration>
                        </execution>
                    </executions>
                </plugin>
            </plugins>
        </pluginManagement>

        <plugins>
            <plugin>
                <groupId>io.swagger.codegen.v3</groupId>
                <artifactId>swagger-codegen-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

Steps to reproduce

Create a maven project with the following directory structure:

my-library
├── pom.xml
├── src
    ├── main
        ├── resources
            ├── api.yaml

Run:

mvn install

And check ./$OUTPUT_DIR/generated-sources/swagger/src/main/java/com/example/library/client/DefaultApi.java

Suggest a fix/enhancement

This bug probably happens because the wrong version of @ApiResponse is being used for generating the server code. As a matter of fact both io.swagger.swagger-annotations and io.swagger.core.v3.swagger-annotations need to be imported.

• https://docs.swagger.io/swagger-core/v1.5.0/apidocs/io/swagger/annotations/ApiResponse.html
• https://docs.swagger.io/swagger-core/v2.1.1/apidocs/io/swagger/v3/oas/annotations/responses/ApiResponse.html

Start by running mvn install with the provided pom.xml and src/main/resources/api.yaml, then inspect the generated DefaultApi.java under generated-sources/swagger. Compare the generated @RequestMapping and response annotations with the issue's expected per-response content types; done means the output preserves the distinct response content types without an incorrect produces value.