Library does not support ! in GraphQL schema during the java classes generation

Describe the bug During the java classes generation, all of the fields are nullable fields

To Reproduce Steps to reproduce the behavior: Run ./gradlew graphqlCodegen Check the generated classes. Fields have no difference between nullable and not nullable.

Expected behavior Nullable fields should be assigned null Not nullable fields should be the same as of now.

[kobylynskyi]

Done in 1.2.1

[PavelSusloparov]

Actually, I did it wrong. With validator here, I have the thing working.

fun testObject(): TestObject {
        val testObject = TestObject()
        val factory = Validation.buildDefaultValidatorFactory()
        val validator = factory.getValidator()
        val violations = validator.validate<TestObject>(testObject)
        val violationsString = violations.joinToString(", ")
        if (violationsString.isNotBlank()) {
            throw Exception(violationsString)
        }
        return testObject
    }

Thanks to https://www.baeldung.com/javax-validation

@kobylynskyi , yes I believe that is the good approach to go with.