Concurrent programming can be scary. Anyone who tried to use Threads and Runnable in Java,or worked with 'volatility' and 'synchronization' was most likely scarred by this experience for years to come.
Fear no more! With Kotlin, we get an access to Coroutines – fluent way of creating asynchronous flows. Fortunately, Java hasn`t stayed behind and has been improving its workflows with CompletableFuture.
In this talk, we will explore asynchronous programming in Kotlin and Java, look at its origin in JavaScript Promises, highlight how both languages moving towards declarative style of programming and allow you to choose between two solutions of Coroutines and CompletableFutures.
As a demo, we will attempt to use asynchronous programming while building a self-contained Web Crawler in a matter of minutes.