Upgrading from 3.1.5 to 3.1.8 (without changing annotations in any way) results in addition of some java core classes to the models section

[stoyo]

Bump of swagger-maven-plugin from 3.1.5 to 3.1.8 is not backward compatible.

All annotations in my web service look like this:

@POST
@Path("/")
@Produces({ PRODUCES_JSON_1, PRODUCES_JSON_2 })
@ApiOperation(nickname = "createFoo",
        value = "Create foo",
        notes = "Create foo",
        response = FooTracker.class,
        code = 202)
@ApiResponses(
        value = {
                @ApiResponse(code = 400, message = "Invalid Request - bad data"),
                @ApiResponse(code = 403, message = "Forbidden")
        })
@ApiImplicitParams({
        @ApiImplicitParam(name = Constants.Versions.VERSION_PARAM,
            value = Constants.Documentation.API_VERSION_PARAM_DESCRIPTION,
            dataType = "string",
            paramType = "query")
        })
@SupportedSince(Constants.Versions.TANGO_IA_VERSION)

None of the provided response classes (i.g. FooTracker in the example above) include in any way CompletableFuture or Thread class, however, in swagger models section, after bump, I started seeing:

CompletableFutureObject
CompletableFutureOperation
CompletableFuture
Thread
ThreadGroup
etc...

<plugin>
    <groupId>com.github.kongchen</groupId>
    <artifactId>swagger-maven-plugin</artifactId>
    <version>3.1.8</version>
    <configuration>
        <apiSources>
            <apiSource>
                <springmvc>false</springmvc>
                <schemes>https</schemes>
                <locations>org.fmi.service.multicloud</locations>
                <schemes>https</schemes>
                <host></host>
                <basePath>/</basePath>
                <info>
                    <title>FMI API</title>
                    <version>06-2020</version>
                </info>
                <swaggerDirectory>${project.build.outputDirectory}</swaggerDirectory>
                <swaggerFileName>swagger-multicloud</swaggerFileName>
                <templatePath>${basedir}/src/main/resources/templates/strapdown.html.hbs</templatePath>
                <outputPath>${project.build.directory}/swagger/FMI-API.html</outputPath>
                <outputFormats>json,yaml</outputFormats>
            </apiSource>
        </apiSources>
    </configuration>
    <executions>
        <execution>
            <phase>process-classes</phase>
            <goals>
                <goal>generate</goal>
            </goals>
        </execution>
    </executions>
</plugin>

I saw that this issue: #782 mentions the exact same problem, however, it has been closed without any explanation or comment from anyone.

[gdimitrov7]

The issue is with classes that have extra methods (in same or in parent class), that will be excluded from the swagger - because they do not have @Path, @Api nor @PostMapping. Even if they are ignored from the operations, their model is added to the definitions.

In the next example the produced swagger contains #/definitions/SQLException even if it is not used from the operations or from other definition:

    // this static method and return type should not be included in the swagger as there is no Path nor Api
    public static SQLException getCauseSQLException(Throwable e) {
        return null;
    }

The change happened between 3.1.5 and 3.1.6 as part of some fix for JAX-RS. Previously the extra definitions were not included in the resulting swagger.

I prepared a fix that returns the previously behaviour - hope it gets merged soon as it prevents upgrading to newer version of swagger-maven-plugin in our project.