[JAVA] Model not correctly generated

Description

Some generated model code seems to be missing properties, ProcessInstanceDto for example. Generating it with maven plugin. openapi-codegen generates these models correctly.

Swagger-codegen version

3.0.34

Swagger declaration file content or url

openapi.json is packed in camunda-engine-rest-openapi jar.

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<artifactId>camunda-test-client</artifactId>
	<groupId>io.test</groupId>
	<version>0.0.1</version>
	<packaging>jar</packaging>

	<properties>
		<maven.compiler.source>17</maven.compiler.source>
		<maven.compiler.target>17</maven.compiler.target>
		<source.generated.swagger.main>src/java/main</source.generated.swagger.main>
		<source.generated.swagger>${project.build.directory}/generated-sources/swagger</source.generated.swagger>
		<source.generated>${project.build.directory}/generated-sources/</source.generated>
		<camunda.version>7.16.0</camunda.version>
		<spring.version>5.3.20</spring.version>
	</properties>

	<dependencyManagement>
		<dependencies>
			<dependency>
				<groupId>com.fasterxml.jackson</groupId>
				<artifactId>jackson-bom</artifactId>
				<version>2.10.1</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
		</dependencies>
	</dependencyManagement>

	<dependencies>
		<!-- DEPENDENCIES REQUIRED FOR CODE GENERATION -->
		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
			<version>1.18.24</version>
		</dependency>

		<!-- swagger -->
		<dependency>
			<groupId>io.swagger.core.v3</groupId>
			<artifactId>swagger-annotations</artifactId>
			<version>2.2.1</version>
		</dependency>

		<!-- HTTP client: Spring RestTemplate -->
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-context</artifactId>
			<version>${spring.version}</version>
		</dependency>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-web</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<!-- JSON processing: jackson -->
		<dependency>
			<groupId>com.fasterxml.jackson.core</groupId>
			<artifactId>jackson-core</artifactId>
		</dependency>
		<dependency>
			<groupId>com.fasterxml.jackson.core</groupId>
			<artifactId>jackson-annotations</artifactId>
		</dependency>
		<dependency>
			<groupId>com.fasterxml.jackson.core</groupId>
			<artifactId>jackson-databind</artifactId>
		</dependency>
		<dependency>
			<groupId>com.fasterxml.jackson.jaxrs</groupId>
			<artifactId>jackson-jaxrs-json-provider</artifactId>
		</dependency>
		<dependency>
			<groupId>com.fasterxml.jackson.datatype</groupId>
			<artifactId>jackson-datatype-jsr310</artifactId>
		</dependency>
		<dependency>
			<groupId>javax.annotation</groupId>
			<artifactId>javax.annotation-api</artifactId>
			<version>1.3.2</version>
		</dependency>
	</dependencies>

	<build>
		<finalName>${project.artifactId}</finalName>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-dependency-plugin</artifactId>
				<executions>
					<execution>
						<id>unpack-dependencies</id>
						<phase>initialize</phase>
						<goals>
							<goal>unpack</goal>
						</goals>
						<configuration>
							<artifactItems>
								<artifactItem>
									<groupId>org.camunda.bpm</groupId>
									<artifactId>camunda-engine-rest-openapi</artifactId>
									<version>${camunda.version}</version>
									<type>jar</type>
									<includes>openapi.json</includes>
								</artifactItem>
							</artifactItems>
							<outputDirectory>${project.build.directory}/resources</outputDirectory>
						</configuration>
					</execution>
				</executions>
			</plugin>

			<plugin>
				<groupId>io.swagger.codegen.v3</groupId>
				<artifactId>swagger-codegen-maven-plugin</artifactId>
				<executions>
					<execution>
						<goals>
							<goal>generate</goal>
						</goals>
						<phase>generate-sources</phase>
						<configuration>
							<inputSpec>${project.build.directory}/resources/openapi.json</inputSpec>
							<language>java</language>
							<library>resttemplate</library>
							<invokerPackage>io.camunda.client.invoker</invokerPackage>
							<apiPackage>io.camunda.client.api</apiPackage>
							<modelPackage>io.camunda.client.dto</modelPackage>
							<generateApiTests>false</generateApiTests>
							<generateApiDocumentation>false</generateApiDocumentation>
							<generateModelTests>false</generateModelTests>
							<generateModelDocumentation>false</generateModelDocumentation>
							<generateSupportingFiles>true</generateSupportingFiles>
							<configOptions>
								<interfaceOnly>true</interfaceOnly>
								<sourceFolder>${source.generated.swagger.main}</sourceFolder>
								<java8>true</java8>
								<dateLibrary>java8</dateLibrary>
							</configOptions>
						</configuration>
					</execution>
				</executions>
			</plugin>
		</plugins>
	</build>
</project>

Command line used for generation

mvn compile

Steps to reproduce

Tried cleaning and recompiling, seems to happen every time.

Reproduce the report with the Maven plugin and mvn compile, using openapi.json from the camunda-engine-rest-openapi jar. Compare the generated ProcessInstanceDto properties with the declarations in openapi.json and with the output from openapi-codegen; done means the missing model properties are accounted for and generated correctly.