Mastering High Performance with Kotlin

Concurrency and parallelism

You should use special approaches to deal with multithreading, such as RxJava or coroutines. Using RxJava, you can easily process asynchronous events in several threads:

fun singleBake(): Single<Cake> {    return Single.fromCallable { bake() }.subscribeOn(Schedulers.computation())}fun reactiveOrder(amountOfCakes: Int): Single<List<Cake>> {    val baker = Baker()    return Observable.range(0, amountOfCakes)            .flatMapSingle { baker.singleBake() }            .toList()}.....................Bakery().reactiveOrder(10) .subscribe { cakes -> println("Number of cakes: ${cakes.size}")}

Use common patterns to synchronize the work of several threads:

val lock = Lock()Bakery().reactiveOrder(10)        .doAfterTerminate { lock.unlock() }        .subscribe {  ...