On Java and C++

[wellstone9912]

Java programmers seem to always be whining about how confusing and
overly complex C++ appears to them. I would like to introduce an
explanation for this. Is it possible that Java programmers simply
aren't smart enough to understand C++?

This is not merely a whimsical hypothesis. Given my experience with
Java programmers --- the code they write and the conversations they
have --- Occam's Razor points to this explanation. For example,

"Oooh I'm confused about the difference between pointers, references,
and objects! How confusing!"

"Oooh operator overloading confuses me! The expression x + y is so
confusing, who knows what's happening with that? If x and y are
complex numbers, what the hell could x + y mean?"

"Oooh multiple inheritance is so confusing! Though I am both a father
and a programmer, I still find it so confusing how the same object can
be two different things! How confusing!"

"Oooh and virtual bases are so bizarre! I am a student --- myself
'the father' is the same student as myself 'the programmer' --- but
nonetheless the idea of virtual bases is absolutely confounding and
confusing to me!"

Again, Occam's Razor is a valuable tool here. In deciding among
competing hypotheses, choose the simplest one. To impartial observers
of indoctrinated Java programmers, the explanation is simple indeed.

[The Ghost In The Machine]

In comp.lang.java. advocacy, Remon van Vliet
<re***@exmachin a.nl>
wrote
on Thu, 27 Apr 2006 20:44:11 +0200
<44************ ***********@new s.xs4all.nl>:

"Walter Bright" <wa****@digital mars-nospamm.com> wrote in message
news:Dc******** *************** *******@comcast .com...

Noah Roberts wrote:

Roedy Green wrote:
On Thu, 27 Apr 2006 15:06:53 +0200, "Gernot Frisch" <[e-mail] >
wrote, quoted or indirectly quoted someone who said :

Mixing exception handling and memory management boggles the human
mind.

Only one incapable of learning very simple techniques to make it a
non-issue.

http://www.hackcraft.net/raii/

There's another way to do it - scope guard. Here's an article on it:
http://www.digitalmars.com/d/exception-safe.html

-Walter Bright
www.digitalmars.com C, C++, D programming language compilers

What point am i missing if i mention the "finally" block in Java?

"finally" is to RAII as manual transmission is to
automatic, from the looks of things.

--
#191, ew****@earthlin k.net
Windows Vista. Because it's time to refresh your hardware. Trust us.

[Chris Smith]

Remon van Vliet <re***@exmachin a.nl> wrote:

Have you ever used Java and actually ran into an issue that requires
RAII?

Of course no one has. There are no issues that require RAII. That's
irrelevant to the question of whether it is useful. Certainly,
try/finally gets cumbersome sometimes.

--
www.designacourse.com
The Easiest Way To Train Anyone... Anywhere.

Chris Smith - Lead Software Developer/Technical Trainer
MindIQ Corporation

[Chris Smith]

> Roedy Green wrote:

Mixing exception handling and memory management boggles the human
mind.

Noah Roberts <ro**********@g mail.com> wrote: Only one incapable of learning very simple techniques to make it a
non-issue.

http://www.hackcraft.net/raii/

There are two questions being considered simultaneously here. One is
what is required to produce useful software in a language. The other
matter is what is required to understand that language. I side with the
position that a language that's hard to understand has a weakness in
this even if it remains possible to write software using that language.
Exception handling and memory management IS tricky in C++. So is the
relationship between function overloading, implicit type conversions,
and templates.

RAII is a different matter. It's a nice feature to have; but it doesn't
make the language any easier to understand.

--
www.designacourse.com
The Easiest Way To Train Anyone... Anywhere.

Chris Smith - Lead Software Developer/Technical Trainer
MindIQ Corporation

[Noah Roberts]

Chris Smith wrote:

Roedy Green wrote:

Mixing exception handling and memory management boggles the human
mind.

Noah Roberts <ro**********@g mail.com> wrote:

Only one incapable of learning very simple techniques to make it a
non-issue.

http://www.hackcraft.net/raii/

There are two questions being considered simultaneously here. One is
what is required to produce useful software in a language. The other
matter is what is required to understand that language. I side with the
position that a language that's hard to understand has a weakness in
this even if it remains possible to write software using that language.
Exception handling and memory management IS tricky in C++. So is the
relationship between function overloading, implicit type conversions,
and templates.

Lots of silly statements but no backing. "X is hard." Meaningless.
RAII is a different matter. It's a nice feature to have; but it doesn't
make the language any easier to understand.

Actually, RAII is at the HEART of this matter as it is a commonly used
technique to deal with the issue put forth. It is a very simple
concept and it works not only for memory management but also any other
resource that needs to be aquired and released.

[Walter Bright]

Remon van Vliet wrote:

"Walter Bright" <wa****@digital mars-nospamm.com> wrote in message
news:Dc******** *************** *******@comcast .com...

Noah Roberts wrote:

Only one incapable of learning very simple techniques to make it a
non-issue.

http://www.hackcraft.net/raii/

There's another way to do it - scope guard. Here's an article on it:
http://www.digitalmars.com/d/exception-safe.html

What point am i missing if i mention the "finally" block in Java?

'finally' works fine for one level of undo. It doesn't work so well (and
neither does RAII) if there are multiple operations that must all
succeed or none have happened. For example, if a transaction consists of
transactions A, B, and C, and A and B succeed but C fails, one must
unwind B and C. The article goes into more depth with this including
examples.

-Walter Bright
www.digitalmars.com C, C++, D programming language compilers

[Walter Bright]

Noah Roberts wrote:

Also, you could read that article above which shows some shortcommings
of both RAII and finally. However, the "scope guard" appears to be a D
language particular construct so is rather moot in this discussion.

There's a link at the end of the article with Andrei Alexandrescu's
technique for doing a limited form of scope guard in C++.

http://www.digitalmars.com/d/exception-safe.html

-Walter Bright
www.digitalmars.com C, C++, D programming language compilers

[Bent C Dalager]

In article <44************ ***********@new s.xs4all.nl>,
Remon van Vliet <re***@exmachin a.nl> wrote:

We're all aware Javascript is completely unrelated to Java right?

Well, "completely unrelated" may be going a bit too far (it's more
like the wayward half brother that comes around to borrow money from
you every now and then, who you don't like to talk about in polite
company) but it is definately a different language.

Cheers
Bent D
--
Bent Dalager - bc*@pvv.org - http://www.pvv.org/~bcd
powered by emacs

[Martin Vejnár]

Remon van Vliet wrote:

Have you ever used Java
No
and actually ran into an issue that requires RAII?

Require is a strong word. You can always do without RAII. You just have
a greater chance of losing precious time trying to figure out where
exactly have you forgotten to release that mutex...

Garbage collector may be good when it comes to releasing memory, but
memory is not the only resource you use. How about files, network
streams, database connections, synchronization primitives, etc?

A reply from "The Ghost In The Machine" has mentioned try..finally.
Whenever you use that construct to safely dispose of a resource, you're
better off using RAII.

Btw, I'm not really sure, but is the finally block executed, when you do
'return' from inside the try block?

--
Martin

[Bent C Dalager]

In article <e2**********@s olaris.cc.vt.ed u>, Ben <be******@vt.ed u> wrote:

I've programmed both in JAVA and C++

Try writing a OS in JAVA...wait is that even possible?

This is easily possible (and reasonably common) on smart card chips,
many of which support Java bytecode natively.

Java-based CPUs for desktops have been tried I think, but it didn't
take off.

Cheers
Bent D
--
Bent Dalager - bc*@pvv.org - http://www.pvv.org/~bcd
powered by emacs

[Alf P. Steinbach]

* Walter Bright:

Noah Roberts wrote:

Also, you could read that article above which shows some shortcommings
of both RAII and finally. However, the "scope guard" appears to be a D
language particular construct so is rather moot in this discussion.

There's a link at the end of the article with Andrei Alexandrescu's
technique for doing a limited form of scope guard in C++.

http://www.digitalmars.com/d/exception-safe.html

I think you should get the attributions right (sorry, how could I put
this in a more gentle way?): ScopeGuard was Petri Marginean's invention,
and he co-authored the CUJ article with Andrei.

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