Simple HTTP request using standard library

SimpleHttpRequest.kt

import com.squareup.moshi.Moshi
import com.squareup.moshi.kotlin.reflect.KotlinJsonAdapterFactory
import java.io.BufferedReader
import java.io.InputStreamReader
import java.lang.StringBuilder
import java.net.HttpURLConnection
import java.net.URL

private fun simpleHttpRequest(): JokeResponse? {
    val responseString = StringBuilder()

    val url = URL("https://icanhazdadjoke.com/")
    val conn = (url.openConnection() as HttpURLConnection).apply {
        requestMethod = "GET"
        addRequestProperty("Accept", "application/json")
    }

    BufferedReader(InputStreamReader(conn.inputStream))
        .readLine()
        .forEach {
            responseString.append(it)
        }

    val jsonAdapter = Moshi.Builder()
        .addLast(KotlinJsonAdapterFactory())
        .build()
        .adapter(JokeResponse::class.java)

    return jsonAdapter.fromJson(responseString.toString())
}

data class JokeResponse(val id: String, val joke: String, val status: Int)