7. @aalmiray
SYNC VS ASYNC
Synchronous operations block the flow until they yield a
result (success or error).
Asynchronous operations DO NOT block the flow, rather they
allow the program to continue. Results (or errors) will be
handled at a later point in time, typically using functions
(callbacks).
8. @aalmiray
FUTURES AND PROMISES
They describe an object that acts as mediator for a value that
may be unknown at init time.
The terms Future and Promise are normally used
interchangeably but thereâs a difference:
âą A Future is a read-only reference of the expected value.
âą A Promise is a write-once container that sets the value of
the Future.
https://en.wikipedia.org/wiki/Futures_and_promises
9. @aalmiray
FUTURES AND PROMISES
Futures in Java are synchronous, this can be demonstrated
by the following method signatures found in
java.util.concurrent.Future
V get()
V get(long timeout, TimeUnit unit)
10. @aalmiray
FUTURES AND PROMISES
Java 8 added a new type, CompletableFuture, that
implements CompletableStage, which in turns defines the
contract of a Promise, such as
thenAccept(Consumer<? Super T> action)
whenComplete(BiConsumer<? super T,? super Throwable>
action)
exceptionally(Function<Throwable,? extends T> fn)
⊠and many others
11. @aalmiray
FUTURES AND PROMISES
JDeferred offers a different API that allows better function
composition
Promise<D, F, P> then(DoneCallback<D> doneCallback)
Promise<D, F, P> done(DoneCallback<D> callback)
Promise<D, F, P> fail(FailCallback<F> callback)
Promise<D, F, P> always(AlwaysCallback<D, F> callback)
13. @aalmiray
DATA STREAMS
A sequence of values calculated over time.
Values are emitted when ready; they are computed without
blocking consumers.
Consumers listen to changes in the data stream and react to
said changes (hence the name Reactive Programming).
Push vs pull model.
14. @aalmiray
OBSERVABLE/OBSERVER
Data streams are of type Observable while consumer are of
type Observer.
The Observable type exposes multiple operations that allow
value composition, combinations, filtering, and other value
transformations.
NOTE: many operations from RxJava/Reactor generate a new
Observable (decorator pattern)
22. @aalmiray
HTTPS://GRPC.IO/
gRPC is a modern, open source, high-performance remote
procedure call (RPC) framework that can run anywhere. It
enables client and server applications to communicate
transparently, and makes it easier to build connected
systems.
