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Groups > comp.lang.java.programmer > #18474
| From | Jim Janney <jjanney@shell.xmission.com> |
|---|---|
| Newsgroups | comp.lang.java.programmer |
| Subject | Re: hashCode |
| Date | 2012-08-31 09:08 -0600 |
| Organization | Pan-Pacific Grand Prix |
| Message-ID | <ydn1uint7z3.fsf@shell.xmission.com> (permalink) |
| References | (16 earlier) <k1jm6i$s5k$1@dont-email.me> <zSs%r.2724$Wh5.2588@newsfe14.iad> <k1lo7d$835$1@dont-email.me> <k1oqsq$p0u$1@dont-email.me> <k1p4rh$im0$1@dont-email.me> |
Eric Sosman <esosman@ieee-dot-org.invalid> writes:
> On 8/30/2012 6:52 PM, Daniele Futtorovic wrote:
>> On 29/08/2012 20:49, Eric Sosman allegedly wrote:
>>> On 8/29/2012 2:06 PM, Daniel Pitts wrote:
>>>> On 8/28/12 5:02 PM, markspace wrote:
>>>>> On 8/28/2012 4:33 PM, Daniel Pitts wrote:
>>>>>>
>>>>>> interface Hasher<Type> {
>>>>>> int hash(Type t);
>>>>>
>>> The difficulty is that an external Hasher would have no access to
>>> private fields (...)
>>
>> This.
>
> ?
>
> package deal;
> public class ToBeHashed {
> private int noGettersForMeThanks;
> ...
> }
>
> package express;
> Hasher<ToBeHashed> hasher = new Hasher<ToBeHashed>() {
> public int hashCode(ToBeHashed obj) {
> // How do you obtain the value of
> // obj.noGettersForMeThanks
> // if that would be useful?
> }
> ...
> }
>
> As an example of why a hasher might want access to a strictly-private
> field, I offered String: How could a Hasher<String> (outside String
> itself) use String's private `hash' element? (And before you say
> "Give String a getHash() method," ponder what hashCode() does.)
I have, and I don't see a problem. String can define hashCode(), and
hashCodeIgnoreCase(), and hashCode(Locale), if those turn out to be
useful things to do for that particular class (String is an exceptional
class in several ways). The objection is to building hashCode() into
the Object hierarchy and hard-coding its use in HashMap. A separate
interface would allow more flexibility.
--
Jim Janney
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hashCode bob smith <bob@coolfone.comze.com> - 2012-08-10 08:47 -0700
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-10 12:13 -0400
Re: hashCode markspace <-@.> - 2012-08-10 10:13 -0700
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-10 13:38 -0400
Re: hashCode rossum <rossum48@coldmail.com> - 2012-08-11 10:36 +0100
Re: hashCode Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-10 12:34 -0400
Re: hashCode bob smith <bob@coolfone.comze.com> - 2012-08-10 15:22 -0700
Re: hashCode Lew <lewbloch@gmail.com> - 2012-08-10 15:32 -0700
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-10 19:30 -0400
Re: hashCode Lew <noone@lewscanon.com> - 2012-08-11 16:24 -0700
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-11 22:15 -0400
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-11 22:29 -0400
Re: hashCode Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-11 22:43 -0400
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-11 22:54 -0400
Re: hashCode Lew <noone@lewscanon.com> - 2012-08-11 21:46 -0700
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-12 16:53 -0400
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-12 17:00 -0400
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-10 19:27 -0400
Re: hashCode Robert Klemme <shortcutter@googlemail.com> - 2012-08-12 17:06 +0200
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-12 16:59 -0400
Re: hashCode Robert Klemme <shortcutter@googlemail.com> - 2012-08-13 19:17 +0200
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-19 19:42 -0400
Re: hashCode Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2012-08-21 10:30 +0000
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-19 19:47 -0400
Re: hashCode Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2012-08-21 10:43 +0000
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-27 19:04 -0400
Re: hashCode Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-08-27 16:55 -0700
Re: hashCode markspace <-@.> - 2012-08-27 17:03 -0700
Re: hashCode Lew <lewbloch@gmail.com> - 2012-08-27 17:49 -0700
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-27 21:37 -0400
Re: hashCode Patricia Shanahan <pats@acm.org> - 2012-08-27 18:58 -0700
Re: hashCode markspace <-@.> - 2012-08-27 21:19 -0700
Re: hashCode Patricia Shanahan <pats@acm.org> - 2012-08-28 01:06 -0700
Re: hashCode markspace <-@.> - 2012-08-28 09:19 -0700
Re: hashCode Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-08-28 16:33 -0700
Re: hashCode markspace <-@.> - 2012-08-28 17:02 -0700
Re: hashCode Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-08-29 11:06 -0700
Re: hashCode Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-29 14:49 -0400
Re: hashCode Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-08-29 13:40 -0700
Re: hashCode Gene Wirchenko <genew@ocis.net> - 2012-08-29 18:02 -0700
Re: hashCode Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2012-08-31 00:52 +0200
Re: hashCode Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-30 21:43 -0400
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-30 21:52 -0400
Re: hashCode Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2012-08-31 04:18 +0200
Re: hashCode Jim Janney <jjanney@shell.xmission.com> - 2012-08-31 09:08 -0600
Re: hashCode Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-31 11:38 -0400
Re: hashCode Robert Klemme <shortcutter@googlemail.com> - 2012-08-31 17:55 +0200
Re: hashCode Jim Janney <jjanney@shell.xmission.com> - 2012-08-31 09:56 -0600
Re: hashCode Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-31 14:32 -0400
Re: hashCode Jim Janney <jjanney@shell.xmission.com> - 2012-08-31 14:38 -0600
Re: hashCode Lew <lewbloch@gmail.com> - 2012-08-31 15:33 -0700
Re: hashCode Jim Janney <jjanney@shell.xmission.com> - 2012-08-31 16:41 -0600
Re: hashCode Lew <lewbloch@gmail.com> - 2012-08-31 16:26 -0700
Re: hashCode Jim Janney <jjanney@shell.xmission.com> - 2012-09-02 11:54 -0600
Re: hashCode Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2012-09-03 00:47 +0200
Re: hashCode Jim Janney <jjanney@shell.xmission.com> - 2012-09-03 21:44 -0600
Re: hashCode Jim Janney <jjanney@shell.xmission.com> - 2012-08-31 09:08 -0600
Re: hashCode Robert Klemme <shortcutter@googlemail.com> - 2012-08-31 17:58 +0200
Re: hashCode markspace <-@.> - 2012-08-29 11:51 -0700
Re: hashCode Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-08-29 13:28 -0700
Re: hashCode markspace <-@.> - 2012-08-29 16:05 -0700
Re: hashCode Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-08-29 16:23 -0700
Re: hashCode Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-29 20:56 -0400
Re: hashCode Jan Burse <janburse@fastmail.fm> - 2012-08-30 11:19 +0200
Re: hashCode Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-08-30 10:03 -0700
Re: hashCode Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2012-08-30 18:34 +0000
Re: hashCode Jim Janney <jjanney@shell.xmission.com> - 2012-08-30 08:11 -0600
Re: hashCode Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-08-30 10:06 -0700
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-30 19:16 -0400
Re: hashCode Lew <lewbloch@gmail.com> - 2012-08-28 13:58 -0700
Re: hashCode Lew <lewbloch@gmail.com> - 2012-08-28 13:56 -0700
Re: hashCode Patricia Shanahan <pats@acm.org> - 2012-08-28 14:07 -0700
Re: hashCode Lew <lewbloch@gmail.com> - 2012-08-28 14:38 -0700
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-27 21:12 -0400
Re: hashCode Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-11 07:58 -0400
Re: hashCode Lew <noone@lewscanon.com> - 2012-08-11 16:29 -0700
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-11 22:16 -0400
Re: hashCode Patricia Shanahan <pats@acm.org> - 2012-08-12 03:46 -0700
Re: hashCode Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-08-12 12:23 -0400
Re: hashCode Patricia Shanahan <pats@acm.org> - 2012-08-12 09:40 -0700
Re: hashCode Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-12 13:59 -0400
Re: hashCode Patricia Shanahan <pats@acm.org> - 2012-08-12 11:17 -0700
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-12 17:02 -0400
Re: hashCode Jan Burse <janburse@fastmail.fm> - 2012-08-12 19:03 +0200
Re: hashCode Roedy Green <see_website@mindprod.com.invalid> - 2012-08-10 12:17 -0700
Re: hashCode Lew <lewbloch@gmail.com> - 2012-08-10 12:45 -0700
Re: hashCode Roedy Green <see_website@mindprod.com.invalid> - 2012-08-11 04:54 -0700
Re: hashCode Joerg Meier <joergmmeier@arcor.de> - 2012-08-11 18:25 +0200
Re: hashCode Mike Winter <usenet@michael-winter.me.invalid> - 2012-08-11 18:53 +0100
Re: hashCode Peter Duniho <NpOeStPeAdM@NnOwSlPiAnMk.com> - 2012-08-11 09:56 -0700
Re: hashCode Jan Burse <janburse@fastmail.fm> - 2012-08-11 18:58 +0200
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-11 22:40 -0400
Re: hashCode rossum <rossum48@coldmail.com> - 2012-08-11 18:47 +0100
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-10 19:25 -0400
Re: hashCode Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-11 08:00 -0400
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-11 09:49 -0400
Re: hashCode Jan Burse <janburse@fastmail.fm> - 2012-08-11 15:33 +0200
Re: hashCode Jan Burse <janburse@fastmail.fm> - 2012-08-11 15:34 +0200
Re: hashCode Lew <noone@lewscanon.com> - 2012-08-11 16:34 -0700
Re: hashCode Lew <noone@lewscanon.com> - 2012-08-11 16:37 -0700
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-11 22:19 -0400
Re: hashCode Lew <noone@lewscanon.com> - 2012-08-11 21:48 -0700
Re: hashCode Jan Burse <janburse@fastmail.fm> - 2012-08-12 12:08 +0200
Re: hashCode Jan Burse <janburse@fastmail.fm> - 2012-08-12 12:18 +0200
Re: hashCode Lew <noone@lewscanon.com> - 2012-08-12 11:27 -0700
Re: hashCode Arne Vajhøj <arne@vajhoej.dk> - 2012-08-12 17:11 -0400
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