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Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;)

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  Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-17 15:09 +0200
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-17 09:23 -0400
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-17 17:26 +0200
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Heikki Kallasjoki <fis+usenet@zem.fi> - 2012-05-17 16:19 +0000
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-17 19:57 +0200
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2012-05-17 18:33 +0000
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-17 23:25 +0200
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <lewbloch@gmail.com> - 2012-05-17 14:52 -0700
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-05-17 14:58 -0700
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-17 17:59 -0400
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Heikki Kallasjoki <fis+usenet@zem.fi> - 2012-05-17 22:13 +0000
                  Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-18 01:18 +0200
                    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-17 21:32 -0400
                      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Noob <root@127.0.0.1> - 2012-05-18 17:08 +0200
                        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-19 20:53 +0200
                        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-19 21:19 +0200
                          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-05-19 18:47 -0700
                            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-20 17:55 +0200
                      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-19 20:18 +0200
                        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-19 20:21 +0200
                          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-19 20:52 +0200
                          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:27 -0400
                        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <noone@lewscanon.com> - 2012-05-19 14:48 -0700
                          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <noone@lewscanon.com> - 2012-05-19 15:20 -0700
                            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <noone@lewscanon.com> - 2012-05-19 15:35 -0700
                        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:25 -0400
                        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) bugbear <bugbear@trim_papermule.co.uk_trim> - 2012-05-21 17:12 +0100
                    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Heikki Kallasjoki <fis+usenet@zem.fi> - 2012-05-18 07:22 +0000
                    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <noone@lewscanon.com> - 2012-05-19 14:50 -0700
                    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:21 -0400
                    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:23 -0400
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-18 01:09 +0200
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:14 -0400
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 09:36 +0200
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-20 17:53 +0200
              Re: names for parameters of ranges Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:30 -0400
                Re: names for parameters of ranges Gene Wirchenko <genew@ocis.net> - 2012-05-20 20:48 -0700
              Re: names for parameters of ranges (was: ...) Willem <willem@toad.stack.nl> - 2012-05-23 09:43 +0000
                Re: names for parameters of ranges Willem <willem@toad.stack.nl> - 2012-05-23 11:07 +0000
                  Re: names for parameters of ranges Willem <willem@toad.stack.nl> - 2012-05-23 15:42 +0000
                Re: names for parameters of ranges Willem <willem@toad.stack.nl> - 2012-05-23 11:11 +0000
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Heikki Kallasjoki <fis+usenet@zem.fi> - 2012-05-17 19:13 +0000
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Heikki Kallasjoki <fis+usenet@zem.fi> - 2012-05-17 19:19 +0000
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Jim Janney <jjanney@shell.xmission.com> - 2012-05-17 18:35 -0600
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-17 23:16 +0200
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:32 -0400
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 09:40 +0200
                  Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-21 10:05 -0400
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 14:41 -0400
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:12 -0400
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Keith Thompson <kst-u@mib.org> - 2012-05-20 16:38 -0700
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <noone@lewscanon.com> - 2012-05-20 18:52 -0700
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Keith Thompson <kst-u@mib.org> - 2012-05-20 19:21 -0700
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) gazelle@shell.xmission.com (Kenny McCormack) - 2012-05-21 08:24 +0000
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Bill Leary" <Bill_Leary@msn.com> - 2012-05-23 14:34 -0400
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2012-05-20 21:46 -0600
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <noone@lewscanon.com> - 2012-05-21 00:04 -0700
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) gazelle@shell.xmission.com (Kenny McCormack) - 2012-05-21 08:25 +0000
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 09:46 +0200
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) jacob navia <jacob@spamsink.net> - 2012-05-17 18:54 +0200
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Mark Storkamp <mstorkamp@yahoo.com> - 2012-05-17 12:06 -0500
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) markspace <-@.> - 2012-05-17 10:11 -0700
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <lewbloch@gmail.com> - 2012-05-17 14:43 -0700
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) markspace <-@.> - 2012-05-17 16:13 -0700
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) markspace <-@.> - 2012-05-17 16:42 -0700
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Jan Burse <janburse@fastmail.fm> - 2012-05-18 02:27 +0200
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 15:06 -0400
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Marius" <sorry@nospamfor.me> - 2012-05-17 17:32 +0000
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-17 23:45 +0200
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Marius" <sorry@nospamfor.me> - 2012-05-17 22:16 +0000
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-18 00:47 +0200
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-24 14:11 +0200
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-24 14:17 +0200
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Roedy Green <see_website@mindprod.com.invalid> - 2012-05-18 02:57 -0700
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Leif Roar Moldskred <leifm@dimnakorr.com> - 2012-05-18 05:26 -0500
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-18 08:08 -0400
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 14:46 -0400
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) rossum <rossum48@coldmail.com> - 2012-05-18 12:25 +0100
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Gene Wirchenko <genew@ocis.net> - 2012-05-18 10:46 -0700
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-19 21:01 +0200
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:33 -0400
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Patricia Shanahan <pats@acm.org> - 2012-05-20 16:30 -0700
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Gene Wirchenko <genew@ocis.net> - 2012-05-20 20:36 -0700
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Kaz Kylheku <kaz@kylheku.com> - 2012-05-21 04:28 +0000
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 09:55 +0200
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 09:49 +0200
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-21 10:08 -0400
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 10:45 +0200
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 11:13 +0200
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 11:19 +0200
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <lewbloch@gmail.com> - 2012-05-21 11:40 -0700
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:10 -0400
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 10:00 +0200
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-21 10:10 -0400
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) falk@rahul.net (Edward A. Falk) - 2012-05-23 05:40 +0000
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Jim Janney <jjanney@shell.xmission.com> - 2012-05-23 08:46 -0600
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-24 14:03 +0200
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <lewbloch@gmail.com> - 2012-05-24 09:56 -0700
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) falk@rahul.net (Edward A. Falk) - 2012-05-26 00:52 +0000
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Jamie <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> - 2012-05-25 21:16 -0400
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Kevin McMurtrie <mcmurtrie@pixelmemory.us> - 2012-05-24 09:42 -0700

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#14576 — Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;)

Hello,

My hypothesis that a human being cannot write 10 lines of code without 
making a mistake has been confirmed by either oracle or google or both 
depending on what you believe ;)

The lawsuit apperently mentions these 9 lines of code:

"
private static void rangeCheck(int arrayLen, int fromIndex, int toIndex) {
    if (fromIndex > toIndex)
        throw new IllegalArgumentException("fromIndex(" + fromIndex +
                   ") > toIndex(" + toIndex+")");
    if (fromIndex < 0)
        throw new ArrayIndexOutOfBoundsException(fromIndex);
    if (toIndex > arrayLen)
        throw new ArrayIndexOutOfBoundsException(toIndex);
}
"

There is at least 1 major bug in it:

toIndex could equal arrayLen which would still be out of bounds assuming 
zero-index-based arrays.

So for example if the array length is 100, then toIndex is valid for range 0 
to 99.

And therefore the exception should be raised for equalness to arrayLen as 
well.

So the correct code should probably have been ">=" instead of just ">".

Except if some special outside code assumes that it's ok... I don't know 
where this routine is being used... but by itself it would be flawed.

Also fromIndex could also still go out of range past arrayLen this is also 
not checked.

So this code seems highly buggy and does somewhat prove that it was copied 
?!

It's a bit unlikely that two programmers make the exact same dumb mistake ! 
;)

So the funny part is, the bugs in it kinda prove that it was copied ! ;)

Mimimimimimimmimimi :)

Bye,
  Skybuck.

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#14577

On 5/17/2012 9:09 AM, Skybuck Flying wrote:
> There is at least 1 major bug in it:
>
> toIndex could equal arrayLen which would still be out of bounds assuming
> zero-index-based arrays.

I believe toIndex in this case is being used in half-open notation, so 
toIndex is the first element not accessed.

-- 
Beware of bugs in the above code; I have only proved it correct, not 
tried it. -- Donald E. Knuth

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#14578

"Fred K"  wrote in message 
news:29308868.1994.1337265697084.JavaMail.geo-discussion-forums@pbcuc6...

On Thursday, May 17, 2012 6:09:23 AM UTC-7, Skybuck Flying wrote:
> Hello,
>
> My hypothesis that a human being cannot write 10 lines of code without
> making a mistake has been confirmed by either oracle or google or both
> depending on what you believe ;)
>
> The lawsuit apperently mentions these 9 lines of code:
>
> "
> private static void rangeCheck(int arrayLen, int fromIndex, int toIndex) {
>     if (fromIndex > toIndex)
>         throw new IllegalArgumentException("fromIndex(" + fromIndex +
>                    ") > toIndex(" + toIndex+")");

"
This is not C.
"

It's a curly brace language which the same kind of stupid c programming see 
below.

>     if (fromIndex < 0)
>         throw new ArrayIndexOutOfBoundsException(fromIndex);
>     if (toIndex > arrayLen)
>         throw new ArrayIndexOutOfBoundsException(toIndex);
> }
> "
>
> There is at least 1 major bug in it:
>
> toIndex could equal arrayLen which would still be out of bounds assuming
> zero-index-based arrays.
>
> So for example if the array length is 100, then toIndex is valid for range 
> 0
> to 99.
>
> And therefore the exception should be raised for equalness to arrayLen as
> well.
>
> So the correct code should probably have been ">=" instead of just ">".
>
> Except if some special outside code assumes that it's ok... I don't know
> where this routine is being used... but by itself it would be flawed.
>
> Also fromIndex could also still go out of range past arrayLen this is also
> not checked.
>

"
Actually it is checked by the combined actions of the first and third "if" 
statements.
"

A very perverse way. The mission is to check if indexes are outside the 
array "out of bounds".

Furthermore it makes no sense, copieing from high to low should be possible 
as well, so it's obvious this code assumes that copieing from low to high is 
the only possibility. A strange assumption to make, making this code much 
less usuable and much less flexible in the case it needs to be adjusted to 
accommodate for this new functionality as will often be the case with 
software and changing requirements.

Furthermore it seems to be an "optimization". Instead of simple using 4 
branches, the code tries to do it with 3.

Furthermore a dependency is added on the correctness of another branch. 
Since the 3 branch is incorrect the first one is now incorrect as well 
leading to two different possible bugs instead of just one.

bug1: toIndex can now be out of bounds.

bug2: fromIndex can now be out of bounds as well.

Example: 100 100

This code is a nice example oh how not to program.

Apperently only a skilled coder/debugger like me seems to be able to spot 
the fallacies in this way too debug-complex code.

Lesson to be learned from this code:

Do not introduce dependencies like this.

> So this code seems highly buggy and does somewhat prove that it was copied
> ?!
>
> It's a bit unlikely that two programmers make the exact same dumb mistake 
> !
> ;)
>
> So the funny part is, the bugs in it kinda prove that it was copied ! ;)
>
> Mimimimimimimmimimi :)

Bye,
  Skybuck. 

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#14582

On 2012-05-17, Skybuck Flying <Windows7IsOK@DreamPC2006.com> wrote:
>> private static void rangeCheck(int arrayLen, int fromIndex, int toIndex) {
>>     if (fromIndex > toIndex)
>>         throw new IllegalArgumentException("fromIndex(" + fromIndex +
>>                    ") > toIndex(" + toIndex+")");
>>     if (fromIndex < 0)
>>         throw new ArrayIndexOutOfBoundsException(fromIndex);
>>     if (toIndex > arrayLen)
>>         throw new ArrayIndexOutOfBoundsException(toIndex);
>> }

> A very perverse way. The mission is to check if indexes are outside the 
> array "out of bounds".
>
> Furthermore it makes no sense, copieing from high to low should be possible 

Who said anything about copying?

I believe it is checking whether the range fromIndex, fromIndex+1, ...,
toIndex-1 -- i.e., a range given as the first index and one past the
last index, not an uncommon practice -- is within the array, in which
case it has no bugs.  (toIndex may legally equal the length of the array
when the range extends to the last element, and requiring the range to
be specified "the right way around" is not especially perverse.)


-- 
Heikki Kallasjoki

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#14588

"Heikki Kallasjoki"  wrote in message news:slrnjra97k.d62.fis@iris.zem.fi...

On 2012-05-17, Skybuck Flying <Windows7IsOK@DreamPC2006.com> wrote:
>> private static void rangeCheck(int arrayLen, int fromIndex, int toIndex) 
>> {
>>     if (fromIndex > toIndex)
>>         throw new IllegalArgumentException("fromIndex(" + fromIndex +
>>                    ") > toIndex(" + toIndex+")");
>>     if (fromIndex < 0)
>>         throw new ArrayIndexOutOfBoundsException(fromIndex);
>>     if (toIndex > arrayLen)
>>         throw new ArrayIndexOutOfBoundsException(toIndex);
>> }

> A very perverse way. The mission is to check if indexes are outside the
> array "out of bounds".
>
> Furthermore it makes no sense, copieing from high to low should be 
> possible

"
Who said anything about copying?
"

It seems likely this code is called right before the array is accessed to 
try and prevent an access violation, instead it tries to throw a somewhat 
nicer exception message to indicate a problem with array access.

(Reading/writing to an array can be considered "copieing").

"
I believe it is checking whether the range fromIndex, fromIndex+1, ...,
toIndex-1 -- i.e., a range given as the first index and one past the
last index, not an uncommon practice -- is within the array, in which
case it has no bugs.  (toIndex may legally equal the length of the array
when the range extends to the last element, and requiring the range to
be specified "the right way around" is not especially perverse.)
"

It's simply not valid. Out of bounds has a very clear meaning in programming 
practice. It's either within bounds or it's not. The bounds of a java array 
are very clearly defined. Thus the only logical conclusion is that the code 
is simply bugged.
Either in logic or in description. Either change the exception-description 
or fix the code.

If this were some stack based structure then it would make sense that the 
index could go one beyond the size. However it's not a stack, but an array.

The perversity is not with checking if "to" is beyond "from". The perversity 
is the logical dependency of the "from" out of bounds check onto the "to" 
out of bounds check.

Both indexes can be considered separate indexes and there a simply routine 
which would check each index individually would be better/preferred.

However this routine seems to try and do multiple tasks all at once, which 
is another bad coding practice.

Therefore advice:

1. Split routine up into two separate routines:

First routine to check if a single index is out of bounds.

Second routine to check if the indexes are in proper order.

Further more checking the indexes independently might even execute faster 
because of instruction level parallelism, so this attempted optimization 
might actually be counter productive, except for perhaps less instruction 
decoding.

The call overhead of using multiple routines could be counter acted by 
inlining features. I am not sure if java has "inlining" support.

Bye,
  Skybuck.

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#14589

In comp.lang.java.programmer Skybuck Flying <Windows7IsOK@dreampc2006.com> wrote:

(snip)

>>>     if (fromIndex < 0)
>>>         throw new ArrayIndexOutOfBoundsException(fromIndex);
>>>     if (toIndex > arrayLen)
>>>         throw new ArrayIndexOutOfBoundsException(toIndex);


(snip, someone else wrote)

>> I believe it is checking whether the range fromIndex, fromIndex+1, ...,
>> toIndex-1 -- i.e., a range given as the first index and one past the
>> last index, not an uncommon practice -- is within the array, in which
>> case it has no bugs.  (toIndex may legally equal the length of the array
>> when the range extends to the last element, and requiring the range to
>> be specified "the right way around" is not especially perverse.)
>> "

> It's simply not valid. Out of bounds has a very clear meaning 
> in programming practice. It's either within bounds or it's not. 

But this isn't "programming" it is Java, and Java can do it however
it wants to.

> The bounds of a java array are very clearly defined. Thus the 
> only logical conclusion is that the code is simply bugged.  
> Either in logic or in description. Either change the 
> exception-description or fix the code.

Look at the definition of the substring method in String class.

It avoids a lot of -1 by the programmer to define it this way.
(Along with consistently starting indexing at zero.)

-- glen

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#14594

"
"glen herrmannsfeldt"  wrote in message 
news:jp3g9r$v22$1@speranza.aioe.org...

In comp.lang.java.programmer Skybuck Flying <Windows7IsOK@dreampc2006.com> 
wrote:

(snip)

>>>     if (fromIndex < 0)
>>>         throw new ArrayIndexOutOfBoundsException(fromIndex);
>>>     if (toIndex > arrayLen)
>>>         throw new ArrayIndexOutOfBoundsException(toIndex);


(snip, someone else wrote)

>> I believe it is checking whether the range fromIndex, fromIndex+1, ...,
>> toIndex-1 -- i.e., a range given as the first index and one past the
>> last index, not an uncommon practice -- is within the array, in which
>> case it has no bugs.  (toIndex may legally equal the length of the array
>> when the range extends to the last element, and requiring the range to
>> be specified "the right way around" is not especially perverse.)
>> "

> It's simply not valid. Out of bounds has a very clear meaning
> in programming practice. It's either within bounds or it's not.


But this isn't "programming" it is Java, and Java can do it however
it wants to.

> The bounds of a java array are very clearly defined. Thus the
> only logical conclusion is that the code is simply bugged.
> Either in logic or in description. Either change the
> exception-description or fix the code.

Look at the definition of the substring method in String class.

It avoids a lot of -1 by the programmer to define it this way.
(Along with consistently starting indexing at zero.)
"

Not really,

Programmers of all languages must be able to communicate with each other 
through common language and concepts.

One such concept is "range".

It's pretty clearly defined:

http://en.wikipedia.org/wiki/Range_(computer_programming)

Any computer language deviating from the standard/common meaning of range 
should clearly state so.

Any code deviating from the standard/coming meaning of range should clearly 
state so.

Obviously if the routine was ment to check "range" then it's flawed.

Obviously if the routine was ment to check "range-1" then it’s name should 
have been slightly different to state just that, example:

checkRangeMinusOne

or

checkRangeInclusiveExclusive

or

CheckRangeExceptLast

Fortunately for us the code is available, but this is not always the case in 
other programming languages like C where sometimes only headers are 
available.

Nice way to sneak in bugs ! ;)

Bye,
  Skybuck. 

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#14598

Skybuck Flying wrote:
> Not really,
> 
> Programmers of all languages must be able to communicate with each other 
> through common language and concepts.
> 
> One such concept is "range".
> 
> It's pretty clearly defined:
> 
> http://en.wikipedia.org/wiki/Range_(computer_programming)

That definition does not contradict what others have said. 
For example, it clearly states that the range of an array in 
zero-index languages is from the lower bound (zero) to 
one less than the length of the array.

If the variables in the program you incorrectly deride 
specified the range differently from that, you would be right, 
but they don't, so you're wrong.

> Any computer language deviating from the standard/common meaning of range 
> should clearly state so.

Java is not such a language.

> Any code deviating from the standard/coming meaning of range should clearly 
> state so.

The code you cite does not so deviate.

> Obviously if the routine was ment to check "range" then it's flawed.

Obviously it is not. If you write a loop such as 

  for (int index = 0; index < TOP; ++index) { ... } 

it is perfectly legal for TOP to equal the array length, as in the 
code you excoriate. If you wish to check that "0" and "TOP" specify 
a valid range, you'd call that routine with 

  rangeCheck( array.length, 0, TOP);

just like they say to, and it would check the range just as defined 
in the Wikipedia article you cite.

Your logic is what's flawed.

I guess you aren't such a skilled "coder/debugger" as you claim.

> Obviously if the routine was ment to check "range-1" then it’s [sic]
> name should  have been slightly different to state just that, example:

Obviously that is just your own idiosyncratic style despotism speaking.

> 
> checkRangeMinusOne
> 
> or
> 
> checkRangeInclusiveExclusive
> 
> or
> 
> CheckRangeExceptLast
> 
> Fortunately for us the code is available, but this is not always the case in 
> other programming languages like C where sometimes only headers are 
> available.
> 
> Nice way to sneak in bugs ! ;)

You have shown no bugs.

You don't even cite how that routine is used, you only speculate
and rant based on your unfounded assumptions and reasoning.

-- 
Lew

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#14599

On 5/17/12 2:25 PM, Skybuck Flying wrote:
> But this isn't "programming" it is Java, and Java can do it however
> it wants to.
>
>> The bounds of a java array are very clearly defined. Thus the
>> only logical conclusion is that the code is simply bugged.
>> Either in logic or in description. Either change the
>> exception-description or fix the code.
>
> Look at the definition of the substring method in String class.
>
> It avoids a lot of -1 by the programmer to define it this way.
> (Along with consistently starting indexing at zero.)
> "
>
> Not really,
>
> Programmers of all languages must be able to communicate with each other
> through common language and concepts.
>
> One such concept is "range".
I read the method as saying "Verify this range is valid for this array 
length." and it is according to the algorithm used.

It is a programming concept, open ended ranges are very frequent.

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#14600

On 5/17/2012 5:25 PM, Skybuck Flying wrote:
> One such concept is "range".
>
> It's pretty clearly defined:
>
> http://en.wikipedia.org/wiki/Range_(computer_programming)
>
> Any computer language deviating from the standard/common meaning of
> range should clearly state so.

In 0-based array indexes, the standard interpretation of a range is the 
half-open model: start <= value < end. Note in particular things like 
the standard STL idioms, JavaScript slice, python's methods.

That you spend so much time arguing that this interpretation is wrong 
indicates that you don't both to do much programming. Also, note that 
Wikipedia isn't necessarily correct.

-- 
Beware of bugs in the above code; I have only proved it correct, not 
tried it. -- Donald E. Knuth

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#14602

On 2012-05-17, Joshua Cranmer <Pidgeot18@verizon.invalid> wrote:
> On 5/17/2012 5:25 PM, Skybuck Flying wrote:
>> One such concept is "range".
>>
>> It's pretty clearly defined:
>>
>> http://en.wikipedia.org/wiki/Range_(computer_programming)
>>
>> Any computer language deviating from the standard/common meaning of
>> range should clearly state so.
>
> In 0-based array indexes, the standard interpretation of a range is the 
> half-open model: start <= value < end. Note in particular things like 
> the standard STL idioms, JavaScript slice, python's methods.

And, most relevantly in this context, the standard methods in
java.util.Arrays (binarySearch, copyOfRange, fill, sort), all of which
accept ranges using the half-open "inclusive start, exclusive end" way.
Most of them even have parameters called "fromIndex" and "toIndex",
identically to rangeCheck.  Surely it would be strange and unexpected to
deviate from this "standard/common meaning" used by the system libraries.

(Not to mention that the code in question, in its generated-documentation
comments quoted elsethread, does clearly state what the arguments mean.)


-- 
Heikki Kallasjoki

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#14607

"Heikki Kallasjoki"  wrote in message news:slrnjrau0n.f5o.fis@iris.zem.fi...

On 2012-05-17, Joshua Cranmer <Pidgeot18@verizon.invalid> wrote:
> On 5/17/2012 5:25 PM, Skybuck Flying wrote:
>> One such concept is "range".
>>
>> It's pretty clearly defined:
>>
>> http://en.wikipedia.org/wiki/Range_(computer_programming)
>>
>> Any computer language deviating from the standard/common meaning of
>> range should clearly state so.
>
> In 0-based array indexes, the standard interpretation of a range is the
> half-open model: start <= value < end. Note in particular things like
> the standard STL idioms, JavaScript slice, python's methods.

"
And, most relevantly in this context, the standard methods in
java.util.Arrays (binarySearch, copyOfRange, fill, sort), all of which
accept ranges using the half-open "inclusive start, exclusive end" way.
Most of them even have parameters called "fromIndex" and "toIndex",
identically to rangeCheck.  Surely it would be strange and unexpected to
deviate from this "standard/common meaning" used by the system libraries.

(Not to mention that the code in question, in its generated-documentation
comments quoted elsethread, does clearly state what the arguments mean.)
"

There is no "rangeCheck" function for java.util.Arrays:

http://docs.oracle.com/javase/6/docs/api/java/util/Arrays.html

To me it appears as if rangeCheck is some low level operating system code or 
memory management code to try and prevent the os or applications from 
crashing or exploits from taking over the system.

It would be interesting to know where this "rangeCheck" function is from.

I would not be surprised that the functions you mentioned would be the cause 
of many bugs in java programs.

Almost seems like a deliberate design to make java programs crash... perhaps 
a nice test for the "sand boxing" which after many years has proven to be a 
failure, google for java exploits ;)

One of the reasons why java will not be installed onto my computers now and 
in the future.

Seeing these functions only re-assures me of my decision to do so.

Bye,
  Skybuck. 

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#14611

On 5/17/2012 7:18 PM, Skybuck Flying wrote:
> There is no "rangeCheck" function for java.util.Arrays:
>
> http://docs.oracle.com/javase/6/docs/api/java/util/Arrays.html
>
> To me it appears as if rangeCheck is some low level operating system
> code or memory management code to try and prevent the os or applications
> from crashing or exploits from taking over the system.

It's a private method in java.util.Arrays, which is why the API does not 
list it. If you actually read the code you'd posted, you would have 
realized that.

-- 
Beware of bugs in the above code; I have only proved it correct, not 
tried it. -- Donald E. Knuth

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#14619

Joshua Cranmer wrote:

> It's a private method in java.util.Arrays, which is why the API does
> not list it. If you actually read the code you'd posted, you would
> have realized that.

Dear Joshua,

Sane people have kill-filed "Skybuck Flying" so long ago that
they don't remember whether they used a computer or an abacus
to set up the kill file.

Regards.

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#14651

"Noob"  wrote in message news:jp5olq$bl2$1@dont-email.me... 

Joshua Cranmer wrote:

> It's a private method in java.util.Arrays, which is why the API does
> not list it. If you actually read the code you'd posted, you would
> have realized that.

"
Dear Joshua,

Sane people have kill-filed "Skybuck Flying" so long ago that
they don't remember whether they used a computer or an abacus
to set up the kill file.

Regards.
"

More trash from: A noiseless patient Spider

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#14661

"Noob"  wrote in message news:jp5olq$bl2$1@dont-email.me...

Joshua Cranmer wrote:

> It's a private method in java.util.Arrays, which is why the API does
> not list it. If you actually read the code you'd posted, you would
> have realized that.

"
Dear Joshua,

Sane people have kill-filed "Skybuck Flying" so long ago that
they don't remember whether they used a computer or an abacus
to set up the kill file.

Regards.
"

Can you please stop abusing my threads.

I think you are Jamie, I already asked you to stay out of my threads.

If you not Jamie, then I ask you as well, to stay out of my threads, because 
you are wasting my time.

I come here to discuss technical matters and not personal or even legal 
matters for that matter.

Bye,
  Skybuck. 

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#14664

On 5/19/12 12:19 PM, Skybuck Flying wrote:
>
>
> "Noob" wrote in message news:jp5olq$bl2$1@dont-email.me...
>
> Joshua Cranmer wrote:
>
>> It's a private method in java.util.Arrays, which is why the API does
>> not list it. If you actually read the code you'd posted, you would
>> have realized that.
>
> "
> Dear Joshua,
>
> Sane people have kill-filed "Skybuck Flying" so long ago that
> they don't remember whether they used a computer or an abacus
> to set up the kill file.
>
> Regards.
> "
>
> Can you please stop abusing my threads.
>
> I think you are Jamie, I already asked you to stay out of my threads.
>
> If you not Jamie, then I ask you as well, to stay out of my threads,
> because you are wasting my time.
>
> I come here to discuss technical matters and not personal or even legal
> matters for that matter.
>
> Bye,
> Skybuck.
Skybuck, seriously *you're* the one that abuses threads. Perhaps if you 
stopped and thought longer, you wouldn't need to reply to yourself 
multiple times.  Also, when most of the community expresses how you've 
misinterpreted something, it might be a signal that you actually are 
wrong. I know, strange that might happen, but sometimes it does.

Don't bother replying to this, I'm not interested in a troll fest.

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#14674

"Daniel Pitts"  wrote in message news:Q2Ytr.22260$TC4.21494@newsfe14.iad...

On 5/19/12 12:19 PM, Skybuck Flying wrote:
>
>
> "Noob" wrote in message news:jp5olq$bl2$1@dont-email.me...
>
> Joshua Cranmer wrote:
>
>> It's a private method in java.util.Arrays, which is why the API does
>> not list it. If you actually read the code you'd posted, you would
>> have realized that.
>
> "
> Dear Joshua,
>
> Sane people have kill-filed "Skybuck Flying" so long ago that
> they don't remember whether they used a computer or an abacus
> to set up the kill file.
>
> Regards.
> "
>
> Can you please stop abusing my threads.
>
> I think you are Jamie, I already asked you to stay out of my threads.
>
> If you not Jamie, then I ask you as well, to stay out of my threads,
> because you are wasting my time.
>
> I come here to discuss technical matters and not personal or even legal
> matters for that matter.
>
> Bye,
> Skybuck.

"
Skybuck, seriously *you're* the one that abuses threads. Perhaps if you
stopped and thought longer, you wouldn't need to reply to yourself
multiple times.  Also, when most of the community expresses how you've
misinterpreted something, it might be a signal that you actually are
wrong. I know, strange that might happen, but sometimes it does.

Don't bother replying to this, I'm not interested in a troll fest.
"

We were having a nice discussion, no need to start asking people to kill 
file me.

It was interesting/educational for everybody I think ! ;) =D

It has shed some led on short comings with java and c++ and ranges for some 
! ;)

Bye,
  Skybuck. 

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#14647

"Joshua Cranmer"  wrote in message news:jp48rq$6s8$1@dont-email.me...

On 5/17/2012 7:18 PM, Skybuck Flying wrote:
> There is no "rangeCheck" function for java.util.Arrays:
>
> http://docs.oracle.com/javase/6/docs/api/java/util/Arrays.html
>
> To me it appears as if rangeCheck is some low level operating system
> code or memory management code to try and prevent the os or applications
> from crashing or exploits from taking over the system.

"
It's a private method in java.util.Arrays, which is why the API does not
list it. If you actually read the code you'd posted, you would have
realized that.
"

Nonsense, this code could have come from anywhere.

There is no proof that this came from any api at all.

I have yet to see any proof from the court case that this is actually from 
java.util.Arrays.

The only thing hinting that it might be a private method is the static 
keyword, well excuse me for not being a java expert ;)

Bye,
  Skybuck.

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#14648

Anyway the court case seems to be about "copyrightable api".

If this is actually a private method then I don't see how that's relevant... 
since it's not part of the actually published api ! ;)

Bye,
  Skybuck. 

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