Re: How do you choose your programming language ?

On Wed, Nov 23, 2005, Tzahi Fadida wrote about "RE: [hackers-il] How do you 
choose your programming language ?":
> I am not sure you are correct. I believe that in latest java there is a trick 
> with
> the classloader that you can allocate and free objects, however I heard
> that it can lead to memory leak (whats new).

Any language is Turing-complete, and if you realy try very hard, you CAN
allocate and free memory, perhaps by using class-loaders, or perhaps by
using JNI (i.e., C code). But doing this is extremely complex, and goes
against the entire design of the language. It's almost like buying a plane,
and then taking off its wings and trying to modify its engine to be more
fuel-efficient - why don't you buy a car instead?
Nobody programs the way you describe in Java, except perhaps as an excercise.
If someone wants to write this way, they just switch to C or whatever.

> I also heard that there are alternative
> GC and that there are calls that can expedite GC.

For the object creation patterns that are common in Java (myriads of short-
lived objects, Java's current GC ("hotspot") is extremely efficient in speed,
because allocations are extremely quick (no need to "search the heap" for
holes like in C, just increment the pointer), even in a multi-threaded
program, and free doesn't take any time (the time of GC is not proportional
to the number of dead objects, but rather to the number of living objects).

I wonder, though, if anybody attempted to do a reference-counting GC for
Java (do you know of such a thing?). It would have been much slower than the
current GC, but perhaps waste much less memory. For many applications,
this could have been a win.

> Anyway, as I mentioned before there are native compilers that makes all these
> a mute discussion, e.g. GCJ. And, its FOSS.

I completely fail to understand this statement. Please enlighten me.
Even if gcj compiles codes, it still has to use garbage collection, because
in Java all parameters are "passed by reference" (except for primitive types
like "int"), and anybody can save these references and use them later, and
stop using them much later. Except a few optimizations (like immediately
freeing an object which was never passed anywhere), I don't see what you
can do to improve memory waste by dead objects. And these optimizations
are not specific to a compiler, anyway.

> Personally the most important reason I like JAVA is that you can find the 
> bugs quickly
> and develop quickly using Jbuilder which is the best (although you have to 
> pay).

I use eclipse, which is probably the most convenient development environment
I've seen. I agree, it's much more fun to program in Java than in C or C++.
BUT, the sad truth is that often when you finish the project and see how
the result behaves, you wish you spent the time on writing the project in
a different language :(

Ok, that has been the end of my gripes about Java for today. Sorry :-)


-- 
Nadav Har'El                        |   Thursday, Nov 24 2005, 22 Heshvan 5766
nyh-TS7m/3hpY0sOpacJJkBjfT4kX+cae0hd@xxxxxxxxxxxxxxxx             
|-----------------------------------------
Phone +972-523-790466, ICQ 13349191 |Time is the best teacher. Unfortunately
http://nadav.harel.org.il           |it kills all its students.


------------------------ Yahoo! Groups Sponsor --------------------~--> 
Get fast access to your favorite Yahoo! Groups. Make Yahoo! your home page
http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/saFolB/TM
--------------------------------------------------------------------~-> 

 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/hackers-il/

<*> To unsubscribe from this group, send an email to:
    hackers-il-unsubscribe-hHKSG33TihhbjbujkaE4pw@xxxxxxxxxxxxxxxx

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/