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()

Answer 1

I Put in the beginning of Gradle (Module app)

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'

and

implementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"

or

implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"

in the dependencies section

In the build.gradle (Project)

buildscript {
    ext.kotlin_version = '1.2.0'
    repositories {
        jcenter()
        google()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.0.1'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

Answer 2

In my case reducing version of kotlin fixed the issue

Change

ext.kotlin_version = '1.3.21'

To

ext.kotlin_version = '1.3.11'

Answer 3

For easy reference, here are the reflection dependencies when using Gradle:

Reflection libraries from the docs for Gradle in your build.gradle

dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
    compile "org.jetbrains.kotlin:kotlin-reflect"
    testCompile "org.jetbrains.kotlin:kotlin-test"
    testCompile "org.jetbrains.kotlin:kotlin-test-junit"
}

Reflection libraries syntax for Kotlin Script Gradle DSL in your build.gradle.kts

dependencies {
    compile(kotlin("stdlib"))
    compile(kotlin("reflect"))
    compile(kotlin("test"))
    compile(kotlin("test-junit"))
}

Answer 4

I used

implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"

Instead of

implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"