Openapi generator maven plugin generate classes with missing symbol

I use openapi-generator-maven-plugin to generate classes from openapi yml files but in some of them I get this errors:


Cannot find symbol
symbol: method requiredMode()
location: @interface io.swagger.v3.oas.annotations.media.Schema

I checked in io.swagger.v3.oas.annotations.media.Schema and method requiredMode() is really missing.

Below my pom file:

   <?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>
<parent>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-parent</artifactId>
	<version>3.1.0</version>
	<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.maglione</groupId>
<artifactId>contactsapi</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>contactsapi</name>
<description>Demo project </description>
<properties>
	<java.version>17</java.version>
	<openapi-generator.version>6.6.0</openapi-generator.version>
</properties>
<dependencies>
	<dependency>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-data-jdbc</artifactId>
	</dependency>
	<dependency>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-data-jpa</artifactId>
	</dependency>
	<dependency>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-web</artifactId>
	</dependency>
	<dependency>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-validation</artifactId>
	</dependency>
	<dependency>
		<groupId>com.h2database</groupId>
		<artifactId>h2</artifactId>
		<scope>runtime</scope>
	</dependency>
	<dependency>
		<groupId>javax.annotation</groupId>
		<artifactId>javax.annotation-api</artifactId>
		<version>1.3.2</version>
	</dependency>
	<dependency>
		<groupId>javax.validation</groupId>
		<artifactId>validation-api</artifactId>
		<version>1.1.0.Final</version>
	</dependency>
	<dependency>
		<groupId>org.openapitools</groupId>
		<artifactId>jackson-databind-nullable</artifactId>
		<version>0.2.6</version>
	</dependency>
	<dependency>
		<groupId>io.springfox</groupId>
		<artifactId>springfox-swagger2</artifactId>
		<version>3.0.0</version>
	</dependency>
	<dependency>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-test</artifactId>
		<scope>test</scope>
	</dependency>
</dependencies>

<build>
	<plugins>
		<plugin>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-maven-plugin</artifactId>
		</plugin>
		<plugin>
			<groupId>org.openapitools</groupId>
			<artifactId>openapi-generator-maven-plugin</artifactId>
			<version>${openapi-generator.version}</version>
			<executions>
				<execution>
					<goals>
						<goal>generate</goal>
					</goals>
					<configuration>
						<inputSpec>
							 ${project.basedir}/src/main/resources/contactsapi.yml
						</inputSpec>
						<generatorName>spring</generatorName>
						<apiPackage>com.maglione.contactsapi.api</apiPackage>
						<modelPackage>com.maglione.contactsapi.model</modelPackage>
						<supportingFilesToGenerate>
							ApiUtil.java
						</supportingFilesToGenerate>
						<configOptions>
							<delegatePattern>true</delegatePattern>
							<useSpringBoot3>true</useSpringBoot3>

						</configOptions>
					</configuration>
				</execution>
			</executions>
		</plugin>
	</plugins>
</build>

</project>

I tried to search online for possible bug but did not find anything

Welcome to StackOverflow, jack nik!

As Helen mentioned, requiredMode() exists only in newer versions of swagger-annotations.
To check what version your project is using, run mvn dependency:tree. You'll find that swagger-annotations version 2.1.2 is used, as transitively included via springfox-swagger2.

If you remove the supportingFilesToGenerate section from your pom.xml, openapi-generator will create a file .target/generated-sources/openapi/pom.xml that tells you the intended dependencies to be used with the generated code. In your case, these dependencies include io.swagger.core.v3:swagger-core-jakarta:jar:2.2.7, transitively included via org.springdoc:springdoc-openapi-starter-webmvc-ui:jar:2.0.2.

To fix your build, you need to include the newer swagger dependency. And you also need to exclude the old swagger dependency, so that maven knows it has to use the annotations from the new dependency and cannot use the annotations from the old dependency.

So to fix your problem, replace this:

    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-swagger2</artifactId>
        <version>3.0.0</version>
    </dependency>

by this:

        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger2</artifactId>
            <version>3.0.0</version>
            <exclusions>
                <exclusion>
                    <groupId>io.swagger.core.v3</groupId>
                    <artifactId>swagger-annotations</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>io.swagger.core.v3</groupId>
            <artifactId>swagger-core-jakarta</artifactId>
            <version>2.2.7</version>
        </dependency>