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From Adrian Gonzalez <adr_gonza...@yahoo.fr>
Subject Re : Re : Convert List to Map
Date Fri, 12 Jun 2009 21:56:52 GMT
That's exactly what I was talking about !

Has it done its way to commons collection ? (I don't see it in 3.2.1 or in JIRA)

Code extract from http://mail-archives.apache.org/mod_mbox/commons-dev/200709.mbox/<f2e8eedf0709032030s1665dd5g36797577927d221c@mail.gmail.com>
:

Map<K,V> CollectionUtils.toMap(Collection<C> input,
Transformer<C,K> keyTransformer, Transformer<C,V>
valueTransformer, Map<K,V> map)
or
Map<K,V> CollectionUtils.toMap(Collection<C> input,
Transformer<C,K> keyTransformer, Transformer<C,V>
valueTransformer)







________________________________
De : James Carman <james@carmanconsulting.com>
À : Commons Users List <user@commons.apache.org>
Envoyé le : Vendredi, 12 Juin 2009, 17h27mn 03s
Objet : Re: Re : Convert List to Map

We had a discussion of something like what you're asking for in the past:

http://mail-archives.apache.org/mod_mbox/commons-dev/200709.mbox/<f2e8eedf0709032030s1665dd5g36797577927d221c@mail.gmail.com>


On Fri, Jun 12, 2009 at 10:55 AM, Adrian Gonzalez<adr_gonzalez@yahoo.fr> wrote:
> Thanks
>
> Your sample works fine for my use case (that's exactly what I'm doing in my code), but
I was wondering about such utility thing just after looking at :
> http://commons.apache.org/collections/api-release/org/apache/commons/collections/map/TransformedMap.html#decorate(java.util.Map,%20org.apache.commons.collections.Transformer,%20org.apache.commons.collections.Transformer)
> which is a map-to-map conversions.
>
> Since commons-collection provides map-to-map conversion, why does'nt it provide list-to-map
conversion with the same logic ?
>
>
>
>
>
> ________________________________
> De : Ted Dunning <ted.dunning@gmail.com>
> À : Commons Users List <user@commons.apache.org>
> Envoyé le : Jeudi, 11 Juin 2009, 23h12mn 10s
> Objet : Re: Convert List to Map
>
> How is this easier than this:
>
> Map m = new HashMap();
> for (SpecificObject x : list) {
>    m.put(s.getId(), s.getDescription());
> }
>
> ?
>
> Why make this soo much harder than it needs to be?
>
> On Wed, Jun 10, 2009 at 12:19 PM, Adrian Gonzalez <adr_gonzalez@yahoo.fr>wrote:
>
>> Hello,
>>
>> I have the same question as
>> http://mail-archives.apache.org/mod_mbox/commons-user/200509.mbox/%3C878e7290050905002752ed543d@mail.gmail.com%3E:
>>
>> I need to do a lot of list-to-map conversions, and I'm looking for a way to
>> use commons collections for this.
>> I would like to do something like this:
>>
>> Map map = ListUtils.toMap(list, new SomeTransformerInterface() {
>>    void insertIntoMap(Object object, Map map) {
>>    SpecificObject s = (SpecificObject) object;
>>    map.put(s.getId(), s.getDescription());
>>    }
>> });
>>
>> Is there a way to do that with commons collection ?
>>
>> Thank you very much
>>
>>
>>
>
>
>
>
> --
> Ted Dunning, CTO
> DeepDyve
>
> 111 West Evelyn Ave. Ste. 202
> Sunnyvale, CA 94086
> http://www.deepdyve.com
> 858-414-0013 (m)
> 408-773-0220 (fax)
>
>
>
>

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