Is reactive programming java's way of asynchrous programming?

[Monica Shiralkar]

I am trying to understand reactive programming in Java. Is reactive programming java's way of asynchronous programming? Thanks

[Campbell Ritchie]

Monica Shiralkar wrote:. . . Is reactive programming java's way of asynchronous programming? Thanks

No. You can do asynchronous programming with ordinary multi‑threading.

Not a “beginning” question: moving you to a more appropriate forum.

[Stephan van Hulst]

Be careful, asynchronous doesn't imply concurrent.

Asynchronous programming is a style that it is characterized by passing callbacks to higher order functions. The callback may be called directly or at a later time. It may be called by the same thread or by a different one.

Concurrent programming usually requires an asynchronous style. But there are examples of asynchronous code that have nothing to do with concurrency: executing a sequential Stream is such an example.

I believe reactive programming also heavily depends on asynchronous programming, but it has a specific purpose: it's a way of handling push-based data streams by reacting to data as it enters the application. This can happen in a completely sequential manner, so concurrent threads may not be necessary. Asynchronous programming is still a useful way of reacting to events in such a way.

So no, reactive programming doesn't bring asynchronous programming to Java. It's asynchronous programming that's already available in Java that allows for reactive programming.

[Monica Shiralkar]

Stephan van Hulst wrote:
reactive programming doesn't bring asynchronous programming to Java. It's asynchronous programming that's already available in Java that allows for reactive programming.

Thanks