Java, C and C++ are programming languages.  The only memory they consume
is in programmers' heads.

Programs written using Java, C and C++ consume memory when run on a
computer.  In general, it is difficult to say anything of substance
about the comparative memory usage of such programs.  The choice of
programmer is much more important than the choice of language in this
regard.

Ray

The short answer is yes.

The long answer is yes but, with a few exceptions, it probably doesn't  
matter.

For some tasks it is even claimed that Java can exceed C++ performance in  
long-running applications because the virtual machine is able to optimise  
at runtime.  And, of course, many applications are I/O bound, in which  
case it really doesn't matter what language you use as it will not be the  
limiting factor.

Do you have an existing Java program that you want to run?  Or do you want  
to write a Java program to accomplish some particular task?

Dan.

I'm going to do a little Q and A session myself here to spead this thread up
a bit. The conclusion is that there is no easy answer.

Q: Do Java programs consume more memory/CPU than C/C++ programs?
A: Not nescessarily. There exists Java programs which consume less memory
and CPU power than C/C++ programs. "Hello World" written in Java, for
example, consumes less memory and CPU and Doom 3 written in C++.

Q: Will a Java program consume more memory/CPU than a C/C++ program which
does the same thing?
A: Not nescessarily. I could write a really crappy implementation of "Hello
World" in C++ that requirs 2 gigs of RAM and 3 teraops to run.

Q: If you take the source code a C/C++ program, and compile it using Java,
will the resulting Java program require more memory/CPU time than its C/C++
counterpart?
A: The source code for a C/C++ program probably will not compile with a Java
compiler.

Q: If you take a C/C++ source code program, translate it to Java, will the
resulting Java program require more memory/CPU time than its C/C++
counterpart?
A: Not nescessarily, as there isn't a one-to-one mapping between C/C++
source code and Java source code. I could do a really crappy job of
translating, as above.

Q: Take two similar programs; One written in C/C++, and one written in Java.
Which one will run faster?
A: See this thread:
http://groups.google.ca/group/comp.lang.java.programmer/browse_frm/thread/81f800
895f31cdf1/cb5cfa858f8e09c5

   - Oliver