Use the Command Line
The command line looks something like this on my computer. Yours may use
different colors and fonts, and you can usually set these to your liking. I
apparently prefer black letters on a tan background:
You access the command line a little differently depending on the kind of
operating system you're running, which will be one of these:
Windows comes with a very bare-bones command line. You get to it by running
cmd.exe . If your version of Windows has a “Start” command, then you might
be able to select Start -> Run and enter cmd.exe or just use the search box
that comes up to find and run cmd.exe . But I don't recommend using cmd.exe
by itself; see the instructions in the box on page 4 .
On Mac OS X, open the command line via Applications -> Utilities -> Terminal.
If you're running Linux, you likely already know how to get to a command-line
shell. But for the sake of completeness, and because it's called different things,
try any of these: open a shell, start a Konsole, or right-click on the Desktop to
open a Terminal.
(Fortunately, all of these pesky differences between Windows, Mac, and Linux
disappear once you're writing Java code: Java runs the same on each platform.)
Once you have your command-line application up and running, you're ready
to type commands into the command-line processor, or shell , as I'll call it.
You'll be using a few simple commands that I'll show you as we go along.
Each shell prints out a short message indicating it's ready for you to type
something in. But instead of a straightforward prompt like “Ready for you to
type, master,” most command prompts are a little more cryptic.
Windows will show something like C:\> . Linux and Mac systems might show
$ or % . Any of these prompts might include additional information, like your
name, the computer's name, or a directory name. Since that will be different
for everyone, I'm going to choose the simplest one for the examples in this
topic and show the command prompt as a $ . Whatever your prompt looks
like, that's where you type in commands.