[infinispan-dev] [ISPN-32] API changes for query module

[Manik Surtani]

I don't see why this query interface needs to extend cache.  They are  
separate and coherent components.

The cache is a data structure that handles (distributed) caching of  
stuff.  A query operates on a cache.  So I prefer Galder's approach  
where you do:

List l = new DefaultQueryFactory(cache,  
Item.class).createQuery().setMaxResults(10).getResultList();

Cheers
Manik

On 3 Jul 2009, at 12:21, Emmanuel Bernard wrote:

> If you really want to split the query part out of the Cache API
> cache
> .specialize
> (QueryableCache
> .class).createQuery(luceneQuery).setMaxResults(20).getResultList();
>
> It's still 2 classes less a user needs to learn and remember to  
> simply do a query.
>
>
> On  Jul 3, 2009, at 12:40, Galder Zamarreno wrote:
>
>>
>>
>> On 07/02/2009 07:34 PM, Galder Zamarreno wrote:
>>>
>>>
>>> On 07/02/2009 07:12 PM, Emmanuel Bernard wrote:
>>>> doesn't work, to execute the query, you need to associate it with a
>>>> cache instance
>>>
>>> In that case, cache.createQuery() makes more sense.
>>
>> Actually, why not this?
>>
>> Cache cache = new DefaultCacheManager().getCache();
>> Query query = new  
>> DefaultQueryFactory(cache).getQuery().setMaxResults(20);
>> List<Item> results = query.getResultList();
>>
>> If you extend Cache, let's call it, QueryableCache you're gonna  
>> need something that creates that type of cache:
>>
>> QueryableCache cache = new QueryableCacheManager().getCache();
>> Query query = cache.createQuery().setMaxResults(20);
>> List<Item> results = query.getResultList();
>>
>> If in the future we're planning to offer the creation of different  
>> types of queries, I'd favor 1st option. Otherwise, 2nd option.
>>
>>>
>>>>
>>>> On Jul 2, 2009, at 18:48, Galder Zamarreno wrote:
>>>>
>>>>>
>>>>>
>>>>> On 07/02/2009 10:15 AM, Emmanuel Bernard wrote:
>>>>>>
>>>>>> On Jul 1, 2009, at 10:05, Galder Zamarreno wrote:
>>>>>>
>>>>>>>>
>>>>>>>> 3 - SearchableCache: -
>>>>>>>>
>>>>>>>> Should the name of this class be changed? I don't think so  
>>>>>>>> but if
>>>>>>>> anyone
>>>>>>>> has any ideas ...
>>>>>>>
>>>>>>> Here's my point of view:
>>>>>>>
>>>>>>> createQuery() looks to me like factory method and so I think  
>>>>>>> it would
>>>>>>> suit more a factory interface, i.e. QueryFactory? rather than  
>>>>>>> in an
>>>>>>> extension of Cache.
>>>>>>>
>>>>>>> IMO, extending Cache interface would make sense if you're  
>>>>>>> gonna add an
>>>>>>> operation against the searchable or queryable cache itself, such
>>>>>>> query(). But this method kind of implies that you actually  
>>>>>>> execute the
>>>>>>> query against the cache, so you'd imagine taking a CacheQuery as
>>>>>>> parameter. Bearing in mind my limited knowledge of how users  
>>>>>>> use JBC
>>>>>>> Searchable, I dunno if having such method makes sense or not.  
>>>>>>> If it
>>>>>>> does not, not a problem. Stick with a QueryFactory interface  
>>>>>>> that has
>>>>>>> a create() method that returns Query (or CacheQuery) and  
>>>>>>> that's it.
>>>>>>>
>>>>>>
>>>>>> Well except that your API will be just verbose and complex to  
>>>>>> use.
>>>>>> What's better?
>>>>>>
>>>>>> List<Item> results = cache.createQuery(luceneQuery,
>>>>>> Item.class).setMaxResults(20).getResultList();
>>>>>> or
>>>>>> Query q =  
>>>>>> cache.getCacheManager().getQueryFactory().create(luceneQuery,
>>>>>> Item.class)..setMaxResults(20);
>>>>>> List<Item> results = cache.query(q);
>>>>>>
>>>>>> in other words, who cares if it's a factory, a factory factory  
>>>>>> or an
>>>>>> abstract factory factory factory. People just want to create a  
>>>>>> query
>>>>>> and
>>>>>> get the result list.
>>>>>
>>>>> I don't see why you need to extend cache to create a query. I  
>>>>> said I
>>>>> wasn't sure whether cache needed a query method. Assuming that it
>>>>> doesn't needed, Here's how it looks cleaner to me:
>>>>>
>>>>> Cache cache = new DefaultCacheManager().getCache();
>>>>> Query query = new  
>>>>> DefaultQueryFactory().getQuery().setMaxResults(20);
>>>>> List<Item> results = query.getResultList();
>>>>>
>>>>> --
>>>>> Galder Zamarreño
>>>>> Sr. Software Engineer
>>>>> Infinispan, JBoss Cache
>>>>
>>>
>>
>> -- 
>> Galder Zamarreño
>> Sr. Software Engineer
>> Infinispan, JBoss Cache
>
>
> _______________________________________________
> infinispan-dev mailing list
> infinispan-dev at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/infinispan-dev

--
Manik Surtani
manik at jboss.org
Lead, Infinispan
Lead, JBoss Cache
http://www.infinispan.org
http://www.jbosscache.org