RE: [Tm4j-developers] Index interface proposal checked in

[Kal A. <ka...@te...>]

I have just checked in a cleaned up version of the index interfaces for a 
quick peer review before I start coding some implementations of this stuff.

All comments welcome.

Cheers,

Kal

At 11:07 27/02/2002 +0000, Kal Ahmed wrote:

>Oops - forgot to cc the list on this one.
>
>>Date: Wed, 27 Feb 2002 09:28:10 +0000
>>To: "Florian G. Haas" <f.g...@gm...>
>>From: Kal Ahmed <ka...@te...>
>>Subject: RE: [Tm4j-developers] Index interface proposal checked in
>>
>>At 00:25 27/02/2002 +0100, you wrote:
>>>Hello!
>>>
>>>I must admit I'm certainly no expert at this, but what you are saying about
>>>the general purpose of these indexing mechanisms makes sense to me. Having
>>>had a look at the interface definitions themselves, I have a couple of
>>>questions:
>>>
>>>* What's the difference between an "open" and an "initialized" index? In
>>>other words, how would IndexProvider.getIndex().isOpen() be different from
>>>IndexProvider.getIndexMeta().isInitialised()? And how would that, in turn,
>>>differ from IndexManager.getIndexMetaData().isInitialised()?
>>
>>I think that is an inconsistency that needs to be removed. The close() 
>>method was actually added after I had sketched out the design, so I think 
>>that changing "initialise" to "open" in most places would make sense.
>>
>>The difference between IndexProvider and IndexManager is that a 
>>IndexProvider is essentially an SPI (service provider interface) that 
>>needs to be implemented by developers wishing to add their own indexes to 
>>a TM4J application. IndexManager is an API for developers wishing to use 
>>indexes through TM4J. So there should be no way for a "user" of the 
>>IndexManager interface to ever get hold of a handle to the IndexProvider 
>>- hence the extra layers.
>>
>>I think that the IndexMeta.isInitialised should probably be removed - 
>>that is more state information than meta information about the index. I 
>>think that the state information should be accessible through the Index 
>>object itself.
>>
>>I'll update the interfaces accordingly.
>>
>>>* What would be an "explicit runtime initialisation" as mentioned in the
>>>documentation for IndexManager?
>>
>>My thought was that some of these indexes might be quite heavy in terms 
>>of local resources used and so you wouldn't necessarily want them open as 
>>soon as the IndexProvider is loaded (seeing as an IndexProvider might be 
>>providing a set of indexes). So I originally intended explicit runtime 
>>initilisation to be the act of calling IndexProvider.getIndex(), but I 
>>think in retrospect that adding Index.open() would make sense and would 
>>put the explicit initialisation in the right place.
>>
>>Cheers,
>>
>>Kal
>
>
>_______________________________________________
>Tm4j-developers mailing list
>Tm4...@li...
>https://lists.sourceforge.net/lists/listinfo/tm4j-developers
>