maven-codegen-plugin Access custom templates from jar

Description

I have following situation

• customCodegen as jar artifact
• customized templates as part of the same jar (similar packaging like with (e.g. adaptedTemplate)
• used customCodegen from swagger-codegen-maven-plugin
• using copy depen -to extract templates to working directory

If I extract and copy adaptedTemplate directory to build path -> it works OK

Swagger-codegen version

3.0.21

Swagger declaration file content or url

Command line used for generation

swagger-codegen-maven-plugin

Steps to reproduce

Related issues/PRs

Suggest a fix/enhancement

Question: is it possible to load modified templates directly from jar file, similar to original swagger-generators ?
Customized codegen code works fine, just to unpack (in many poms is quite tedious :( )

I see problem in https://github.com/swagger-api/swagger-codegen/blob/master/modules/swagger-codegen/src/main/java/io/swagger/codegen/config/CodegenConfigurator.java
at setTemplate expects local directory, or is there any workaround?
Would it be possible to specify jar file access to load modified templates?
( swagger.yml from jar works nice just as dependency in plugin, similar to custom codegen in customgenerator

1. option would be to check local directory existence -> if not expect jar access
2. other - define it alternate ways

(other problems would be to access them in Handlebar, but this I have probably solved, as I had modified HandlebarTemplateEngine search algorithm to access all 4 places, as it was in codegen v2.x )

Overwrite this configurator is neither not so easy, as created in swagger-coden-maven-plugin directly.
Thanks for any hints

Start with modules/swagger-codegen/src/main/java/io/swagger/codegen/config/CodegenConfigurator.java and the swagger-codegen-maven-plugin entry point; compare how setTemplate handles a local directory with the custom codegen JAR setup described. Done means Maven plugin generation can load customized templates directly from the JAR without copy-dependency extraction.