The development of reactive systems is a complex task, requiring a deep understanding of the domain. A knowledge of distributed systems and asynchronous programming is required.

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We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

We also provide a PDF file that has color images of the screenshots/diagrams used in this book. You can download it here: https://www.packtpub.com/sites/default/files/downloads/9781787284951_ColorImages.pdf.

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "The first call invokes onSubscribe(), which stores Subscription locally and then notifies Publisher about their readiness to receive newsletters via the request() method."

A block of code is set as follows:

@Override
public long maxElementsFromPublisher() {
    return 1;
}

Any command-line input or output is written as follows:

./gradlew clean build

Bold: Indicates a new term, an important word, or words that you see onscreen.