Example.kt

interface DataSource {
    fun getCachedData(): String
}

class LocalDataClient: DataSource {
    private val jsonFile = resources.getFile(JSON_FILE_TAG)
  
    override fun getCachedData() = jsonFile.toString()
}

class DataViewModel(private val dataClient: DataSource) {
    fun getCachedData() = dataClient.getCachedData()
}

// Container of objects shared across the whole project
class DependencyInjector {
    val localDataClient: DataSource = LocalDataClient()
}