Introspectors for Kotlin

Fixture Monkey provides some additional introspectors that support the generation of Kotlin classes.

PrimaryConstructorArbitraryIntrospector #

The PrimaryConstructorArbitraryIntrospector becomes the default introspector when the Kotlin plugin is added. It creates a Kotlin class with its primary constructor.

In the case of using PrimaryConstructorArbitraryIntrospector, it only contains the properties of the Kotlin constructor parameter.

If you use your own ArbitraryIntrospector instead of PrimaryConstructorArbitraryIntrospector, it will contain the properties of the Kotlin constructor parameter, Field, Getter. So it contains the properties of the parent Field and Getter. You can customize the all properties by ArbitraryBuilder APIs.

For example, if you apply the JacksonPlugin after applying the KotlinPlugin, you can generate an instance of the Kotlin type by Jackson. In this case, you can customize the parent fields.

Example Kotlin Class :

data class Product (
  val id: Long?,

  val productName: String,

  val price: Long,

  val options: List<String>,

  val createdAt: Instant
)

Using PrimaryConstructorArbitraryIntrospector :

@Test
fun test() {
  val fixtureMonkey = FixtureMonkey.builder()
      .plugin(KotlinPlugin())
      .build()

  val product: Product = fixtureMonkey.giveMeOne()
}

KotlinAndJavaCompositeArbitraryIntrospector #

The KotlinAndJavaCompositeArbitraryIntrospector is an introspector designed to assist in the creation of Kotlin classes that reference Java classes.

Example Kotlin Class :

class KotlinClassWithJavaClass(val javaObject: JavaObject)

Example Java Class :

public class JavaObject {
    private String value;
    private Map<String, String> map;

    public JavaObject() {
    }

    public String getValue() {
        return value;
    }

    public void setValue(String value) {
        this.value = value;
    }

    public Map<String, String> getMap() {
        return map;
    }

    public void setMap(Map<String, String> map) {
        this.map = map;
    }
}

Using PrimaryConstructorArbitraryIntrospector :

    fun kotlinClassWithJavaClass() {
        // given
        val sut: FixtureMonkey = FixtureMonkey.builder()
            .plugin(KotlinPlugin())
            .objectIntrospector(KotlinAndJavaCompositeArbitraryIntrospector())
            .build()

        // when
        val actual = sut.giveMeOne<KotlinClassWithJavaClass>()

        then(actual).isNotNull
        then(actual.javaObject).isNotNull
    }

For Kotlin and Java classes respectively, it uses the PrimaryConstructorArbitraryIntrospector and the BeanArbitraryIntrospector by default.

If changes are desired, these can be injected as arguments.

    // given
    val sut: FixtureMonkey = FixtureMonkey.builder()
        .plugin(KotlinPlugin())
        .objectIntrospector(
            KotlinAndJavaCompositeArbitraryIntrospector(
                kotlinArbitraryIntrospector = PrimaryConstructorArbitraryIntrospector.INSTANCE,
                javaArbitraryIntrospector = ConstructorPropertiesArbitraryIntrospector.INSTANCE
            )
        )
        .build()