Conventions

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 following are the descriptions of the properties we used in the hadoop.properties file."

A block of code is set as follows:

Path file = new Path("demo.txt");
FSDataOutputStream outStream = fs.create(file);
outStream.writeUTF("Welcome to HDFS Java API!!!");
outStream.close();

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

Job job = Job.getInstance(getConf(), "MLReceiveReplyProcessor");
job.setJarByClass(CountReceivedRepliesMapReduce.class);
job.setMapperClass(AMapper.class);
job.setReducerClass(AReducer.class);
job.setNumReduceTasks(numReduce);

job.setOutputKeyClass(Text.class);
job.setOutputValueClass(Text.class);
job.setInputFormatClass(MBoxFileInputFormat.class);
FileInputFormat.setInputPaths(job, new Path(inputPath));
FileOutputFormat.setOutputPath(job, new Path(outputPath));

int exitStatus = job.waitForCompletion(true) ? 0 : 1;

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

205.212.115.106 - - [01/Jul/1995:00:00:12 -0400] "GET /shuttle/countdown/countdown.html HTTP/1.0" 200 3985

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: "Select Custom Action in the Add Bootstrap Actions drop-down box. Click on Configure and add."