Kotlin Coroutine

Transcript

1. Kotlin Coroutine Bruce Kim
2. Coroutine - Cheaper than thread [Explore01Thread] - a new way of managing background threads that can simplify code by reducing the need for callbacks. - Coroutines are a Kotlin feature that convert async callbacks for long-running tasks, such as database or network access, into sequential code.
3. - Parallel Stream Structure of [functional] sequential code is the same as parallel code - Coroutine Structure of [Imperative] synchronous code is the same as asynchronous code
4. Parallel vs Asynchronous - Where we are in JVM - Node was a huge paradigm shift. And it’s real power when it comes to scale - Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient.
5. Concurrency vs Non-blocking - Want to move on without waiting
6. Let’s examine parallel just a bit, in java - Parallel Stream [test1Stream] Structure of [functional] sequential code is the same as parallel code
7. Why not be happy with that? - Sequential code and parallel code structure was so different
8. Functional style is awesome - But, handling exceptions is a mess - Coroutines are asynchronous
9. From synchronous to asynchronous - [Explore02Launch] - launch
10. Blocking to non-blocking -16ms - 16ms * 60 frames = 960 ms O - 17ms * 60 frames = 1020ms X - 60 pages per second is ideal, as most people see this as high-quality, smooth motion.
11. Blocking to non-blocking -16ms Good Bad
12. How coroutines work? - Continuation [Explore03Continuation] - Traditional web server request vs human conversation
13. A sequential code [Explore04Http]
14. Using suspend While it's suspended waiting for a result, it unblocks the thread that it's running on so other functions or coroutines can run.
15. Doing asyn - [Explore05HttpAsync] - Deferred - Kotlin has a method Deferred.await() that is used to wait for the result from a coroutine started with the async builder.
16. CallbackToCoroutine [Explore06CallbackToCoroutine] - runBlocking
17. Reference - KotlinConf 2018 - Exploring Coroutines in Kotlin by Venkat Subramariam - How to Kotlin - from the Lead Kotlin Language Designer (Google I/O '18) - Android coroutine example - Converting existing callback APIs with coroutines - Testing coroutines Code: https://github.com/realwind2048/kotlinCoroutine