So what is an applet? An applet is a type of computer program specifically designed to be used on a web page (A computer program is a group of instructions to tell the computer what to do). The reason for applets is that there are some things that can't be done with html. For example, making something move, counters, guestbooks, or changing pictures. There are many applets available on the web that are free for you to put on your own web pages. This section will explain how to download, install, and customize a few applets. Though every applet is a little different, this should help you if you find an applet elsewhere that you would like on your page.
Applets are almost always written in Java. We will not, however, be teaching you Java in this course as it is well beyond the scope of the course (we suggest CGS2414 for non-majors interested in Java, CIS3020 for majors).
All of the applets we will be discussing are what is called "pre-compiled". Compiling is done to convert instructions in our applet that are written in a human readable language like english to a format that the computer can understand. As a result we do not know what instructions were used and how the applets work. You can use the applet, but there are limited things you can change since you don't have the actual human readable code (instructions). This is normal for applets.
Applets are stored in files called source files. The main source file or files for an applet written in java will have an extension of "java" (for example photoalbum.java - human readable). The pre-compiled version of the same java files will have an extension of "class" (for example photoalbum.class - machine readable). Again, all of the applets we are using have an extension of class because they are pre-compiled.
The Eatme applet makes text appear as being eaten away on your webpage. The other 2 applets do things with pictures. The applets can only use gif and jpg type files, no bmp or art files. Also, they have problems using animated gifs (so don't use them). It is a good idea to use small pictures for these applets.
Here are the demos.
After you have decided on an applet to put on your page follow our DownLoading and Installation, and finally do the customizations (found on the same page).
Java Boutique has a
collection of some free applets if you want to look around there. You can also search
for them fairly easily with most search
engines (we suggest using key words applet, download,
and free).