Reactive Programming: What is it And Why We Need It

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Reactive Programming
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Reactive Programming is a paradigm that helps developers write event-driven applications by using observable streams of data. It’s often used in modern applications, especially on mobile devices and the web. In this article, we’ll explain what is and why we need it. We’ll also look at some of its benefits. And limitations so you can decide if it’s right for your project or not!

It is a style of software development. Used to aims to make it easier to write code that reacts to changes in data.

In this article, we will look at what reactive programming is and why it has become so popular. We’ll also look at some of the benefits and limitations of reactive programming.

How does Reactive Programming work?

Reactive Programming is a paradigm shift from the current programming model. It’s a response to the demands of modern-day software development. Systems have become more complex and require greater flexibility in order to evolve with changing requirements.

Reactive Programming is based on the concept of events, which are triggered by data changes or user interactions. These events are processed by event handlers which can send out new messages asynchronously without blocking other parts of your application code while waiting for responses from those handlers (i.e., they’re “reactive”).

Reactive Programming vs Reactive Streams

The first one is a superset of reactive streams. Reactive streams are standard for asynchronous data streams, which means they’re a way of ensuring that the processing of your code doesn’t get stuck waiting for slow data sources like HTTP requests or database queries to complete.

When we talk about “reactive” in this article, we’re referring specifically to Reactive Programming–a paradigm that makes it easier for developers and programmers alike to write code that reacts appropriately when something changes or happens unexpectedly (for example, when an error occurs).

Reactive Programming isn’t just about reacting: it’s also about being responsive and resilient in response to external stimuli (like user input).

Observable and Observers

In this programming, an Observable is a data source and an Observer is the consumer of the data. The Observable emits items to its Observers which can be added and removed dynamically during runtime. Each Observer can subscribe to one or more Observables, so there can be multiple Observers subscribed to each observable. This allows us to easily create asynchronous event buses in our applications by having multiple listeners that react when something happens on the bus (like an event).

The number of observers can go up and down during the lifetime of an observable object – this means you don’t have to worry about synchronizing threads or cleaning up resources because everything will happen automatically when needed!


Schedulers are used to execute tasks in a specific order. They’re also used to execute tasks on a specific thread, in the background, asynchronously, and more.

Schedulers have several uses:

  • Execute tasks sequentially or parallel (depending on your requirements)
  • Run tasks based on schedules (e.g., every minute)
  • Timeout for executing long-running operations

Responsive, Resilient, and Elastic

Reactive programming is responsive, resilient, and elastic.

  • Responsive: Reactive programming is responsive in the sense that it responds to changes in the environment. It can handle multiple requests concurrently and gracefully degrade when there are too many requests being made at once. This makes it ideal for writing code that will work well on mobile devices. Or used on a web server with thousands of concurrent users accessing your website at once!
  • Resilient: You should expect errors from time to time but with reactive programming, you won’t have to worry about whether or not your application will crash because of one error – it’ll just keep chugging along until another error happens (or until all errors are resolved). This means that even if something goes wrong during execution, we don’t have to worry about our code crashing completely because each operation runs independently from one another which makes debugging easier than ever before!

Benefits of Reactive Programming

It is a programming paradigm that is based on the concept of data streams. It has many benefits, including:

  • Reactive Programming can be used in a wide variety of systems and applications, including real-time systems, asynchronous systems, event-driven systems, and more.
  • It’s fast and efficient because it uses asynchronous processing techniques to minimize latency (the time between when an event happens and when your program responds).

Limitations of Reactive Programming

Reactive programming is not a silver bullet. It’s not a replacement for imperative programming, nor does it support stateful operations. In fact, reactive programming is just one part of the solution to building highly responsive applications that can handle millions of users on low-power devices and still perform well in real-time.

It’s not even really new–it simply uses some concepts from functional programming and applies them in an interesting way to make your code more readable and maintainable than ever before!

Is Reactive Programming the future?

Reactive Programming is not the future. It’s here and now.

Reactive Programming is a paradigm that allows you to write code that is more predictable, more responsive, more resilient, and elastic. It solves problems that have plagued developers for decades by introducing concepts such as asynchronous data streams (think RxJava), functional programming (think Kotlin), and domain-driven design (think Spring Boot).


This is a powerful tool that has the potential to change how we build software. But it’s not just about making things faster or more accessible, it’s about building better software that is more responsive, resilient, and elastic.

For More Info you can refer to our Blogs and official site:
1) Basic Concepts of Reactive Programming.
2) Reactive Programming With SpringBoot3.