A comparison of parallelism mechanisms and common design patterns for multithreaded Android application development

Rad prvo uvodi pojam paralelizma, istodobnosti i asinkronosti te opisuje zasto su vazni za korisnicko iskustvo u Android aplikacijama i opcenito u aplikacijama s korisnickim suceljem. Zatim opisuje tri najvaznija mehanizma istodobnosti na Androidu: dretve u Javi, biblioteka RxJava i korutine u Kotlinu. Daje opis njihovog rada, nacina koristenja, cestih problema i anti-obrazaca te preporucenog nacina koristenja. Kako su korutine trenutno sluzbeno pre- poruceni mehanizam istodobnosti na Androidu, pokriva se i njihovo jedinicno testiranje. Na kraju teorijskog dijela dana je usporedba navedenih mehanizama prema kvalitativnim kriteri- jima i preporuka mehanizma u ovisnosti o aplikacijskim zahtjevima. U prakticnom dijelu je opisana, implementirana i testirana potpuna aplikacija za vremensku prognozu koja za svoje potrebe istodobnosti koristi korutine. Korutinama se izbjeglo blokiranje glavne dretve i, u slucaju uredaja s vise obradbenih jedinica, ubrzalo preslikavanje podataka za prikaz na sucelju.This thesis rst introduces the concepts of parallelism, concurrency and asynchronicity and then describes what makes them so important for user experience in Android applications and GUI applications in general. After that, it describes the three most important concurrency mechanisms on Android: Java threads, the RxJava library and Kotlin coroutines. It describes the way they work, the way they should be used, their common issues and anti-patterns and nally the recommended usage patterns. Being as coroutines are currently the ocially recom- mended concurrency mechanism on Android, their unit testing is also covered. After coroutine testing, a comparison of the three mechanisms is given based on qualitative criteria, and a recommended mechanism is given based on application requirements. A complete weather ap- plication that uses coroutines for it's concurrency needs is then described, implemented and tested. With coroutines, the main thread remained unblocked and, when running on a device with multiple processing units, the raw data was more quickly mapped to be displayed on the user interface