Question

Currently, the only information I have is a one-line error message in the browser’s status-bar.

Do you know how I could get a stack-trace for example ?

Answer 1

This article is a bit old but is still relevant (including a section entitled “How to Debug Applets in Java Plug-in”).

Edit: perhaps a better way to get stacktraces is to use the Java plugin console. If you hit “t” in that window, you’ll see the following:

Prints out all the existing thread
groups. The first group shown is Group
main. ac stands for active count; it
is the total number of active threads
in a thread group and its child thread
groups. agc stands for active group
count; it is the number of active
child thread groups of a thread group.
pri stands for priority; it is the
priority of a thread group. Following
Group main, other thread groups will
be shown as Group , where name
is the URL associated with an applet.
Individual listings of threads will
show the thread name, the thread
priority, alive if the thread is alive
or destroyed if the thread is in the
process of being destroyed, and daemon
if the thread is a daemon thread.

The other command that I’ve used most often from that console is the trace level from 0-5:

This sets the trace-level options as described in the next section, Tracing and Logging.

From that page, you’ll see that the levels look like this:

• 0 — off
• 1 — basic
• 2 — network, cache, and basic
• 3 — security, network and basic
• 4 — extension, security, network and basic
• 5 — LiveConnect, extension, security, network, temp, and basic

These tools can all be fairly useful as you’re trying to unravel what in the world has gotten into the head of your applets. I know that they’ve worked for me.