Throughout the book, concrete programming constructs or program output are presented in a monospaced font. For example, when abstractly discussing server-side programs that use HTTP, we might refer to "HTTP servlets" or just "servlets," but when we say HttpServlet we are talking about a specific Java class.
User input is indicated in boldface, and command-line prompts are either generic ( Prompt> ) or indicate the operating system to which they apply ( DOS> ). For instance, the following indicates that " Some Output " is the result when " java SomeProgram " is executed on any platform.
Prompt> java SomeProgram Some Output
URLs, filenames, and directory names are presented in a sansserif font. So, for example, we would say "the StringTokenizer class" (monospaced because we're talking about the class name ) and "Listing such and such shows SomeFile.java " (sans-serif because we're talking about the filename). Paths use forward slashes as in URLs unless they are specific to the Windows operating system. So, for instance, we would use a forward slash when saying "look in install_dir /bin " (OS neutral) but use backslashes when saying "see C:\Windows\Temp " (Windows specific).
Important standard techniques are indicated by specially marked entries, as in the following example.
Notes and warnings are called out in a similar manner.