Firefox Addon: User Agent Switcher

If you are using the User Agent Switcher add-on with Firefox, and find it pesky to reset the user agent every time when the browser restarts, here is a trick:

1. Open the configuration tab in your FF by typing "about:config" in the URL bar.
2. Add the following attribute and value.

useragentswitcher.reset.onclose = false

3. Done!

Java Application Launcher's Options

-Dproperty=value
Set a system property value. If value is a string that contains spaces, you must enclose the string in double quotes:
java -Dfoo="some string" SomeClass

For options start with X, they are non-standard options.

http://download.oracle.com/javase/1.5.0/docs/tooldocs/windows/java.html

Difference bewteen 3-tier and MVC architecture

At first glance, the three tiers may seem similar to the model-view-controller (MVC) concept; however, topologically they are different. A fundamental rule in a three tier architecture is the client tier never communicates directly with the data tier; in a three-tier model all communication must pass through the middle tier. Conceptually the three-tier architecture is linear. However, the MVC architecture is triangular: the view sends updates to the controller, the controller updates the model, and the view gets updated directly from the model.