ShareWare CourseWare Frequently Asked Questions

Most folks install the JRE or JSDK in a well-known place. If you are using Windows, look in the "Program Files\JavaSoft" folder. If you are using Unix/Linux, look in the "/usr/java" directory. Failing that, it's probably best to install the JRE or JSDK again.

What version of JSDK or JRE should I install?

The CourseWare Viewer requires a JSDK or JRE version of at least 1.2. The Viewer has been extensively tested with versions 1.3 and 1.4. If you are using Linux, you will get best results using version 1.4 -- fonts will look better and copying code listings to the clipboard will work more reliably.

Which JSDK should I install, the "plain" JSDK or the "Forte" version?

Please download and install the "plain" version.

Will the Microsoft Virtual Machine work for the CourseWare Viewer?

No, the Microsoft VM is a version 1.1.x virtual machine, and the CourseWare Viewer requires a Java 2 virtual machine.

How can I tell if I already have installed Java WebStart?

If you are running Windows, look on your Start Menu. If you are running Unix/Linux, search for the javaws shell script.

I dual-boot Windows and Linux. Is there any way to take a course that works under both operating systems?

The Viewer should work fine that way (in fact, that's one of the ways we tested it!). To get it setup, take a look at the "Manual Install" method at Viewer Page

How do I start the CourseWare Viewer?

It depends on how you installed the Viewer. See the Viewer Page for details, but here are a couple of quick hints. If you are using Windows, look on the Start Menu for the "Descriptor Systems" group. If you are using Linux, look in your home directory for the "runViewer" link.

How do I start taking a course once I've installed the CourseWare Viewer and downloaded a course?

First, start the Viewer. Then use the File - Open menu to open the .crs file for the course that you downloaded (e.g. servlet.crs). If you cannot remember where you downloaded the course, use the "My Computer" search function under Windows to search for *.crs files. Under Linux/Unix, use your window manager's search facility or the find command to locate the .crs file.

Windows Questions

How can I unzip a file?

There are numerous unzip utilities that work in Windows. Perhaps the most popular is WinZip. You can download a free evaluation version from their web site. There's also a free, Java-based zip utility called ZipAnywhere that works well. You can download it from http://www.geocities.com/zipanywhere

Linux/Unix Questions

How do I unpack a "tar.gz" file?

You can use the "gzip" and "tar" utilities. Open a console and change to the directory where the "xxx.tar.gz" file is located. Then enter:

      gzip xxx.tar.gz
      tar xvf xxx.tar

You should see the unpacked files in the directory.

Some of the graphics look messed up. Especially some of the text seems too long.

There are significant differences between how fonts work in Linux and Windows even though Java is Write Once, Run Everywhere. One problem is that there are no exact font matches between platforms. We have tried to design the graphics so they look OK under both Linux and Windows, but if you see some that are messed up, please drop Support us a line.

I have the "viewer.sh" file in my directory, but I cannot execute it!

Make sure the file has the executable flag set:

      chmod +X viewer.sh

And to run a file out of the current directory, use a command like:

       ./viewer.sh

Miscellaneous Questions

Is there any way to get a hard copy of the labs?

Yes, but to get hard copies of all the labs, you will need to license your course. Once you license the course, you will be able to download Adobe PDF files for the lab documentation which you can then print. Note that we provide the PDF for the first lab free of charge. Look in the directory where you installed the course, e.g. the "/servclass" directory for the Servlet Programming course.

Is there any way to copy and paste code listings from the Courseware Viewer?

Yes. Just click the right mouse button on the code listing and choose the "Copy to Clipboard" popup menu. Note that copying to the clipboard does not work reliably under Linux unless you are using Java version 1.4 or later.

How do I license a course?

First you must obtain a registration code from Licensing. Then, from the Viewer's Help - License menu, enter your registration code.

Why should I pay to license a course?

Everyone has a different way of learning, but for many people, the best learning comes from doing. That's why we have spent so much time and effort writing effective lab exercises. And to use our labs, you'll need to license the course! ;-) In addition, once you license the course, you will be able to download PDF files for the lab exercise documentation so you can print them out. Many people find working from a print-out more convenient than reading the lab documentation on the computer.

Is there a way to notify Descriptor Systems about typos and bugs?

Absolutely! We would very much appreciate it. Please contact Support.

Can I take a ShareWare CourseWare course if my computer's not running Windows or Linux?

The CourseWare Viewer is a Java program, and thus should work on any platform where there's a viable Java2 Runtime Environment. However, we have only tested the Viewer on Windows and Linux. If you have success running the Viewer on another platform, please email us with your hints and tips so we can update this FAQ.

I successfully licensed a course and it worked fine. But now I cannot view the lab exercises anymore.

If you changed something on your hard disk, the CourseWare Viewer perhaps cannot find your registration code. To fix that, simply find the email containing your registration code (you did save the email, didn't you?) and re-enter the registration code in the CourseWare Viewer's Help - License menu. If that doesn't work, contact Support.

Can I add a question to the FAQ?

Absolutely! We would very much appreciate it. Please contact Support.

Why does Java Web Start show that nasty message saying that the Courseware Viewer is asking for "full access" to my computer?

So that folks will trust programs downloaded via Java Web Start, Sun has provided a technique so that developers can apply a digital certificate to their programs. The digital certificate verifies that the program actually came from the developer and that the program has not been tampered with or modified. If a developer does not perform the steps to apply a digital certificate, you should not allow that program to access your computer!

But be assured that Descriptor Systems has followed the correct procedure using a digital certificate from Thawte, so you can be sure that the program will do your system no harm.