Introduction To Java - MFC 158 G

Fall 2000

The Java Development Environment

Because developing Java on Windows or Unix typically requires that you be familiar with command line syntax (and the fact that some students may have not had experience in this area) this document should provide enough information to allow you to “easily” develop programs.

Installing Java From the “Java How to Program” CD (for Windows 95/98/NT):

Check to see if you have at least 200MB of space on your hard drive. You can go to “My Computer” and right click the C or D drive (then select properties)

When you get to the “where do you want to install the JDK portion” of the installation, make sure that your write down the Drive letter and full directory path of where you installed the Sun JDK 1.2 (i.e. C:\JDK1.2) We need this for a future step.

- insert the CD

- Click “My Computer”

- Click “Welcome.html”

- Scroll to near the bottom of the page and select “Install Win32Version”

- Select “Run this program from current location” and click OK

- Select yes to “Do you want to install?”

- Click next

- Click Yes

- Click next

- Click next

- After installation, reboot.

Setting up your work area (directory) and sample code from the book:

- from the MS-DOS prompt (or Command Prompt), you can select various hard drives on your system (if you have more than one) by typing the drive letter followed by a colon

o > C:

o > D:

- from the MS-DOS prompt (or Command Prompt), get to the root directory of your disk by:

o > cd \ {note a BACK-slash \ instead of Unix’s FORWARD-slash / }

o > mkdir mfc158

o > cd mfc158

o > mkdir examples (for the book samples)

o copy the examples directory contents into your hard drive examples directory. This can be done EASILY using Windows Explorer.

o You might want to create other subdirectories off of your mfc158 directory for things like homework1, homework2, etc. as opposed to simply putting all assignments in the same directory. That’s up to you!

-

The Java Development Environment

Setting up a “Dos” batch file for updating your path. This allows you to easily access the Java compiler and other Java tools. These commands could be typed in manually, but the batch file allows us to enter the commands in a file, then simply type the filename to execute all the commands.

- Make sure you’re in the mfc158 directory and start up notepad as follows:

o > notepad jdk12.bat

o We need to modify the DOS search path so that when you type “javac”, the system can find the file in the JDK install directory. The contents of the file should look something like (copy and paste if you like).

REM -------- JDK12.bat - for MFC158 ---------

REM --- Setting up the PATH so the Java commands can be found.

REM --- If you installed Java elsewhere, substitute "c:\jdk1.2\bin" with

REM --- "________\bin" where "________" is the installation location

path=%path%;c:\jdk1.2\bin

REM --- Calling the program DOSKEY so that previous commands can be recalled

REM --- Using the Uparrow/Downarrow Keys

Doskey

Note that REM is a comment command, so only 2 commands are actually being executed in this Batch file.

- save the file as jdk12.bat (or whatever other name you choose)

Testing your installation

- execute the batch file by typing the name of the file (the .bat isn’t necessary, but it will also work)

o > jdk12 (or jdk12.bat)

o > java -version (you should see something like):

java version "1.2"

Classic VM (build JDK-1.2-V, native threads)

- Now test an example program.

o > cd examples (you must of course be in the mfc158 directory)

o > cd ch02

o > cd fig02_01 (this is where the book’s example Figure 1 from Chapter 2 is (pg 36)

o > javac Welcome1.java (Case sensitivity is critical)

o You should have created a Welcome1.class file

o > java Welcome1 (recall that you don’t specify the .class file)

You should see:

Welcome to Java Programming!

- If all worked well, you are ready to start developing Java

Dos and Unix Commands Comparison Quick Reference

DOS command	Unix command	Function
Directory manipulation
cd directoryname {note \ - back slash}	cd directoryname {note / - forward slash }	Change directory – into a directory below the current
cd ..	cd ..	Change directory – up one level
cd \	cd /	Change directory to the root directory
***no equivalent***	cd ~username	Change directory to a user’s home directory
dir	ls – l (or ls)	List contents of a directory
dir | more	ls – l | more	List directory contents (page at a time)
mkdir directoryname	mkdir directoryname	Create a directory
File manipulation
copy oldfile newfile	cp oldfile newfile	Copy a file
rename oldname newname	mv oldname newname	Rename a file
move filename directory	mv filename directory	Move a file to another directory
delete filename	rm filename	Deletes a file
type filename | more	More filename	View a file contents – page at a time
Notepad filename	xemacs filename pico filename	Invoke a text editor
Command recall
doskey	No command needed	program for recalling previous commands
Up-arrow / down-arrow	Up-arrow / down-arrow	Recall previous commands that were entered
Java development commands
javac someprogram.java	javac someprogram.java	Compile a java program
java someprogram	java someprogram	Execute a java application (.class file)
appletviewer someprogram.html	appletviewer someprogram.html	Execute a java applet, through the reference of an HTML document
Miscellaneous commands
exit	exit	Exit out of environment

Getting HELP: For more information on a command, you can do the following:

DOS: command/? {Where command is a valid command like copy, type, etc.}

UNIX: man command {Where command is a valid command like ls, more, less, etc.}