Kotlin Foo::class.java "Unresolved Reference: Java" error

Question

I am trying to convert my Java code of HomePage.class to Kotlin. I am following the instructions on Kotlin.org:

getClass()

To retrieve the type information from an object, we use the javaClass extension property.

val fooClass = foo.javaClass

Instead of Java’s Foo.class use Foo::class.java.

val fooClass = Foo::class.java

I have a class called HomePage that extends AppCompatActivity (in Android). I am using Android Studio. I tried doing HomePage::class.java and it has an error: Unresolved reference: java

How do I get this to work?

Answer 1

The issue is most likely that you forgot to depend on the reflection libraries which were needed for the reflective functions of Kotlin.

On the Java platform, the runtime component required for using the reflection features is distributed as a separate JAR file (kotlin-reflect.jar). This is done to reduce the required size of the runtime library for applications that do not use reflection features. If you do use reflection, please make sure that the .jar file is added to the classpath of your project.

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