Re: [hibernate-dev] Should we deprecate @Similarity

On 19 Jan 2013, at 5:15 PM, Sanne Grinovero <sanne(a)hibernate.org&gt; wrote: > Discussing about some hibernate-search-engine complexities with Hardy > on IRC, we came to the agreement that the way @Similarity behaves > today was a mistake, so we're proposing to deprecate it in 4.4. > > Reasoning follows. > > There is a strong requirement in Lucene that all operations on the > same index need to use the same Similarity implementation. We infer > the org.apache.lucene.search.Similarity to be used on a specific index > from either: > > - the similarity property from the configuration file, which is > positioned on an index name > - the @Similarity annotation positioned on an indexed entity > > The trouble is about all these options needing to be consistent; first > problem is there isn't a precedence rule: if one of them is not > specified, we assume the user is using the other way to configure > things. But also different entities might be sharing the same index, > which leads to needing to verify that at least the user isn't > specifying some contradictory option. > > This all gets more confusing when you introduce the notion of > dynamically added new entities (a feature used by Infinispan) and/or > Dynamic Sharding, in which the properties of some indexes might > conflict with the specified @Similarity, but we might notice this only > at runtime rather than at bootstrap. Failing to load a class at this > point is far more annoying to the users than to fail the health-check > at bootstrap time. > > So the proposal: > drop the @Similarity annotation and use properties exclusively. > Properties are more suited for this as they are set on a per-index > base, which is what matters in this case. > > Downside: > I guess lots of people where using a single index per type, and for > those there was no danger to simply specify a @Similarity. We lose > this straight-forward way of things, but I'd argue that if you're in > the business of specifying a custom Similarity, you're a very advanced > user and wouldn't mind setting a one-liner in your configuration file. > > Do we agree? +1 to all your points --Hardy _______________________________________________ hibernate-dev mailing list hibernate-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/hibernate-dev