Originally posted by Namaste Sathi:
hi all,
i am a novice in this JAVA world. went throgh a couple of books trying to understand all these JAVA jargons. could someone please explain me what these JVM and JRE are in simple way and how these two are related.
how java is PORTABLE. saw that java is "write once, run everywhere". what does it mean? how and what makes this possible? what are some of languages that are not portable?
JVM is the Java Virtual Machine. It is the thing that takes the class files and makes them run on whatever machine you are using.
JRE is the Java Runtime Environment. It includes a JVM and all the other stuff (like the standard class libraries) that you need to run Java code.
Originally posted by Namaste Sathi:
For example, i have a hello.class. now if i would like to run this hello.class in another machine, that machine must have JVM to understand this hello.class. how does that machine alreaddy gets JVM in it? or must JVM go to that machine with hello.class?
I am not insane. The voices in my head told me so.
Ron Newman - SCJP 1.2 (100%, 7 August 2002)
Originally posted by Steve Schowiak:
One of the few problems with Java is that it is VERY SLOW. Because the JVM must step through the bytecode in the class files, interpret the code, then perform the actions the bytecode calls for, it is very slow.
COMPILED languages like C++ are very fast in comparison. C++ generates an executable .exe file that runs without an interpretor.
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