In this book, you will find a number of styles of text 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 first of these additions takes care of declaring the topic exchange in the existing onApplicationStart method."

A block of code is set as follows:

rabbitMqManager.call(new ChannelCallable<DeclareOk>()
{
    @Override
    public String getDescription()
    {
        return "Declaring topic exchange: " + USER_TOPICS_EXCHANGE;
    }

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

    try
    {
        connection = factory.newConnection();
        connection.addShutdownListener(this);
        LOGGER.info("Connected to " + factory.getHost() + ":" + factory.getPort());
    }

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

$ sudo service rabbitmq-server restart

New terms and important words are shown in bold. Words that you see on the screen, in menus or dialog boxes for example, appear in the text like this: "When connected to the management console, click on the Exchanges tab."