support latest Retrofit 2 v2.0.0-beta4

[dhontecillas]

Retrofit v2.0.0-beta4 introduces some package changes from beta3, that should be reflected in moustache templates.

[wing328]

@dhontecillas thanks for the PR. Please update retrofit2 petstore sample so that CI can verify the change.

Ref: https://github.com/swagger-api/swagger-codegen/blob/master/CONTRIBUTING.md#testing

[DerPate]

Maybe you also push the okhttp version to okhttp3 because the beta4 for retrofit pushes this also to the same version and at least introduced some bugs at my instaltion

[wing328]

Btw, one of your commits (in the Commits tab) is not linked to your account, which means that commit won't count as your contribution in https://github.com/swagger-api/swagger-codegen/graphs/contributors

[cbornet]

I think the okhttp3 dependency should be removed since it is already included in retrofit2

[wing328]

@dhontecillas may I know if you're updating the PR with the feedback from @cbornet and @DerPate? Let us know if you need any help.

[dhontecillas]

I'm sorry, I'm crunching for a release that I have the Feb 24th, so I don't expect to fix the pull request until the end of this week. If that is no problem, I will update it.

[wing328]

Thanks for the update. Please take your time :)

[dhontecillas]

I've updated the tests for retrofit2 library, as suggested in the comments. Can you check everything is ok ?

[wing328]

@dhontecillas I did some tests and found some minor issues:

1. When I ran gradle check under samples/client/petstore/java/retrofit2, I got the following error:

/private/var/tmp/pr/dhontecillas/swagger-codegen/samples/client/petstore/java/retrofit2/src/main/java/io/swagger/client/ApiClient.java:15: error: package retrofit2.converter.gson does not exist
import retrofit2.converter.gson.GsonConverterFactory;
                               ^
/private/var/tmp/pr/dhontecillas/swagger-codegen/samples/client/petstore/java/retrofit2/src/main/java/io/swagger/client/ApiClient.java:324: error: cannot find symbol
      private final GsonConverterFactory gsonConverterFactory;
                    ^
  symbol:   class GsonConverterFactory
  location: class GsonCustomConverterFactory
/private/var/tmp/pr/dhontecillas/swagger-codegen/samples/client/petstore/java/retrofit2/src/main/java/io/swagger/client/ApiClient.java:329: error: cannot find symbol
        this.gsonConverterFactory = GsonConverterFactory.create(gson);
                                    ^

I believe you need to update build.gradle (mustache) as well.

2. I ran ./bin/java-petstore-retrofit2rx.sh and got the following error when running mvn test under samples/client/petstore/java/retrofit2rx

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.3.2:compile (default-compile) on project swagger-petstore-retrofit2-rx: Compilation failure: Compilation failure:
[ERROR] /private/var/tmp/pr/dhontecillas/swagger-codegen/samples/client/petstore/java/retrofit2rx/src/main/java/io/swagger/client/ApiClient.java:[15,31] error: package retrofit2.converter.gson does not exist
[ERROR] /private/var/tmp/pr/dhontecillas/swagger-codegen/samples/client/petstore/java/retrofit2rx/src/main/java/io/swagger/client/ApiClient.java:[324,17] error: cannot find symbol
[ERROR] class GsonCustomConverterFactory
[ERROR] /private/var/tmp/pr/dhontecillas/swagger-codegen/samples/client/petstore/java/retrofit2rx/src/main/java/io/swagger/client/ApiClient.java:[329,33] error: cannot find symbol
[ERROR] class GsonCustomConverterFactory
[ERROR] /private/var/tmp/pr/dhontecillas/swagger-codegen/samples/client/petstore/java/retrofit2rx/src/main/java/io/swagger/client/ApiClient.java:[340,4] error: method does not override or implement a method from a supertype

[dhontecillas]

I fixed the templates but I still have to check the gradle build.

[dhontecillas]

I think that now it should be ok and ready to merge.

[wing328]

@dhontecillas tested again and no longer encountered those issues. Thanks again for the PR.

[dhontecillas]

You are welcome. Thanks for the patience with the not so well done PR :)

[wing328]

Given that it's your first PR to swagger-codegen, it definitely looks good. I hope by now you feel more comfortable making changes to swagger-codegen.

If you're interested in making more enhancements to the Java API client, please refer to https://github.com/swagger-api/swagger-codegen/issues?q=is%3Aopen+label%3A%22Need+community+contribution%22+label%3A%22Client%3A+Java%22