Conventions Used in This Book

Italic is used for:

• New terms where they are defined

• Emphasis in body text

• Pathnames, filenames, and program names; however, if the program name is also the name of a Java class, it is written in constant width font, like other class names

• Host and domain names (e.g., http://www.maptools.org)

Constant width is used for:

• Code examples and fragments

• Anything that might appear in an XML document, including element names, tags, attribute values, entity references, and processing instructions

• Anything that might appear in a program, including keywords, operators, method names, class names, utilities, and literals

Constant width bold is used for:

• User input

• Emphasis in code examples and fragments

Constant width italic is used for:

• Replaceable elements in code statements

This icon indicates a tip, suggestion, or general note.

This trap icon indicates a warning or caution.

Case-sensitive filenames and commands don't always allow authors to adhere to standard English grammar. It is usually possible to rewrite the sentence so the two don't conflict, and when possible I have endeavored to do so. However, on rare occasions when there is simply no way around the problem, I let standard English come up the loser.

Finally, many of the examples used here are designed for you to follow along with. I hope you can use the same code examples, but for reasons beyond my control, they might not work. Please feel free to reuse them or any parts of them in your own code. No special permission is required. As far as I am concerned, they are in the public domain (though the same isn't true of the explanatory text).