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This bug takes the cake!
Message
Information générale
Forum:
Internet
Catégorie:
Autre
Divers
Thread ID:
00302159
Message ID:
00308229
Vues:
39
>>Ain't Java wunnerful?
>
>for such a short little word, it sure is a pain in the butt. & I dont really get this whole VM (Virtual Machine) thing. Oh wise one... what the hell is a VM anyway?!? Some sort of halfbreed compiler or runtime library?

Java once compiled supposedly 'runs on all supported systems'. It does this by generating pcode, which is then executed by a Java 'virtual machine' that implements a standard set of services. The virtual machine implements the instructions on the target platform. That's how the same emitted code can run on a Mac based on a PowerPC RISC chip under MacOS, a Sun under the ?nix-du-jour and a Wintel platform box under < cough > Win2K. Each has it's own virtual engine that implements the standard machine whose instructions are emitted by the Java compiler.

If you ever dealt with UCSD Pascal, SSDD (Same Stuff, Different Day.) It means emulation.

Needless to say, performance-oriented Java compilers also give an option of emitting native code, but alas, emitted native code for the Mac won't run on the freaking 486 in the back room under Win95. One of the first things out of a Java programmer's mouth when switching to a new platform is usually "Does the compiler emit native code?"
EMail: EdR@edrauh.com
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"No, the horizon is moving up!"
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NT and Win2K FAQ .. cWashington WSH/ADSI/WMI site
MS WSH site ........... WSH FAQ Site
Wrox Press .............. Win32 Scripting Journal
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