Posting answer for folks developing android applications with Kotlin; also this is the only answer that comes up in search as first main result for code performance of Kotlin in android.
A simple Kotlin answer is already present on this thread for measuring perf in ms and nanosec -
but my solution will help folks who want to log and execute function inline same time after execution completes, also is a cleaner approach when there is multiple performance measurement involved of different functions
Create functions as such:
//the inline performance measurement method
private inline fun <T> measurePerformanceInMS(
logger: (Long) -> Unit,
function: () -> T)
: T {
val startTime = System.currentTimeMillis()
val result: T = function.invoke()
val endTime = System.currentTimeMillis()
logger.invoke( endTime - startTime)
return result
}
//the logger function
fun logPerf(time: Long){
Log.d("TAG","PERFORMANCE IN MS: $time ms ")
}
//the function whose performance needs to be checked
fun longRunningFunction() : Int{
var x = 0
for (i in 1..20000) x++
return x
}
This way you can keep logging, performance computation and function execution under a single function call and no code replication needed.
If you require nano second measurement then use System.nanoTime()
USAGE :
val endResult = measurePerformanceInMS({time -> logPerf(time)}){
longRunningFunction()
}
NOTE : here the 'endResult' will carry the result of function whose performance was being measured.