-----Original Message----- From: csappenfield
----- Original Message ----- From: Jonathan Hutchins
On Thursday 17 February 2005 03:42 pm, Jeremy Turner wrote:
On Thu, Feb 17, 2005 at 11:08:53AM -0600, Jonathan Hutchins wrote:
Java is a virtual operating system that can be installed on
top of
other operating systems. As an OS, it's somewhat limited and specialized, but that's what the "Virtual Machine" in
java is all
about.
I wouldn't call Java an operating system, in the typical sense
of the
word.
I again refer you to the concept of the Java Virtual Machine.
A JVM is an abstraction of an OS, just as an OS is an abstraction of your hardware. To say one is the other makes no sense.
All semantics and definitions aside. Let's look at what Java really *does* and then compare it to what AIX does and then let's decide if Java is an OS or not. 1) Java runs as a virtual machine on top of some other layer that eventually has access to the hardware; AIX runs as a virtual machine on top of some other layer that eventually has access to the hardware. 2) One can write programs in Java; one can write programs in AIX. 3) Programs can be "compiled" in Java ; programs can be compiled in AIX. 4) Java can only compile and run Java programs ; AIX can compile and run multiple programming language programs. 5) ? ; AIX can run virtual machines inside of AIX. 6) ? ; AIX can run and control many programs simultaneously. ...
Item number 4 and beyond shows us that Java is not an "OS". While it is possible to emulate compiling and running a COBOL program in Java you can't really do it. Additionally there are many other tasks that real operating systems do that Java really can't do. Java isn't an OS, it is a VM that runs on top of an OS. While there are many things you could do in Java that would make you feel that Java is an OS, there are just too many things that Java can't do. Compare the Linux kernel (even version 1) with Java and you'll see why Java is a VM and not an OS. VM <> OS VM = VM
Java is more than a programming language, but less than an OS.
Brian Densmore