Conventions

In this book, you will find a number of text styles that distinguish between different kinds of information. Here are some examples of these styles and an explanation of their meaning. Code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input and Twitter handles are shown as follows: "The buffer() operator accepts arguments of type integer where developers can specify how many items to bundle together."

A block of code is set as follows:

    public class Demo_flatMap { 
       public static void main(String[] args) { 
         Observable.range(1,5).flatMap(item->Observable.range(item, 
           3)).subscribe(value->System.out.print(value+"->")); 
       } 
    } 

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

got:-12
got:-30  

New terms and important words are shown in bold. Words that you see on the screen, for example, in menus or dialog boxes, appear in the text like this: "Many times, we click on the link to access very important information and suddenly we get a page saying No resource available or Service temporarily down."