1. The book starts with an introduction and then builds on a simple service, step by step, through the chapters. Hence, the readers will benefit by following the flow of the book, unless they are looking for a particular topic.
2. Downloading the code and running it is always tempting. However, you will benefit more as you type the code out, especially in the initial chapters. The book is written in such a way that the important concepts and code are present in the chapter, thus preventing you from going back to see the source code.
3. Having said that, do try out the code samples and run them. It makes the principles concrete and easier to grasp. 
4. I hope that you have invested in a good desktop/laptop, given that you will be running containers and VMs on your machine, which take resources, it is good to have a strong piece of equipment to get going. 
5. Refer to the documentation links mentioned through the chapters to expand the knowledge on the frameworks and technologies discussed in the book.
6. The cloud is a technology that changes very rapidly. Hence, this book stresses on concepts and demonstrates them through code. For example, CQRS is important as a concept, so we have shown implementation on MongoDB and Elasticsearch. However, you can try out the pattern on any other set of databases.

You can download the example code files for this book from your account at www.packtpub.com. If you purchased this book elsewhere, you can visit www.packtpub.com/support and register to have the files emailed directly to you.

You can download the code files by following these steps:

1. Log in or register at www.packtpub.com.
2. Select the SUPPORT tab.
3. Click on Code Downloads & Errata.
4. Enter the name of the book in the Search box and follow the onscreen instructions.

Once the file is downloaded, please make sure that you unzip or extract the folder using the latest version of:

• WinRAR/7-Zip for Windows
• Zipeg/iZip/UnRarX for Mac
• 7-Zip/PeaZip for Linux

The code bundle for the book is also hosted on GitHub at https://github.com/PacktPublishing/Cloud-Native-Applications-in-Java. 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/CloudNativeApplicationsinJava_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 CrudRepository interface comes with a set of default methods to implement the most common operations."

A block of code is set as follows:

-- Adding a few initial products
insert into product(id, name, cat_Id) values (1, 'Apples', 1) 
insert into product(id, name, cat_Id) values (2, 'Oranges', 1) 
insert into product(id, name, cat_Id) values (3, 'Bananas', 1) 
insert into product(id, name, cat_Id) values (4, 'Carrot', 2) 

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

public class Product implements Serializable {

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

mongoimport --db masterdb --collection product --drop --file D:datamongoscriptsproducts.json 

Bold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "Next, we click on the Deployment credentials link on the left-hand side."