Main.kt

fun main(args: Array<String>) {
    val data = StockHelper.data("src/main/kotlin/data/STOCK.json")!!
  
    // Basic example of where I would use it, creating a map of dates and changes for each day
    // I'd then probably further display this on a chart.
    val dailyChanges = data.map { it.date to it.change }
  
    // ... Displaying of chart here
  
}

Stock.json

[
  {
    "date": "2018/01/10",
    "close": 0.25,
    "volume": 500000,
    "open": 0.5,
    "high": 0.5,
    "low": 0.25
  }
]

StockHelper.kt

import com.beust.klaxon.Klaxon
import java.io.File

object StockHelper {

    data class StockEntry(
            val date: String,
            val close: Double,
            val volume: Int,
            val open: Double,
            val high: Double,
            val low: Double
    ) {
        val change: Double
            get() = close - open

        val movement: Double
            get() = high - low
    }

    fun data(loc: String): ArrayList<StockEntry>? {
        return ArrayList(Klaxon().parseArray<StockEntry>(File(loc).inputStream()))
    }

}