lucene-java-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Baozhen Jia" <jiabaoz...@gmail.com>
Subject Re: Singleton and Lucene: org.apache.lucene.store.AlreadyClosed
Date Tue, 16 Dec 2008 08:37:01 GMT
some docs from Lucene 2.4.0:
   * IndexReader new = r.reopen();
   * if (new != reader) {
   *   ...     // reader was reopened
   *   reader.close();
   * }
   * reader = new;

Did you follow this instruction?

It's bad in case of concurrent access in my opinion.

Do not close the reader, and try this:
org.apache.lucene.index.IndexReader.decRef() &
org.apache.lucene.index.IndexReader.incRef()


On Tue, Dec 16, 2008 at 6:06 AM, Zender00 <danielpenning@gmx.net> wrote:

>
> Hi Paul,
> thanks for your reply.
>
> I compared your source code and it seems that you are using the same
> mechanism for the singleton like me... I am using lucene 2.4 and get the
> exception above explained.
> I am wondering why because I only create an instance of my lucene object
> (which itself constructs an IndexReader/IndexWriter in its constructor) and
> return this instance to objects which want to execute some lucene
> operations. So I only applied the singleton-pattern.
> I am still wondering why these pattern results in my exception. Why could
> it
> happen, that these Streams (IndexWriter/IndexReader) close itself. In my
> opinion it is completely legal to do so.
>
> Any other suggestions?
>
>
>
> polx wrote:
> >
> >
> > Le 15-déc.-08 à 13:09, Zender00 a écrit :
> >> in my opinion it is possible to use a reader and writer
> >> simultanesously on
> >> the same index. In my already working lucene class, I use they are
> >> both open
> >> all the time.
> >
> > mmmh...
> >
> >> But this isnt the reason for my exception. It seems that lucene cannot
> >> handle my singleton. How did you implement your singleton with
> >> lucene? Which
> >> lucene version?
> >
> > 2.3.1, source code APL and GPL at:
> >    http://svn.activemath.org/intergeo/Platform/SearchI2G/index/
> >
> > in another project, this was used with Lucene 2.0.
> >
> > paul
> >
> >> polx wrote:
> >>>
> >>> We use singletons all the time,
> >>>
> >>> Just be careful that are writer and a reader cannot be opened
> >>> simultaneously on the same index. Either you write or your read (and
> >>> delete).
> >>>
> >>> paul
> >>>
> >>>
> >>> Le 15-déc.-08 à 12:06, Zender00 a écrit :
> >>>
> >>>>
> >>>> I extend my original post:
> >>>> How is it possible to use lucene in 2 diffent classes / objects, if
> >>>> I dont
> >>>> want to use static methods/variables?
> >>>> (one object read/writer, the other is read only)
> >>>>
> >>>> Kind regards,
> >>>> D. Penning
> >>>>
> >>>> Zender00 wrote:
> >>>>>
> >>>>> Hi,
> >>>>> I tried to implement a singleton pattern for my already working
> >>>>> lucene
> >>>>> object.
> >>>>> But there is a strange error when I tried to access the instance.
> >>>>>
> >>>>> When my Singleton GetInstance() method is executed for the first
> >>>>> time it
> >>>>> creates a new instance of my lucene object. There are some member
> >>>>> variables in this object like an IndexWriter and IndexReader. These
> >>>>> objects are created in the constructor and I can access them
> >>>>> directly in
> >>>>> the constructor successfully.
> >>>>> GetInstance() now returns this lucene object and I have to execute
> >>>>> some
> >>>>> operations on it. But the IndexWriter seems to be closed meanwhile
> >>>>> and I
> >>>>> got the exception:
> >>>>>
> >>>>> "org.apache.lucene.store.AlreadyClosed    Exception: this
> >>>>> IndexWriter is
> >>>>> closed" when my object tries to writer some documents.
> >>>>>
> >>>>> How could this happen? Isn't it possible to use lucene with a
> >>>>> singleton-pattern?
> >>>>>
> >>>>> Kind regards,
> >>>>> D. Penning
> >>>>>
> >>>>
> >>>> --
> >>>> View this message in context:
> >>>>
> http://www.nabble.com/Singleton-and-Lucene%3A-org.apache.lucene.store.AlreadyClosed-tp20983056p21011945.html
> >>>> Sent from the Lucene - Java Users mailing list archive at
> >>>> Nabble.com.
> >>>>
> >>>>
> >>>> ---------------------------------------------------------------------
> >>>> To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org
> >>>> For additional commands, e-mail: java-user-help@lucene.apache.org
> >>>>
> >>>
> >>>
> >>>
> >>>
> >>
> >> --
> >> View this message in context:
> >>
> http://www.nabble.com/Singleton-and-Lucene%3A-org.apache.lucene.store.AlreadyClosed-tp20983056p21012798.html
> >> Sent from the Lucene - Java Users mailing list archive at Nabble.com.
> >>
> >>
> >> ---------------------------------------------------------------------
> >> To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org
> >> For additional commands, e-mail: java-user-help@lucene.apache.org
> >>
> >
> >
> >
> >
>
> --
> View this message in context:
> http://www.nabble.com/Singleton-and-Lucene%3A-org.apache.lucene.store.AlreadyClosed-tp20983056p21022920.html
> Sent from the Lucene - Java Users mailing list archive at Nabble.com.
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org
> For additional commands, e-mail: java-user-help@lucene.apache.org
>
>


-- 
Jia Baozhen
Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message