Initially we had swagger-codegen 2.4.22 in our project. We have customized the generator as per requirement with below set of code. Which was working fine.

<java jar="@{baseDir}/lib/swagger-custom-codegen.jar" fork="true" failonerror="true">
      <arg line="generate"/>
      <arg line="-l de.hybris.platform.XXXXX.swagger.XXXXCodegen"/>
      <arg line="-i @{templateDir}/@{version}/@{file}"/>
      <arg line="-o @{baseDir}/gensrc/"/>
      <arg line="-c @{baseDir}/resources/swaggerconfig/@{version}/swagger-generator-config.json"/>
      <arg line="--model-package @{defaultPackage}.@{version}.dto"/>
      <arg line="--api-package @{defaultPackage}.@{version}.api"/>
</java>

Now we are upgrading to swagger-codegen 3.0.31 and above piece of code is failing with below error.

[echo] building extension 'XXXXX'...
[java] Exception in thread "main" java.lang.RuntimeException: Can't load config class with name de.hybris.platform.XXXXX.swagger.XXXXCodegen Available: dart

[java]     at io.swagger.codegen.v3.CodegenConfigLoader.forName(CodegenConfigLoader.java:31)
[java]     at io.swagger.codegen.v3.cli.SwaggerCodegen.main(SwaggerCodegen.java:96)
[java] Caused by: java.lang.ClassCastException: class de.hybris.platform.XXXXX.swagger.XXXXCodegen  cannot be cast to class io.swagger.codegen.v3.CodegenConfig (de.hybris.platform.XXXXX.swagger.XXXXCodegen and io.swagger.codegen.v3.CodegenConfig are in unnamed module of loader 'app')
[java]     at io.swagger.codegen.v3.CodegenConfigLoader.forName(CodegenConfigLoader.java:29)
[java]     ... 1 more

BUILD FAILED

What is going wrong here?