In order to get the most out of this book, some knowledge of Java and the ability to run Java programs is required. Also, it helps to have your favorite editor or, even better, an IDE installed and configured for use in the recipes. Because the book is essentially a collection of recipes, with each recipe being based on specific examples, the benefits of the book will be lost if the reader does not execute the examples provided. Readers will get even more from this book if they reproduce every example that is provided in their IDE, execute it, and compare their result with the one shown in the book.

You can download the example code files for this book from your account at www.packt.com. If you purchased this book elsewhere, you can visit www.packt.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.packt.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/Java-11-Cookbook-Second-Edition. We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

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: "Use the allProcesses() method on the ProcessHandle interface to get a stream of the currently active processes"

A block of code is set as follows:

public class Thing {
  private int someInt;
  public Thing(int i) { this.someInt = i; }
  public int getSomeInt() { return someInt; }
  public String getSomeStr() { 
    return Integer.toString(someInt); }
} 

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

Object[] os = Stream.of(1,2,3).toArray();
 Arrays.stream(os).forEach(System.out::print);
 System.out.println();
 String[] sts = Stream.of(1,2,3)
                      .map(i -> i.toString())
                      .toArray(String[]::new);
 Arrays.stream(sts).forEach(System.out::print);

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

jshell> ZoneId.getAvailableZoneIds().stream().count()
$16 ==> 599

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: "Right-click on My Computer and then click on Properties. You will see
your system information."