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 (such as database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles) are shown as follows where the code word is "10011": "This result tells the driver to drive toward the zip code 10011."

A block of code is set as follows:

PubSubWebSocketAppDataResult wsResult = dag.addOperator("QueryResult", new PubSubWebSocketAppDataResult());
  wsResult.setTopic("nyctaxi.result");
  try {
    wsResult.setUri(new URI("ws://localhost:8890/pubsub"));
  } catch (URISyntaxException ex) {
    throw Throwables.propagate(ex);
  }
dag.addStream("server_to_query_output", dataServer.queryResult, wsResult.input);

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

bash> apex 
apex> launch target/malhar-examples-nyc-taxi-3.8.0-SNAPSHOT.apa

New terms and important words are shown in bold.

Warnings or important notes appear like this.

Tips and tricks appear like this.