isRegularFile

Checks if the file located by this path is a regular file.

inline fun Path.isRegularFile(vararg options: LinkOption): Boolean(source)

import java.nio.file.Paths

fun main() {
    val path = Paths.get("example.txt")

    if (path.isRegularFile()) {
        println("${path.fileName} is a regular file.")
    } else {
        println("${path.fileName} is not a regular file.")
    }
}

Source