Kotlin extentions to check out if all words are presented in the string

StringUtils.kt

// Usage:
// if (fullname.containsWords(searchString)) { doStuff() }

fun String.containsWords(str: String?): Boolean {
    val words = str?.trim()?.lowercase()?.split("\\s".toRegex())?.toTypedArray()
    return Arrays.stream(words).allMatch { s: CharSequence? -> this.lowercase().contains(s.toString().lowercase()!!) }
}

// Usage:
// val words = searchString.trim().split("\\s".toRegex()).toTypedArray()
// if (fullname.lowercase().containsWords(words)) { doStuff() }

fun String.containsWords(words: Array<String>?): Boolean {
    return Arrays.stream(words).allMatch { s: CharSequence? -> this.lowercase().contains(s.toString().lowercase()!!) }
}