Troubleshooting
1) I can't view the applet from my browser window
When testing the applet, the web browser may display a blank gray box instead of the applet itself. Some web browsers like Netscape Navigator 4.01 have problems displaying Java applets that reside on the local hard disk due to Java security implementations. You may get a message like "applet JTree.class can't start: java.lang.NullPointerException". The best way to get around this is to test your applet on-line. Or you could use other browsers like Netscape Navigator 3.0 or Microsoft Internet Explorer 3.x.
The NullPointerException message could also be due to invalid parameter values. For example, the node parameters require exactly 7 fields to be entered (each delimited by the "^" symbol). Entering one less or more field could cause such an error. You should also check that all the parameter tags have been included. Missing one parameter could generate this message.
2) The bullet images looks distorted
You may notice that the bullet image of the nodes in the tree changes size with the nodes. The larger the font size, the larger the bullets will appear. The images are scaled to fit into the node so there may be some distortion as a result. Try changing the bulletSize parameter, which controls the ratio of the bullet size to to that of the node.
3) The applet doesn't start and I get a message in the Java console that says "Copyright parameter not found! Applet terminated."
For copyright reasons, I have made it a requirement to include a copyright parameter which the applet cannot run without. So whether you are trying out the applet or have registered it, you still need to include this parameter in your HTML code. Of course, for registered users, there will be no copyright message in the applet window itself.
4) When I try to load a URL in the applet's frame by clicking one of the nodes, the document loads in the other frames as well.
If you want to load something in the applet frame itself, you should set the node's target frame parameter to "_self". Avoid using the actual name of the applet frame itself.
5) The mouseOver border appear smaller than the node caption
This problem appears only in Netscape 3 and older versions due to the older java implementation. It does appear in Netscape 4.x or any MSIE above version 3.
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