Miscellaneous I

and the stand alone JRE?

Can someone tell me the difference between the JRE that comes with the J2SDK

and the stand alone JRE? When should I use which? I read the sun s web page and

they said the the JRE stand alone package is for shipping your application, it doesn t

come with a compiler nor debugger, but what does it really mean?

Answer: Exactly that. The Java 2 SDK (aka JDK) is the JRE plus the compiler (javac)

and debugger (jdb). The JRE is entirely sufficient to run a Java application (with a

couple exceptions in situations where you call into the compiler or some such). It s

entirely redistributable with your Java application if you ve written an app in Java

intended for an audience that may not have the JRE installed.

Chris Smith

 Q: Does anyone know of a java machine that will run from a 1.44Mb Floppy? I

have an application I want to run from a dos 7.1 floppy disk.

Answer: please check here:

http://www.transvirtual.com/kaffe features.htm

there is written: 

"Efficiency is not just about execution speed, but Kaffe s JIT is quite speedy: it runs

Java code only 30% slower than plain C. Such things  as memory consumption of a

JIT enabled, graphical Kaffe are also important. 

Here we can execute a full system on a 4 MB DOS system, and the VM and library 

footprint won t exceed 1 MB. Our complete source tree fits on a single 1.4 MB floppy.

This is what we mean by "efficiency".

Good enough for you?

Q: Anybody know a good tool to distribute your made java classes with for

windows platforms?

I want to create a setup file that alse verifies existence of java runtimes etc etc and

creates a shortcut and that kinda things...I tried looking into Wise installation systems

and Installshield asswel, but they are both not really build for this kinda things...

Answer: You should try, InstallAnywhere by ZeroG (http://www.zerog.com)

ZeroG has a free version call, "InstallAnywhere NOW". You should give it a try, its a

really easy to use java installer. It has all the features you need, such as creating an

Icon on your desktop, creating a folder under the Windows "Start" button, it can be

set to have the user search for a JVM on their computer, and much much more... (I

sound like a commercial, hehehe)

JHig310336

 Q: Heap size limit!! I am running JVM from JDK 1.2 on Solaris 2.7 and I couldn t

allocate the max heapsize over 2G when I invoke the JVM.

I have repetive tasks that take 500m memory each to run, so I naturally want to run

as many threads as possible. I figured out this 2G ( mx2047m) limit by trial and error

but is there any way out of this? My workstation happen to have 2G physical

memory, and the file size limit is 2G as well (from ulimit), are there any co relation

among those numbers?

Answer: Yes, there is a relation: both result from limiting addressing space to what

you can get with signed 32 bit ints for addresses:

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