What does it mean by adding parameter "-classic" into java VM?

[Javan Li]

Thanx!

[Mani Ram]

The Java 2 SDK and Java 2 Runtime Environment contain two implementations of the Java virtual machine.
a) The Java HotSpotTM Client VM
b) The Java 2 Classic VM
The default VM is the HotSpot. When -classic option is used, it invokes the Classic VM.

[Igor Ko]

In java 1.4.1 isn't such option, instead you
can use:
-Xint
Operate in interpreted-only mode. Compilation to native code is disabled, and all bytecodes are executed by the interpreter. The performance benefits offered by the Java HotSpot Client VM's adaptive compiler will not be present in this mode.

[Javan Li]

What 'd difference between classic and HotSpot VM??Thanx!

[Marilyn de Queiroz]

Hot Spot generally runs your code faster.

[Gregg Bolinger]

HotSpot is what is considered a "Look Ahead" Interpretor. It takes your byte code and takes it down to native code before executing so that it actually executes faster. This instead of interpreting one line at a time and executing that way.
A little simpler than what actually happens, but I believe that is the idea.

[Blair Spencer]

Hmmm,
So is there a difference between the "look ahead" method file and a machine code file?
I mean, are we compiling to the point that there wouldn't be x-platform portability at all?
If so, there are times I would sacrifice the speed...if not, why ever use the classic (or Xint)?