Java 8 vs Project Reactor: What are the differences?

Key Differences between Java 8 and Project Reactor

In this article, we will discuss the key differences between Java 8 and Project Reactor, a popular reactive programming library for Java.

1. Asynchronous Programming: Java 8 provides CompletableFuture for implementing asynchronous programming, while Project Reactor offers Flux and Mono to achieve the same. CompletableFuture allows chaining of asynchronous operations, while Flux and Mono provide a stream-like API for reactive programming.

2. Functional Programming: Java 8 introduced lambda expressions and functional interfaces to support functional programming. Project Reactor takes this concept further by providing a rich set of functional operators and utilities for composing reactive streams.

3. Backpressure Handling: Java 8 does not provide built-in backpressure handling mechanisms for dealing with overloaded publishers. In Project Reactor, backpressure handling is an integral part of the library, allowing consumers to control the rate at which they can handle incoming data.

4. Reactive Streams Specification: Java 8 does not include a standard reactive programming API. Project Reactor, on the other hand, adheres to the Reactive Streams specification, which defines a set of interfaces, methods, and protocols for implementing reactive programming in a standardized way.

5. Error Handling: In Java 8, errors and exceptions are typically handled using try-catch blocks. Project Reactor introduces the concept of onError and onErrorResume operators to handle errors in a reactive manner. These operators allow for graceful error handling and fallback mechanisms.

6. Concurrency Models: Java 8 provides traditional multi-threading and the CompletableFuture API for concurrent programming. Project Reactor, on the other hand, is built on top of the Reactor Core library, which leverages the power of the Reactor Scheduler to provide various concurrency models, such as parallel processing, event-driven programming, and non-blocking I/O.

In Summary, Java 8 provides some support for asynchronous and functional programming, while Project Reactor takes reactive programming to the next level with its rich set of utilities, backpressure handling, adherence to the Reactive Streams specification, error handling mechanisms, and advanced concurrency models.