Remove JDK7 support from Java Spring generators

[wing328]

Remove JDK7 support from Java Spring generators (default to JDK8+ starting in v6.0.0)

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cc @bbdouglas (2017/07) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01) @karismann (2019/03) @Zomzog (2019/04) @lwlee2608 (2019/10)

[cachescrubber]

Some unit tests have to be adjusted.

[wing328]

Yup, will fix those after merging your (and other) spring-related PRs.

[cachescrubber]

@wing328 Nor sure wether we should remove the implementation in apiController.mustache. Could make migration for spring-mvc users more straight forward - and could be a value for itself. WDYT?

[wing328]

Added back via 63a469f

Agreed with the direction to make the migration easier for spring-mvc users.

[cachescrubber]

Thx. I'll give more feedback and review throughout the day.

[wing328]

The code won't compile as it's missing those JDK7 import. Shall we add those import back to the controller?

Error:    symbol:   class User
Error:    location: class org.openapitools.api.UserApiController
Error:  /home/runner/work/openapi-generator/openapi-generator/samples/server/petstore/springboot/src/main/java/org/openapitools/api/UserApiController.java:[156,12] cannot find symbol
Error:    symbol:   class ResponseEntity
Error:    location: class org.openapitools.api.UserApiController
Error:  /home/runner/work/openapi-generator/openapi-generator/samples/server/petstore/springboot/src/main/java/org/openapitools/api/FakeApiController.java:[36,80] cannot find symbol
Error:    symbol:   class XmlItem
Error:    location: class org.openapitools.api.FakeApiController
Error:  /home/runner/work/openapi-generator/openapi-generator/samples/server/petstore/springboot/src/main/java/org/openapitools/api/FakeApiController.java:[35,12] cannot find symbol
Error:    symbol:   class ResponseEntity
Error:    location: class org.openapitools.api.FakeApiController
Error:  /home/runner/work/openapi-generator/openapi-generator/samples/server/petstore/springboot/src/main/java/org/openapitools/api/FakeApiController.java:[50,12] cannot find symbol
Error:    symbol:   class ResponseEntity
Error:    location: class org.openapitools.api.FakeApiController
Error:  /home/runner/work/openapi-generator/openapi-generator/samples/server/petstore/springboot/src/main/java/org/openapitools/api/FakeApiController.java:[66,97] cannot find symbol
Error:    symbol:   class OuterComposite
Error:    location: class org.openapitools.api.FakeApiController
Error:  /home/runner/work/openapi-generator/openapi-generator/samples/server/petstore/springboot/src/main/java/org/openapitools/api/FakeApiController.java:[65,12] cannot find symbol
Error:    symbol:   class ResponseEntity
Error:    location: class org.openapitools.api.FakeApiController
Error:  /home/runner/work/openapi-generator/openapi-generator/samples/server/petstore/springboot/src/main/java/org/openapitools/api/FakeApiController.java:[65,27] cannot find symbol
Error:    symbol:   class OuterComposite
Error:    location: class org.openapitools.api.FakeApiController
Error:  /home/runner/work/openapi-generator/openapi-generator/samples/server/petstore/springboot/src/main/java/org/openapitools/api/FakeApiController.java:[90,94] cannot find symbol
Error:    symbol:   class BigDecimal
Error:    location: class org.openapitools.api.FakeApiController
Error:  /home/runner/work/openapi-generator/openapi-generator/samples/server/petstore/springboot/src/main/java/org/openapitools/api/FakeApiController.java:[89,12] cannot find symbol
Error:    symbol:   class ResponseEntity
Error:    location: class org.openapitools.api.FakeApiController
Error:  /home/runner/work/openapi-generator/openapi-generator/samples/server/petstore/springboot/src/main/java/org/openapitools/api/FakeApiController.java:[89,27] cannot find symbol
Error:    symbol:   class BigDecimal
Error:    location: class org.openapitools.api.FakeApiController
Error:  /home/runner/work/openapi-generator/openapi-generator/samples/server/petstore/springboot/src/main/java/org/openapitools/api/FakeApiController.java:[104,12] cannot find symbol

Ref: https://github.com/OpenAPITools/openapi-generator/runs/5179391345?check_suite_focus=true

[cachescrubber]

Hmm, the missing imports are not jdk8 related IMO. They miss swagger.v3 and spring-web imports.

We 'll need a flag to enable usage of the "impl-in-controller" pattern? Probably the switch has been implicit via the java8 toggle.

[wing328]

Hmm, the missing imports are not jdk8 related IMO. They miss swagger.v3 and spring-web imports.

I'll try to add those import

We 'll need a flag to enable usage of the "impl-in-controller" pattern?

I suggest we go without the flag to start with. If later there's a demand for it, we can always add one.

[wing328]

Done. CircleCI failure not related to this change.

[cachescrubber]

I suggest we go without the flag to start with. If later there's a demand for it, we can always add one.

I think we still need to hide the code behind a flag. We should just not expose it via cli to make no commitment. As it is right now there is a code duplication between Api and Controller. Thanks for your patience anyway. Otherwise the PR looks good.

The code was previously hidden behind the {{^jdk8}} test. You replaced it with {{^reactive}} which is not sufficient.

[wing328]

OK. Let's go with what we've for now as I don't want to include too many changes in this PR. We can always add the option later.