ADA vs Java

ADA vs Java

[Ted]

Writing code in ADA 95 and compiling it for the JVM should produce more
reliable code than writing in Java 2. Does anyone know any good technical
reasons for prefering Java?

Re: ADA vs Java

[Eric Sosman]

Ted wrote:
> Writing code in ADA 95 and compiling it for the JVM should produce more
> reliable code than writing in Java 2. Does anyone know any good technical
> reasons for prefering Java?

    All published studies[1] of the reliability of Ada and
Java programs have consistently found that Java is between
86.3% and 87.7% more reliable than Ada.[2]

    [1] Sample size N = 0, AFAIK.

    [2] 94.2% of all statistics quoted on Usenet are bogus.

    (In other words: Are there any objective data to support
the opinion that either Ada or Java is "more reliable" than
the other?  Surveys, experiments, studies, ...?)

-- 
Eric.Sosman@sun.com

Re: ADA vs Java

[Pascal Obry]

Eric Sosman <eric.sosman@sun.com> writes:

>     (In other words: Are there any objective data to support
> the opinion that either Ada or Java is "more reliable" than
> the other?  Surveys, experiments, studies, ...?)

Probably SUN has. The license quote explicitly that Java MUST NOT be used to
control nuclear power plant for example. No Ada vendors are saying that Ada
must not be used for safety critical projects. Don't you think this is
related to safety/reliability ?

Pascal.

-- 

--|------------------------------------------------------
--| Pascal Obry                           Team-Ada Member
--| 45, rue Gabriel Peri - 78114 Magny Les Hameaux FRANCE
--|------------------------------------------------------
--|              http://www.obry.net
--| "The best way to travel is by means of imagination"
--|
--| gpg --keyserver wwwkeys.pgp.net --recv-key C1082595

Re: ADA vs Java

[Stefan Schulz]

On Sat, 18 Jun 2005 10:23:32 +0200, Pascal Obry wrote:

> 
> Eric Sosman <eric.sosman@sun.com> writes:
> 
>>     (In other words: Are there any objective data to support
>> the opinion that either Ada or Java is "more reliable" than
>> the other?  Surveys, experiments, studies, ...?)
> 
> Probably SUN has. The license quote explicitly that Java MUST NOT be used to
> control nuclear power plant for example. No Ada vendors are saying that Ada
> must not be used for safety critical projects. Don't you think this is
> related to safety/reliability ?

It merely means that they want to be absolutely positively sure that noone
will sue them over a bug in the compiler. IIRC, you will find a similar
clause in Mircosofts C/C++ Compilers license es well.

-- 
In pioneer days they used oxen for heavy pulling, and when one ox
couldn't budge a log, they didn't try to grow a larger ox. We shouldn't
be trying for bigger computers, but for more systems of computers.
           --- Rear Admiral Grace Murray Hopper

Re: ADA vs Java

[Larry Kilgallen]

In article <pan.2005.06.18.11.20.22.386912@spacetime.de>, Stefan Schulz <terra@spacetime.de> writes:
> On Sat, 18 Jun 2005 10:23:32 +0200, Pascal Obry wrote:
> 
>> 
>> Eric Sosman <eric.sosman@sun.com> writes:
>> 
>>>     (In other words: Are there any objective data to support
>>> the opinion that either Ada or Java is "more reliable" than
>>> the other?  Surveys, experiments, studies, ...?)
>> 
>> Probably SUN has. The license quote explicitly that Java MUST NOT be used to
>> control nuclear power plant for example. No Ada vendors are saying that Ada
>> must not be used for safety critical projects. Don't you think this is
>> related to safety/reliability ?
> 
> It merely means that they want to be absolutely positively sure that noone
> will sue them over a bug in the compiler. IIRC, you will find a similar
> clause in Mircosofts C/C++ Compilers license es well.

"Sue them over a bug in the compiler" certainly seems related to
safety/reliability.  I doubt the suit would be over trademark misuse.

I am not sure how the statement about Microsoft C/C++ is related.
The question was about Ada vs. Java.  So which Ada compilers have
such a restriction ?

Re: ADA vs Java

[HansF]

On Sat, 18 Jun 2005 07:13:58 -0500, Larry Kilgallen interested us by
writing:

> 
> "Sue them over a bug in the compiler" certainly seems related to
> safety/reliability.  I doubt the suit would be over trademark misuse.
> 
> I am not sure how the statement about Microsoft C/C++ is related.
> The question was about Ada vs. Java.  So which Ada compilers have
> such a restriction ?

The following deals with typical commercial software companies:

You will find that many 'modern companies' have contracts and disclaimers
that are created by their lawyers.  They have nothing to do with 'actual'
safety and reliability and everything to do with 'potential' safety and
reliability.  

(Just because a bug has not been found, that does not imply that the
software is totally bug free.  And even if it is bug free, are there
'exceptional results' which may be found, possibly at previously
undiscovered boundary conditions?)

Without such statements, companies must include the possibility of a
lawsuit due to error or negligence as a risk factor in their SEC-filed
financial statement.  And then analysts look at the total risk factors and
'determine' the possible stock price.  The stock price, of course, tells
us which are 'good' companies.  (Good, perhaps meaning, those who have
enough disclaimers to avoid risk-based lawsuits?)

The previous post mentioned Microsoft C/C++ simply to indicate that the
practise of using such disclaimers is not unusual.

Barring such a blanket disclaimer, the company's insurance would expect
a documented test suite that demonstrates how the product handles a
variety of possible failure conditions.  Even then, the company will
frequently add a disclaimer limiting liability if the product is used
outside the scope of the demonstrated test cases.

Bottom line - read your license agreement.  Especially the fine print.


-- 
Hans Forbrich                           
Canada-wide Oracle training and consulting
mailto: Fuzzy.GreyBeard_at_gmail.com   
*** I no longer assist with top-posted newsgroup queries ***

Re: ADA vs Java

[Preben Randhol]

On Sat, Jun 18, 2005 at 09:46:34PM +0000, HansF wrote:
> 
> The following deals with typical commercial software companies:
> 
> You will find that many 'modern companies' have contracts and disclaimers
> that are created by their lawyers.  They have nothing to do with 'actual'
> safety and reliability and everything to do with 'potential' safety and
> reliability.  
> 
> (Just because a bug has not been found, that does not imply that the
> software is totally bug free.  And even if it is bug free, are there
> 'exceptional results' which may be found, possibly at previously
> undiscovered boundary conditions?)

Yes, sure, but this is beside the point. The point is: Do you think C++
or Java is a suitable language to run a nuclear power station? I
wouldn't use neither, not for possible compiler bugs, but because of the
languages themselves.

Preben
-- 
Preben Randhol -------------- http://www.pvv.org/~randhol/Ada95 --
                 �For me, Ada95 puts back the joy in programming.�

Re: ADA vs Java

[Pascal Obry]

Stefan Schulz <terra@spacetime.de> writes:

> It merely means that they want to be absolutely positively sure that noone
> will sue them over a bug in the compiler. IIRC, you will find a similar
                     ^^^^^

Exactly my point, thanks.

Pascal.

-- 

--|------------------------------------------------------
--| Pascal Obry                           Team-Ada Member
--| 45, rue Gabriel Peri - 78114 Magny Les Hameaux FRANCE
--|------------------------------------------------------
--|              http://www.obry.net
--| "The best way to travel is by means of imagination"
--|
--| gpg --keyserver wwwkeys.pgp.net --recv-key C1082595

Re: ADA vs Java

[HansF]

On Sat, 18 Jun 2005 16:09:48 +0200, Pascal Obry interested us by writing:

> 
> Stefan Schulz <terra@spacetime.de> writes:
> 
>> It merely means that they want to be absolutely positively sure that noone
>> will sue them over a bug in the compiler. IIRC, you will find a similar
>                      ^^^^^
> 
> Exactly my point, thanks.
 
Are you implying that no Ada compiler has any bugs?

-- 
Hans Forbrich     

Re: ADA vs Java

[Pascal Obry]

HansF <News.Hans@telus.net> writes:

> Are you implying that no Ada compiler has any bugs?

Building safety-critrical software is possible in Ada and no Ada vendor will
have such disclamer (Ada is used in the most critical application around). The
point is that Ada can be used with a certified runtime or no runtime at all
in some implementation.

Pascal.

-- 

--|------------------------------------------------------
--| Pascal Obry                           Team-Ada Member
--| 45, rue Gabriel Peri - 78114 Magny Les Hameaux FRANCE
--|------------------------------------------------------
--|              http://www.obry.net
--| "The best way to travel is by means of imagination"
--|
--| gpg --keyserver wwwkeys.pgp.net --recv-key C1082595

Re: ADA vs Java

[HansF]

On Sun, 19 Jun 2005 08:42:34 +0200, Pascal Obry interested us by writing:

> 
> Building safety-critrical software is possible in Ada and no Ada vendor will
> have such disclamer (Ada is used in the most critical application around). The
> point is that Ada can be used with a certified runtime or no runtime at all
> in some implementation.
> 
> Pascal.

No doubt Ada is solid.  Little wonder that Oracle's PL/SQL is based on
Ada.  

<opinion>
In my opinion, based on my experience, Ada will tend to be used in a
professional environment tht includes proper analysis, specification and
testing. As such, the attitude in an Ada environment may be as much or
more important to critical programming than the fact that it is a solid
piece of technology.
</opinion>

But you do not answer the question, which is (rephrased): "Are you
implying that there are no bugs in any Ada compiler?".  

(If you answer yes, the next obvious question is - what is the proof. 
However, I will not ask that question! <g>)

-- 
Hans Forbrich     

Re: ADA vs Java

[Pascal Obry]

HansF <News.Hans@telus.net> writes:

> But you do not answer the question, which is (rephrased): "Are you
> implying that there are no bugs in any Ada compiler?".  

I did not answer this question because it is not a question, I mean you pretty
well know the answer. All piece of software has bugs. But softwares built with
Ada tends to have far less bugs per sloc than other languages. See recent
thread on comp.lang.ada for ref documents.

Pascal.

-- 

--|------------------------------------------------------
--| Pascal Obry                           Team-Ada Member
--| 45, rue Gabriel Peri - 78114 Magny Les Hameaux FRANCE
--|------------------------------------------------------
--|              http://www.obry.net
--| "The best way to travel is by means of imagination"
--|
--| gpg --keyserver wwwkeys.pgp.net --recv-key C1082595

Re: ADA vs Java

[Alan Krueger]

Pascal Obry wrote:
> HansF <News.Hans@telus.net> writes:
>>But you do not answer the question, which is (rephrased): "Are you
>>implying that there are no bugs in any Ada compiler?".  
> 
> I did not answer this question because it is not a question, I mean you pretty
> well know the answer. All piece of software has bugs. But softwares built with
> Ada tends to have far less bugs per sloc than other languages.

You appear to be equating compiler bugs with quality of code implemented 
in the language.

Re: ADA vs Java

[Pascal Obry]

Alan Krueger <wgzkid502@sneakemail.com> writes:

> You appear to be equating compiler bugs with quality of code implemented in
> the language.

No I did not mean that. I'm not sure there is relation between both except
when a C compiler is built in C, and Ada compiler built in Ada...

Pascal.

-- 

--|------------------------------------------------------
--| Pascal Obry                           Team-Ada Member
--| 45, rue Gabriel Peri - 78114 Magny Les Hameaux FRANCE
--|------------------------------------------------------
--|              http://www.obry.net
--| "The best way to travel is by means of imagination"
--|
--| gpg --keyserver wwwkeys.pgp.net --recv-key C1082595

Re: ADA vs Java

[HansF]

On Mon, 20 Jun 2005 08:30:02 +0200, Pascal Obry interested us by writing:

> 
> I did not answer this question because it is not a question, I mean you pretty
> well know the answer. All piece of software has bugs. But softwares built with
> Ada tends to have far less bugs per sloc than other languages. See recent

The question was originaly rhetorical - you claimed earlier that the
standard disclaimer was related to safety and reliability, and now you
acknowledge that Ada has bugs (at least potentially), but does not have a
disclaimer, and therefore does not make the user aware of *possible*
deficiencies. I see the potential for a lawsuit in any decently litigious
society.

To conclude and summarize my points:

- the reason for the disclaimer by many large software organizations is to
avoid legal repercussions.  It has nothing to do with the quality of the
compiler, nor the quality of the resultant code; and

- it may be that the attitiude of the Ada community, with respect to
thorough analysis and test cases, is the significant contributor to the
use of Ada in critical environments, rather than the compiler itself.


The reason I am driving on this - I pay large quantities of money to an
insurance company to cover myself as a consultant in the instance that I
could be sued due to an unforeseen (not even deliverate) error or
ommission.  This, and my standard contract disclaimer, simply means that I
do not wish to waste all on a lawsuit - but it does NOT reflect on the
quality I deliver.

-- 
Hans Forbrich                           

Re: ADA vs Java

[Preben Randhol]

On Mon, Jun 20, 2005 at 10:31:46PM +0000, HansF wrote:
> 
> - the reason for the disclaimer by many large software organizations is to
> avoid legal repercussions.  It has nothing to do with the quality of the
> compiler, nor the quality of the resultant code; and

So your saying: Use Java, C++ etc... for safety-critical applications.
The reason for the warning NOT to do so is purly legal protection and it
is not due to that the languages are not suited for the task?

About Ada and Java you can have a look at what Duncan Sands have to say
about their system. They use both languages, but Java only for the GUI.

http://www.gnat.com/aa_videos.php#

> - it may be that the attitiude of the Ada community, with respect to
> thorough analysis and test cases, is the significant contributor to the
> use of Ada in critical environments, rather than the compiler itself.

Please read up on Ada so you can put the languages perspective.
Have a look at SPARK too.

> The reason I am driving on this - I pay large quantities of money to an
> insurance company to cover myself as a consultant in the instance that I
> could be sued due to an unforeseen (not even deliverate) error or
> ommission.  This, and my standard contract disclaimer, simply means that I
> do not wish to waste all on a lawsuit - but it does NOT reflect on the
> quality I deliver.

This may cover ones back, but do one want the insurance company to bail
one out again and again because one use a tool that will more likely
make one generate errors? I would guess the premium would rise over
time...

-- 
Preben Randhol -------------- http://www.pvv.org/~randhol/Ada95 --
                 �For me, Ada95 puts back the joy in programming.�

Re: ADA vs Java

[Leif Roar Moldskred]

Preben Randhol <randhol+cla@pvv.org> writes:
 
> So your saying: Use Java, C++ etc... for safety-critical applications.
> The reason for the warning NOT to do so is purly legal protection and it
> is not due to that the languages are not suited for the task?

Actually, I think he is correct in his surmise. This is a boilerplate
warning that's slapped on to limit liability and it says more about
whether Sun consider safety critical system a target _market_ for Java
than whether they consider Java _suitable_ for such code. (Of course,
Java isn't suitable for safety critical systems, which is probably
part of the reason why Sun doesn't consider such a target market.)

Like with "No user serviceable parts inside" and similar warning
labels, the issue is what the provider guarantees for their product,
and not really what the product is. "No user serviceable parts inside"
doesn't actually mean there isn't any parts you can't service yourself
(there might or there might not be.) Rather, it means "We have not
designed this product for you to service the parts yourself; so if you
try, don't come crying to us if you break something."

-- 
Leif Roar Moldskred
Got Sfik?

Re: ADA vs Java

[Preben Randhol]

On Tue, Jun 21, 2005 at 11:47:09AM +0200, Leif Roar Moldskred wrote:
> Preben Randhol <randhol+cla@pvv.org> writes:
>  
> > So your saying: Use Java, C++ etc... for safety-critical applications.
> > The reason for the warning NOT to do so is purly legal protection and it
> > is not due to that the languages are not suited for the task?
> 
> Actually, I think he is correct in his surmise. This is a boilerplate
> warning that's slapped on to limit liability and it says more about
> whether Sun consider safety critical system a target _market_ for Java
> than whether they consider Java _suitable_ for such code. (Of course,
> Java isn't suitable for safety critical systems, which is probably
> part of the reason why Sun doesn't consider such a target market.)

If Sun wanted to cover themselves legally they could have simply stated
that you use the language and compiler at your own risk and that they
cannot guarantee that the produced code is correct or acting as
intended. The point that they especially writes that one should use it
for situation X and Y means to me that they do think their product IS
NOT suitable to be use in situation X and Y. 

My point is simply:

1. They don't want people to use the compiler/language for X and Y
2. They don't want lawsuits due to bugs in compiler/language generally

> Like with "No user serviceable parts inside" and similar warning
> labels, the issue is what the provider guarantees for their product,
> and not really what the product is. "No user serviceable parts inside"
> doesn't actually mean there isn't any parts you can't service yourself
> (there might or there might not be.) Rather, it means "We have not
> designed this product for you to service the parts yourself; so if you
> try, don't come crying to us if you break something."

The analogy doesn't hold in my opinion. The warning would have to be
"Don't use this equipment to do X and Y" to be analogous with the above
:-)

-- 
Preben Randhol -------------- http://www.pvv.org/~randhol/Ada95 --
                 �For me, Ada95 puts back the joy in programming.�

Re: ADA vs Java

[Preben Randhol]

On Tue, Jun 21, 2005 at 06:23:15PM +0200, Preben Randhol wrote:
> If Sun wanted to cover themselves legally they could have simply stated
> that you use the language and compiler at your own risk and that they
> cannot guarantee that the produced code is correct or acting as
> intended. The point that they especially writes that one should use it
                                                       ^^^^^^^^^^^^^^^^
OOPS: Should have been: one should NOT use it

> for situation X and Y means to me that they do think their product IS
> NOT suitable to be use in situation X and Y. 
> 
> My point is simply:
> 
> 1. They don't want people to use the compiler/language for X and Y
> 2. They don't want lawsuits due to bugs in compiler/language generally
-- 
Preben Randhol -------------- http://www.pvv.org/~randhol/Ada95 --
                 �For me, Ada95 puts back the joy in programming.�

Re: ADA vs Java

[Pascal Obry]

HansF <News.Hans@telus.net> writes:

> The question was originaly rhetorical - you claimed earlier that the
> standard disclaimer was related to safety and reliability, and now you
> acknowledge that Ada has bugs (at least potentially), but does not have a
> disclaimer, and therefore does not make the user aware of *possible*

No you missed an important point in one of my previous message. In Ada, for
safety critical softwares, one will use a certified runtime or no runtime at
all. Also in safety critical applications only a subset of Ada is used (there
is an annex for this and compiler are required to check that such or such
feature is not used). See also the SPARK-Ada subset.

Of course a compiler bug can still exists and show up in your code. Here
testing/validation/proof are important.

Note that I'm not on the safety-critical field, so I hope I did not say
something wrong :) Others will correct me anyway.

Pascal.

-- 

--|------------------------------------------------------
--| Pascal Obry                           Team-Ada Member
--| 45, rue Gabriel Peri - 78114 Magny Les Hameaux FRANCE
--|------------------------------------------------------
--|              http://www.obry.net
--| "The best way to travel is by means of imagination"
--|
--| gpg --keyserver wwwkeys.pgp.net --recv-key C1082595

Re: ADA vs Java

[HansF]

On Tue, 21 Jun 2005 18:48:05 +0200, Pascal Obry interested us by writing:

> 
> 
> No you missed an important point in one of my previous message. In Ada, for

Didn't miss it.  You apparently missed my points though.

> safety critical softwares, one will use a certified runtime or no runtime at
> all. Also in safety critical applications only a subset of Ada is used (there

Q: So, why would a person not use the full Ada in a safety critical
application?  

A? I assume that some document makes a statement like 'only the following
features/environment/capabilities/constructs/whatever are approved for
safety critical applications'.  

If true, that imposes limits and is equivalent to a disclaimer about using
the full capability of Ada in such environments - just not written by
lawyers.

(We've used up way too much bandwidth in this non-Ada group.  Final
word is yours - I hereby refrain from further responses.)

-- 
Hans Forbrich

Re: ADA vs Java

[Preben Randhol]

On Tue, Jun 21, 2005 at 05:08:21PM +0000, HansF wrote:
> Q: So, why would a person not use the full Ada in a safety critical
> application?  

Because you cannot manage to certify full Ada, C++, Java or even full C.
As Robert Dewar put it: "They have too much junk in them" (see the
lectures here: http://www.gnat.com/aa_lectures.php, as for the comment
it is at the end of the last video.)

-- 
Preben Randhol -------------- http://www.pvv.org/~randhol/Ada95 --
                 �For me, Ada95 puts back the joy in programming.�

Re: ADA vs Java

[Preben Randhol]

On Tue, Jun 21, 2005 at 07:15:49PM +0200, Preben Randhol wrote:
> On Tue, Jun 21, 2005 at 05:08:21PM +0000, HansF wrote:
> > Q: So, why would a person not use the full Ada in a safety critical
> > application?  
> 
> Because you cannot manage to certify full Ada, C++, Java or even full C.
> As Robert Dewar put it: "They have too much junk in them" (see the
> lectures here: http://www.gnat.com/aa_lectures.php, as for the comment
> it is at the end of the last video.)

And the SPARKAda link is: http://www.praxis-his.com/sparkada/intro.asp

-- 
Preben Randhol -------------- http://www.pvv.org/~randhol/Ada95 --
                 �For me, Ada95 puts back the joy in programming.�

Re: ADA vs Java

[Pascal Obry]

HansF <News.Hans@telus.net> writes:

> Q: So, why would a person not use the full Ada in a safety critical
> application?  

But this is not a constraint imposed by the Ada vendors. Nobody on earth (I
hope so at least) will use full Ada when it comes to human-lives as there is
too many constructs that can't be verified/certified. At least that's what I
like to think when I'm flying in an Air plane :)

Pascal.

-- 

--|------------------------------------------------------
--| Pascal Obry                           Team-Ada Member
--| 45, rue Gabriel Peri - 78114 Magny Les Hameaux FRANCE
--|------------------------------------------------------
--|              http://www.obry.net
--| "The best way to travel is by means of imagination"
--|
--| gpg --keyserver wwwkeys.pgp.net --recv-key C1082595

Re: Ada vs Java

[Björn Persson]

HansF wrote:
> [...] and now you
> acknowledge that Ada has bugs (at least potentially), but does not have a
> disclaimer, and therefore does not make the user aware of *possible*
> deficiencies. I see the potential for a lawsuit in any decently litigious
> society.

In that case I'm pretty sure the United States of America is the one and 
only "decently litigious" society on this planet.

Do you really, honestly think there is *any* nuclear power plant 
*anywhere* on the Earth, where the programmers who wrote the software 
for it didn't already *know* that any program may have bugs?

"The lawnmower didn't have a warning label stating that I shouldn't use 
it to trim my moustache, so it's the manufacturer's fault that I had my 
nose cut off!"

-- 
Bj�rn Persson                              PGP key A88682FD
                    omb jor ers @sv ge.
                    r o.b n.p son eri nu

Re: Ada vs Java

[Dmitry A. Kazakov]

On Tue, 21 Jun 2005 22:59:27 GMT, Bj�rn Persson wrote:

> HansF wrote:
>> [...] and now you
>> acknowledge that Ada has bugs (at least potentially), but does not have a
>> disclaimer, and therefore does not make the user aware of *possible*
>> deficiencies. I see the potential for a lawsuit in any decently litigious
>> society.
> 
> In that case I'm pretty sure the United States of America is the one and 
> only "decently litigious" society on this planet.
> 
> Do you really, honestly think there is *any* nuclear power plant 
> *anywhere* on the Earth, where the programmers who wrote the software 
> for it didn't already *know* that any program may have bugs?

It's no matter whether a product has a defect or not. What matters is who
would take the responsibility for the consequences. I wouldn't for any
program written in Java if that should work in any hazardous to one's life
environment. Neither Sun seeks for such adventures for itself...

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de

Re: Ada vs Java

[HansF]

On Wed, 22 Jun 2005 09:38:25 +0200, Dmitry A. Kazakov interested us by
writing:

> What matters is who
> would take the responsibility for the consequences.

THANK YOU!

-- 
Hans Forbrich 

Re: ADA vs Java

[Preben Randhol]

On Sun, Jun 19, 2005 at 10:19:27PM +0000, HansF wrote:
> <opinion>
> In my opinion, based on my experience, Ada will tend to be used in a
> professional environment tht includes proper analysis, specification and
> testing. As such, the attitude in an Ada environment may be as much or
> more important to critical programming than the fact that it is a solid
> piece of technology.
> </opinion>

So what you are saying is that C++ is just as safe, but the users are
generally sloppy and don't care so much if their programs crash? How can
a language where you are dependant on a debugger be a good language?

-- 
Preben Randhol -------------- http://www.pvv.org/~randhol/Ada95 --
                 �For me, Ada95 puts back the joy in programming.�

Re: ADA vs Java

[David Alex Lamb]

In article <bllse.12013$q46.11010@newsfe1-win.ntli.net>,
Ted <noaddress@fuspammer.com> wrote:
>Writing code in ADA 95 and compiling it for the JVM should produce more
>reliable code than writing in Java 2. Does anyone know any good technical
>reasons for prefering Java?

Last time I looked at Ada, its concurrency model was very different from the
threads Java uses.  Are you sure the JVM can handle all of Ada?
-- 
"Yo' ideas need to be thinked befo' they are say'd" - Ian Lamb, age 3.5
http://www.cs.queensu.ca/~dalamb/   qucis->cs to reply (it's a long story...)

Re: ADA vs Java

[HansF]

On Thu, 16 Jun 2005 20:32:07 +0000, Ted interested us by writing:

> Writing code in ADA 95 and compiling it for the JVM should produce more
> reliable code than writing in Java 2. Does anyone know any good technical
> reasons for prefering Java?

Both sides of the argument briefly discussed here:

	http://www.dwheeler.com/lovelace/s16sf.htm

Mind you, the site that page is on has a number of higher lavel pages
written in 1996-1998.  Things may have changed somewhat.

Also - looking at the site http://www.adahome.com/, which purports to be
the 'Home of Ada', page for one of the two Ada J-class generators listed
in the Resources provides a wonder 404, the other still doesn't load
(mind you - I use FireFox.)

So the technical reason might be "Cause it don't exist" ??? 

-- 
Hans Forbrich                           

Re: ADA vs Java

[Mark Lorenzen]

HansF <News.Hans@telus.net> writes:

> Also - looking at the site http://www.adahome.com/, which purports to be
> the 'Home of Ada', page for one of the two Ada J-class generators listed
> in the Resources provides a wonder 404, the other still doesn't load
> (mind you - I use FireFox.)

Don't look at www.adahome.com - it hasn't been maintained for a very,
very, long time. Try www.adapower.com instead.

- Mark Lorenzen

Re: ADA vs Java

[HansF]

On Fri, 17 Jun 2005 00:44:29 +0200, Mark Lorenzen interested us by
writing:

> Don't look at www.adahome.com - it hasn't been maintained for a very,
> very, long time.

I noticed <g>

Re: ADA vs Java

[Georg Bauhaus]

HansF wrote:
> On Thu, 16 Jun 2005 20:32:07 +0000, Ted interested us by writing:
> 
> 
>>Writing code in ADA 95 and compiling it for the JVM 
> 
> So the technical reason might be "Cause it don't exist" ??? 

Two compiler shops have Ada compilers targetting a JVM,
so you might ask them (AdaCore, Aonix). There is also a paper by
Tucker Taft explaining how and where Ada and a JVM are a good match.
It's called Programming the Internet in Ada 95, IIRC. It may
be a bit hard to find online at the moment.

Another article is here:
http://libre.act-europe.fr/papers/ada-on-jvm.pdf


-- Georg Bauhaus 

Re: ADA vs Java

[Preben Randhol]

On Fri, Jun 17, 2005 at 01:26:44AM +0200, Georg Bauhaus wrote:
> Two compiler shops have Ada compilers targetting a JVM,
> so you might ask them (AdaCore, Aonix). There is also a paper by
> Tucker Taft explaining how and where Ada and a JVM are a good match.
> It's called Programming the Internet in Ada 95, IIRC. It may
> be a bit hard to find online at the moment.

http://citeseer.ist.psu.edu/396935.html

-- 
Preben Randhol -------------- http://www.pvv.org/~randhol/Ada95 --
                 �For me, Ada95 puts back the joy in programming.�

Re: ADA vs Java

[Björn Persson]

HansF wrote:
> Also - looking at the site http://www.adahome.com/, which purports to be
> the 'Home of Ada', page for one of the two Ada J-class generators listed
> in the Resources provides a wonder 404, the other still doesn't load
> (mind you - I use FireFox.)
> 
> So the technical reason might be "Cause it don't exist" ??? 

Adahome.com is sadly out of date. Those who want information about Ada 
can start at http://adaworld.com/ or http://adapower.com/.

As for compiling Ada to Java byte code there is always Jgnat from 
AdaCore (ftp://cs.nyu.edu/pub/gnat/jgnat/), but it's not being 
maintained. As I understand it there wasn't enough interest. Apparently 
Ada programmers prefer compiling to machine code.

-- 
Bj�rn Persson                              PGP key A88682FD
                    omb jor ers @sv ge.
                    r o.b n.p son eri nu

Re: ADA vs Java

[The Wogster]

Ted wrote:
> Writing code in ADA 95 and compiling it for the JVM should produce more
> reliable code than writing in Java 2. Does anyone know any good technical
> reasons for prefering Java?
> 

The argument is more like, which language has a more reliable 
conversation, French or German?  Well people have been having 
conversations in both, for hundreds of years.

For reliability, a far more important aspect is the experience of the 
one who is writing the code, and what is their background.

Back to our human languages for a minute, suppose you know neither one, 
if you know Spanish or Italian then you will probably have more luck 
with French as they are all based on Latin.  If you have Austrian or to 
a lesser degree Dutch, many words and phrases are similar to German, so 
you will probably have more luck with it.

If your background in programming is C or C++, you will have better luck 
with Java, as many things are very similar.  If you come from a Pascal 
background you probably would find Ada easier.  No programming language 
is 100% safe, although some like C will provide you enough rope to hang 
yourself -- realistically C will provide the rope, tree, support, 
minister, and a handy helper, but that is beside the point.

The biggest issues with reliability are type safety and memory sanity 
checking.  Both languages take care of these reasonably well.

The problem for Ada is that most modern operating systems are written in 
C and documented in a C style, so most programming students learn C or 
C++ if nothing else.  Mind you, I still think that Pascal is probably 
the best teaching language for the basics......

W

Re: ADA vs Java

[Preben Randhol]

The Wogster <wogsterca@yahoo.ca> wrote on 17/06/2005 (13:26) :
> If your background in programming is C or C++, you will have better luck 
> with Java, as many things are very similar.  

I disagree. Just because the syntax is similar does not mean that you
will produce higher quality code. In the case of C I would say that it
is better to get used to a different way of thinking than the C way to
improve the quality.


Preben

Re: ADA vs Java

[Martin Dowie]

The Wogster wrote:
> If your background in programming is C or C++, you will have better luck 
> with Java, as many things are very similar.  If you come from a Pascal 
> background you probably would find Ada easier.

I find that Java has C/C++ syntax but is much, much closer to Ada for 
its semantics.

Cheers

-- Martin

Re: ADA vs Java

[Dale King]

The Wogster wrote:
> Ted wrote:
> 
>> Writing code in ADA 95 and compiling it for the JVM should produce more
>> reliable code than writing in Java 2. Does anyone know any good technical
>> reasons for prefering Java?
>>
> 
> The argument is more like, which language has a more reliable 
> conversation, French or German?  Well people have been having 
> conversations in both, for hundreds of years.

Interesting analogy, but it misses the important detail of the compiler. 
In your analogy of human language it would be like having a proofreader 
of what you were saying in the languages. In one case the proofreader is 
much better than the other being much more strict about grammar, making 
sure that you didn't have run-on sentences and passive voice.

Ada is a much stricter compiler and has much stronger typing (realizing 
that term means different things to different people). My experience 
using a similar type of language (Modula-2) is that it is harder to get 
things to compile because the "proofreader" keeps correcting your sloppy 
expressions and bad grammar, but when it did compile it was much more 
likely to be correct when executed.

The problem with translating Ada or other languages to Java is that the 
JVM lacks certain constructs that are part of other languages. The 
simplest example would be that Java lacks unsigned numerical types in a 
size other than 16 bits.

-- 
  Dale King

Re: ADA vs Java

[Ted]

"Dale King" <DaleWKing@insightbb.nospam.com> wrote in message
news:8_Kse.61630$_o.33510@attbi_s71...
> The Wogster wrote:
> > Ted wrote:
> >
> >> Writing code in ADA 95 and compiling it for the JVM should produce more
> >> reliable code than writing in Java 2. Does anyone know any good
technical
> >> reasons for prefering Java?
> >>
> >
> Ada is a much stricter compiler and has much stronger typing ....it is
harder to get
> things to compile ... but when it did compile it was much more
> likely to be correct when executed.
>
> The problem with translating Ada or other languages to Java is that the
> JVM lacks certain constructs that are part of other languages. The
> simplest example would be that Java lacks unsigned numerical types in a
> size other than 16 bits.
>

OK,  the JVM has certain limitations one would have to restrict oneself to a
subset of ADA. Wouldn't ADA code still be moire reliable than code written
in Java 2?

Re: ADA vs Java

[Steve]

"The Wogster" <wogsterca@yahoo.ca> wrote in message 
news:KYzse.7874$yU.711331@news20.bellglobal.com...
> Ted wrote:
>> Writing code in ADA 95 and compiling it for the JVM should produce more
>> reliable code than writing in Java 2. Does anyone know any good technical
>> reasons for prefering Java?
>>
>
> The argument is more like, which language has a more reliable 
> conversation, French or German?  Well people have been having 
> conversations in both, for hundreds of years.
>
> For reliability, a far more important aspect is the experience of the one 
> who is writing the code, and what is their background.
>

So, if I understand what you're saying.  There is no point in developing any 
new tools for sofware development that make programming more efficient or 
reduce defects, because none of that really matters... It is just 
programming tools, and they have been around for decades.

I spend a lot of time keeping track of the new tools that become available. 
I learn advantages and disadvantages of new tools and techniques.  I guess I 
have been wasting my time.

I learned BASIC, FORTRAN, Pascal, and COBOL in school.  I guess I was 
wasting my time when I learned C, C++, Ada, C#, Modula-2, Java, and FORTH.

Realistically, I think it makes sense to do objective research on the use of 
different programming languages, productivity, and defect rates.  It is 
unfortunate that people often disregard the results if such research and say 
"it really doesn't matter... it's just preferance".  Or it's just like 
comparing French and German.

Steve
(The Duck)

>
> W 

small plug for #ada iirc channel

[Rod Kay]

Hello,

    I found the #ada channel lately and am a little surprised how little the 
Ada community make use of what I have found to be an invaluable resource.

    I'm beginning to suspect that the channel op is in fact an Ada 'bot' ... 
able to point you towards an Ada solution for most problems, and quoting the 
LRM chapter & verse.

    If the channel op is not available (infrequent) there is generally someone 
else about to help ...

    So, in short, if you have an Ada prob and need a quick answer, try #ada. 
Students, hobbyists and those new to Ada, in particular, may find the channel 
helpful.


regards,

Rod.


ps: Of course, it may well be that Ada is so simple and elegant, that help is 
little needed ... ;).

Re: small plug for #ada iirc channel

[Alex R. Mosteo]

Rod Kay wrote:
> Hello,
> 
>     I found the #ada channel lately and am a little surprised how little the 
> Ada community make use of what I have found to be an invaluable resource.

In which network is it located?

> 
>     I'm beginning to suspect that the channel op is in fact an Ada 'bot' ... 
> able to point you towards an Ada solution for most problems, and quoting the 
> LRM chapter & verse.
> 
>     If the channel op is not available (infrequent) there is generally someone 
> else about to help ...
> 
>     So, in short, if you have an Ada prob and need a quick answer, try #ada. 
> Students, hobbyists and those new to Ada, in particular, may find the channel 
> helpful.
> 
> 
> regards,
> 
> Rod.
> 
> 
> ps: Of course, it may well be that Ada is so simple and elegant, that help is 
> little needed ... ;).

Re: small plug for #ada iirc channel

[Alex R. Mosteo]

Alex R. Mosteo wrote:
> Rod Kay wrote:
> 
>> Hello,
>>
>>     I found the #ada channel lately and am a little surprised how 
>> little the Ada community make use of what I have found to be an 
>> invaluable resource.
> 
> 
> In which network is it located?

Sorry, already answered.

Re: small plug for #ada iirc channel

[Preben Randhol]

On Sat, Jun 18, 2005 at 03:44:12PM +1000, Rod Kay wrote:
> 
> Hello,
> 
>     I found the #ada channel lately and am a little surprised how little the 
> Ada community make use of what I have found to be an invaluable resource.

Didn't know of this. Which server?

-- 
Preben Randhol -------------- http://www.pvv.org/~randhol/Ada95 --
                 �For me, Ada95 puts back the joy in programming.�

Re: small plug for #ada iirc channel

[Rod Kay]

On Sat, 18 Jun 2005 04:14 pm, Preben Randhol wrote:
> On Sat, Jun 18, 2005 at 03:44:12PM +1000, Rod Kay wrote:
> > Hello,
> >
> >     I found the #ada channel lately and am a little surprised how little
> > the Ada community make use of what I have found to be an invaluable
> > resource.
>
> Didn't know of this. Which server?

    I use the 'Freenode' server at 'irc.au.freenode.net'.