Hi all
Sharpen from db4o could maybe replace jlca
My 2cents...
Vincent
Le 1 nov. 2010 à 21:55, George Aroush <geo...@aroush.net> a écrit :
Let me jump in here and offer some perspective about Lucene.Net
(btw, it's not Lucene.NET :-) ). This is based on my past
involvement with the project -- since 2003 when it was on SourceForge.net
and called dotLucene.
1) Up until early this year, I have been porting and supporting Lucene.Net
since ver 1.4 (back in 2004 on SourceForge.net) to the current
release on trunk ver. 2.9.2. This is in NO WAY to say that others
have not helped or contributed. I'm just saying that I know the
history and have the experience (I wrote and worked on search
engines from 1998 to 2002).
2) Doing an initial port of a new Java Lucene release to C# Lucene
is very hard; it's the most complex part of the port even using
automated tools such as JLCA and my own customize scripts which I
use pre-and port JLCA (you can search the listing on how I do the
port). What used to take me about 1 months with 90% of tests
passing took me well over 4 months (for 2.9.x) with only 10% of
tests passing. This was no easy effort and won't be easier now
since Java Lucene is using new Java language features that JLCA is
not aware of (MS is not maintaining JLCA). Put another way, porting
is hard especially when you are dealing with > 5.6 GB source code
consistent of > 610 source files. You will know this ONLY if you
have tried it out and maintained it -- this is why no one has
stepped up to do an initial port otherwise there would be a port by
now not only of Java Lucene but other projects too.
3) To simplify ports of new release, maintaining as small as
possible delta between release is very important. This was a main
pain point when I ported from 2.4 to 2.9. The in-between ports were
never done due to lack of time on my end. See point #2.
4) Diverging away from Java Lucene, both API base and algorithm is
risky and will just make point #2 more evidence. Not only will you
now need a deep knowledge of search engines to catch bugs, but also
a deep knowledge of Lucene's internals. Also, you risk
compatibility as well as books and existing resources on the web
that cover Lucene -- hack, one can take any Java Lucene example and
easily read it as a Lucene.Net code or use Luke to debug an index.
Keep in mind, the current port model that we have for Lucene.Net
keeps the API one-to-one in sync with Java Lucene; just upper case
method names. Yes, it's not fully .NET'es, but if you are looking
for a search engine that is compatible with the open source search
engine standard, and it is available in C#, Lucene.Net is it.
5) Beside making the port simpler, and per point #3 above, doing a
line-per-line port, and maintaining API naming as well as the
algorithm and file format of Java Lucene in C# Lucene means a Lucene
index created by Java Lucene is usable, concurrently, by C# Lucene.
I have worked on one such project where a Java and C# code accessing
the same index. I'm not too interested in making Lucene.Net .NET'es
and end up adding more risk to the project.
6) If anyone wants a different flavor of Lucene.Net, the code is on
Apache, just fork it and start a new project. Make it more .NET'es,
use the latest that .NET has to offer, and all. However, until when
you have first hand experience with the port, and a good knowledge
of Lucene and search engines, and the cycles to work on it, I really
don't want to exercise this idea it will die as I know few folks
have tried.
7) I can't speak for the other committers or those who contributed,
but for me, I do this totally during my own time. Each hour I spent
on Lucene.Net is an hour away from my family or anything else. I
don't get paid, and I hardly get much off my Luene.Net work on the
side. As you may know, I was active with Lucene.Net till about
early this year, (I had a family emergency). I want to step up
again, but we need more participation than just an offer to help or
request divergence from the goal of the project, per the points that
I made above.
I can go on, but the above are to clarify some of the issues and
background of Lucene.Net. Please keep those in mind when thinking
about this project and how you can contribute -- especially comments
about making Lucene.Net more .NET'es -- can't start that till when
you first achieve commit-per-commit port of Java Lucene to C# Lucene.
If you agree with the above, and it makes sense to you, my
suggestion is as follows:
1) Lucene.Net goes back into incubation and start all over again.
2) Start with cleaning up the webpage and make it more like other
Apache project site.
3) Put together an official Lucene.Net 2.9.2 and get it released.
4) Start working on the next port.
#2, #3 can happen right away, and all that it takes to do them is
coming up to speed on how-to using existing Apache documentation.
Who is up to this task?
#4 is a bit more complicated. I don't want to go through the port
pain that I had with 2.9.0 -- it was too much. JLCA that comes with
VS 2005 is out of date; I would love to try out a newer version from www.artinsoft.com
, but it is $$.
I hope the above helps and I have not offended or discouraged anyone
as it isn't my intention. I just want to clarify few things about Lucene.Net
PS: One final point. Look at CLucene, NLucene and few other
variation of Java Lucene ports that were done at Lucene internal
level with the goal of maintaining language look feature and look-
and-fell, such as C++, those projects are either way out of date in
terms of release version support or offer only partial support
(index read only). I don't want to use this to bad mouth another
project, but to make a point that porting is hard if you diverge
from the core. As is, Lucene.Net is not dead, it's slow and needs
contributors who will step-up.
Thanks,
-- George
