How to use getHour() to get current hour in kotlin - kotlin

Question

fun getHours() = int
val openHours = 7
val now = getHours()
val office: String
office = if (now > 7){
"Office already open"
} else if(now == openHours){
"wait a minute, office will be open"
}else{
"office is closed"
}
println(office)
The following code doesn't seem to get me the current hour from my computer, what am I missing?

Answer 1

The right syntax of defining a function in Kotlin would be:
// function without params and returns Unit
fun functionName1() {}
// function with one parameter and returns Int
fun functionName2(text: String): Int {
return 6
}
// short syntax for one line function with two params and Boolean as return value
fun functionName3(text: String, isVisible: Boolean): Boolean = text.isEmpty && isVisible
Code provided by you has incorrect syntax, please fix it. It should be something like this:
fun getHours(): String {
val openHours = 7
val now = getCurrentHour()
val office = when {
now > 7 -> "Office already open"
now == openHours -> "wait a minute, office will be open"
else -> "office is closed"
}
println(office)
return office
}
fun getCurrentHour(): Int {
// somehow get current hour, for example using java.util.Calendar class
return Calendar.getInstance().get(Calendar.HOUR_OF_DAY)
}

Answer 2

You can get the current system time using LocalDateTime class like :
import java.time.LocalDateTime
val currentDateTime = LocalDateTime.now()
And to get hours specifically you could use DateTimeFormatter class like:
import java.time.format.DateTimeFormatter
currentDateTime.format(DateTimeFormatter.ofPattern("HH"))

Answer 3

Basically, the answer given by #Sergey is correct.
Just one minor nit:
I would not use java.util.Date for it but one of the classes from java.time, see this example:
fun getHours(): String {
val openHours = 7
val now = java.time.ZonedDateTime.now(java.time.ZoneId.systemDefault()).hour
val office = when {
now > 7 -> "Office already open"
now == openHours -> "wait a minute, office will be open"
else -> "office is closed"
}
return office
}
using that in a fun main() like
fun main() {
println(getHours())
}
would then result in the (system dependent) output
office is closed
on my system at 08:48 o'clock in UTC+2.