Generated java code does not compile

[dickerpulli]

When I generate java code with java -jar openapi-generator-cli-4.2.3.jar generate -g jaxrs-resteasy -i ../src/main/resources/git-icar/url-schemes/exampleUrlScheme.json -o output the resulting code does not compile.

The Collections (i.e. IcarAnimalCoreCollection) extends IcarResourceCollection that has a member of type List, but i.e. has the same field member of type List.

This does not compile

 .../target/generated-sources/openapi/src/main/java/org/openapitools/model/IcarAnimalCoreCollection.java:[54,15]
 name clash: setMember(java.util.List<org.openapitools.model.IcarAnimalCoreResource>) in org.openapitools.model.IcarAnimalCoreCollection 
and setMember(java.util.List<java.lang.Object>) in org.openapitools.model.IcarResourceCollection have the same erasure, yet neither overrides the other

Do I missed a parameter? Is it a problem of the OpenAPI-Generator? What tool do you use to generate compilable java code (> Java 8)?

[ahokkonen]

@dickerpulli ,with generating .net code I've been using openapi-generator v4.3.0 and it compiled well. I guess @alamers also has used same version for Java generation. Seems like you are using 4.2.3, so at least you could try to update generator.

I would recommend to avoid (at least for now) using latest version of openapi-generation (v4.3.1) as it contains some breaking changes for handling discriminators in schemes.

[alamers]

Hi, I think I did something similar to you when testing this (see #84) and did not run into this problem. I used the default OkHttp generation instead of JAX-RS but I don't think that should completely change the generated code. Also I did use the latest version. Unfortunately, I seem to have done a bit of spring cleaning on my laptop so I don't have the workspace anymore. Let me know if 4.3.1 fixes it for you, otherwise I'll try and reconstruct my previous setup.

[ahokkonen]

@alamers
in 4.3.1 it seems to be some global changes for "discriminator" handling (one we are using for proper inheritance). Please refer to this PR on openapi-generator.

I would recommend to use 4.3.0 instead for now.

[dickerpulli]

I can confirm that currently 4.3.1 does not work at all. But with 4.3.0, 4.2.3, 4.2.2 (that's what i've tested so far) the code is generated but no compileable java code.

When I execute java -jar openapi-generator-cli-4.3.0.jar generate -g java -i ICAR-ADE-1/url-schemes/exampleUrlScheme.json -o output I get the generated code like attached in the output.zip. The same problem i.e. IcarAnimalCoreCollection extends IcarResourceCollection and overrides setMember method incorrectly.

java.util.List<org.openapitools.model.IcarMovementBirthEventResource> is not compatible with java.util.List<java.lang.Object>

output.zip

[dickerpulli]

When I remove the following block from icanResourceCollection.json everythings compiles

    "member": {
      "type": "array",
      "items": {}
    }

As I understand IcarResourceCollection is more or less an abstract Class that holds the view (IcarResourceCollectionView) and is implemented by all collections like IcarAnimalCoreCollection. This implementing collections all have this member property. So I think the member property in their parent class is not neccessary.

What do you think? Does this work with your .NET code? @ahokkonen

[cookeac]

I agree @dickerpulli @ahokkonen the member property of icarResourceCollection was principally added for documentation of the intent for derived classes. The documentation could be retained in the Wiki while the definition in the JSON Schema could be removed to improve code generation.
This should not be a breaking change for ADE-1 as the member property will still be defined in all concrete collections.

[ahokkonen]

When I remove the following block from icanResourceCollection.json everythings compiles

    "member": {
      "type": "array",
      "items": {}
    }

As I understand IcarResourceCollection is more or less an abstract Class that holds the view (IcarResourceCollectionView) and is implemented by all collections like IcarAnimalCoreCollection. This implementing collections all have this member property. So I think the member property in their parent class is not neccessary.

What do you think? Does this work with your .NET code? @ahokkonen

@dickerpulli I was about to suggest same solution you have already found (removing "member" from base class). In .NET sub-class just override "member" property from parent and compiles well.

I agree that we can remove this property in parent as a quick and simple solution. Maybe later we can see if this is somehow solvable as a generic/abstract parent-property. (probably requires generator improvements etc.)

[ahokkonen]

I agree @dickerpulli @ahokkonen the member property of icarResourceCollection was principally added for documentation of the intent for derived classes. The documentation could be retained in the Wiki while the definition in the JSON Schema could be removed to improve code generation.
This should not be a breaking change for ADE-1 as the member property will still be defined in all concrete collections.

@cookeac I will do this correction today and will send a PR. Also minor fix for empty inline schema which cases errors in 4.3.1 generator release.

[alamers]

I just checked @ahokkonen's pull request with Java and this version works fine for me. I generated a spring client:
java -jar ~/local/openapi-generator-cli-4.3.1.jar generate -g spring -i ~/tmp/ICAR/url-schemes/exampleUrlScheme.json
which compiles out of the box.

Not sure what I did last time; I notice that there is now an LocationsApi instead of the other API's I had. So I guess I mixed up different generators and/or versions. :( Anyway, this seems to work, and should be backwards compatible so I'll confirm the pull request.

[alamers]

@dickerpulli Can you confirm that it also works for you? Then we can close this ticket :)
Just FYI: the change is in the Develop branch, not (yet) in ADE-1.

[dickerpulli]

Hi @alamers I expected the fix to be done on branch ADE-1 so that it is fixed for version 1 also.

... currently it's only fixed on DEVELOP

[dickerpulli]

Sorry, I missed your hint, that it's only in DEVELOP :-)

I testet the DEVELOP and it works. But only with "spring" as generator language.

It also works with openapi-generator-4.3.1

[alamers]

Ok, I just tested with -g java --library resteasy and -g java --library native and those generate fine as well. Closing this ticket.