[Java][Client] Support primitives and arrays in oneOf

[karzang]

As described in #12556 it is not possible to use schemas with primitive types or schemas of array type since the java client generator does only support schemas of type 'object' in oneOf. This change supports the use of primitives and arrays in oneOf without the need to wrap them into objects.

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[dinuta]

Hi team, Do you need additional checks on this ?

If you can provide a snapshot I can validate also.

[wing328]

@dinuta please bulid the JAR locally to help test this PR.

git checkout -b karzang-issue_12556 master
git pull https://github.com/karzang/openapi-generator.git issue_12556
mvn clean package -DskipTests -Dmaven.javadoc.skip=true

then run you tests with modules/openapi-generator-cli/target/openapi-generator-cli.jar

[dinuta]

Hi team,

Made 1 test with the following config (to generate a client consumer):
{
...
"library": "rest-assured",
"serializationLibrary": "jackson"
...
}

The classes seems fine, but there aren't the swagger annotations on the api classes as per 6.2.1 version:
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import io.swagger.annotations.ApiResponse;
import io.swagger.annotations.ApiResponses;

Example annotations:
@ApiModelProperty(value = "The name of the files to pick up.")
@Api(value = "SomeApiProfiles")

It might not be so relevant for the issue, but I'll try to generate for okhttp3 with gson also. Don't know when I'll finish.

Any questions ? Thoughts?

[karzang]

@dinuta @wing328 Has this PR a chance of being merged soon?

[wing328]

@karzang sorry for the delay. can you please PM me via Slack https://join.slack.com/t/openapi-generator/shared_invite/zt-12jxxd7p2-XUeQM~4pzsU9x~eGLQqX2g to quickly walk through this PR?

[wing328]

FYI @OpenAPITools/generator-core-team

[wing328]

can you please merge the latest master into your branch if you've not yet done so?

this file shouldn't be generated in the latest master.

[karzang]

i rebased on top of the master but the existing samples were not deleted when calling ./bin/generate-samples.sh

I removed some samples that were falsely generated. Please let me know if you find more files which should not be generated.