Java In the Undergraduate Lab

Questions about using Java in the Ugrad Lab

What machines should I be using in the undergrad lab?

If you are running a Java applet (with the appletviewer or netscape), then do NOT use any of the machines with the NCD monitors (the letters NCD are in the lower left corner). These machines have X set up incorrectly and will cause a crash if you try to run an applet.

The instructions below should set things up so that you can use any of the inon-NCD machines in 1B54 and adjoining rooms. Try to avoid using nag. If you must do a remote login, use the slogin commmand to one of the machines listed below.

HP-UX	SOLARIS	LINUX
nagtje	nago	m or em
tigger	squish	n or en
chandom	perciatelli	o or oh
taussky	fedelini	p or pee
nagina	american	q or queue
nagik	fontina	r or are
nagita	mimolette	s or ess
nagschen	colby	t or tee
nagy	ricotta	u or you
napier	mozzarella	v or vee
	swiss	w or doubleu
	cheddar	x or ecks
	edam	y or why
	gouda	z or zee
	muenster
	provolone
	brie
	bird-1 to bird-17
	csel-ultra-1 to csel-ultra-20

What do I need to change in my .cshrc file to use Java in the ugrad lab?

In your set path command, you should add these directories:

/tools/cs/top/java/bin
/tools/edu/java/bin
/tools/cs/netscape-4.07/bin

The first directory is the Java Development Kit for the HP machines and PC Linux boxes. The second directory is the JDK for the Solaris machines. The third directory has the latest Netscape 4.07 (with support for the AWT Version 1.1.5). Put the two Java directories before the Netscape directory in your path, and put the Netscape directory before the X11 directory. For example, my entire set path now looks like this (in .cshrc):

      set path= ( /usr/local/bin /usr/bin /usr/ucb /bin 
                  /tools/cs/top/java/bin /tools/edu/java/bin
                  /tools/cs/netscape-4.07/bin \
                  /usr/local/gnu/bin ~/bin \
                  /tools/edu/BinProlog /tools/cs/scheme/bin \
                  /usr/local/X11/bin . )

Once you've made this change, you can run these commands from the command line:

javac foo.java
(Compiles foo.java, resulting in foo.class.)
java foo
(Runs the Java applications foo.class.)
appletviewer foo.html
(Runs any applets in foo.html.)
netscape
    (Runs Netscape 4.07 with Java AWT 1.1 support.)
    NOTE: If you have a CLASSPATH set, then that
    must be unset before running netscape, with
    the command: unsetenv CLASSPATH.

Do I need anything special to run the appletviewer command?

Just set your path as shown in the previous answer. Then you can run a command such as

      appletviewer foo.html

The appletviewer will run any applets that are embedded in the foo.html file.

Where's the documentation for the Java Class Libraries?

I use the API Specification link in http://java.sun.com/products/jdk/1.2/docs/index.html. For example, here you will find the hashtable (java.util.Hashtable) and the Graphics class (java.awt.Graphics).

You might also want to browse all the Java code I've written in the directories:

Can I use emacs and the Java Development Environment in the ugrad lab?

Not yet. Our emacs installation is too old. I'll send you email if that situation improves. For now, go ahead and use your favorite editor to edit your java programs; then compile and run the programs from the unix command line.

On the other hand, if you're using emacs at home (on a Windows or Linux machine), then you might want to install the Java Development Environment.

Michael Main (main@colorado.edu)