In my project, we allow the user to click the last page link, so if the n specified is less than the totalHits, exception will be thrown.
I've changed to my code to like this

        set N to default number of docs to be retrieved
        Query query = qp.parse(keyword);
        Filter filter = getQueryFilter(parameter);
        Sort sort = getSort(parameter);
        TopDocs topFieldDocs = searcher.search(query,
            filter,N, sort);
        if(N<topFieldDocs.totalHits)
            topFieldDocs = searcher.search(query, filter, topFieldDocs.totalHits, sort);

In this way, i can achieve my goal.

2009/4/4 ΡΡ <ww.wang.cs@gmail.com>
thanks a lot, i got it

2009/4/4 Chris Hostetter <hossman_lucene@fucit.org>


: The problem comes as in this procedure i has to set the third parameter n
: and as a result, when user click the last page link, exception will be
: thrown when the total number of search results excesses the *n* i specified
: in the program. How can i overcome this problem?

you're going to need to change "n" ... typically people just use something
like...
       int n = DOCS_PER_PAGE * page_num

have you looked at the Lucene Demo code?  it has a more complex example of
doing a paginated search (grep for doPagingSearch) ...

http://svn.apache.org/viewvc/lucene/java/trunk/src/demo/org/apache/lucene/demo/SearchFiles.java?view=markup


: I've posted this problem twice and seen no reply. Could anyone offer a
: hand?  Thanks.

You should consider posting to the java-user@lucene mailing list which
is specificly focused on discussions of using hte java API ...
general@lucene is a broader list for discussions about the braoder Lucene
project, or as a getting started point for people who aren't even sure
which Lucene technology (PyLucene, Lucene-Java, Solr, Mahout, Nutch,
etc...) might be useful for them.




-Hoss




--
ΡΡ(Weiwei Wang)
Department of Computer Science
Gulou Campus of Nanjing University
Nanjing, P.R.China, 210093

Mobile: 86-13913310569
MSN: ww.wang.cs@gmail.com
Homepage: http://cs.nju.edu.cn/rl/weiweiwang



--
ΡΡ(Weiwei Wang)
Department of Computer Science
Gulou Campus of Nanjing University
Nanjing, P.R.China, 210093

Mobile: 86-13913310569
MSN: ww.wang.cs@gmail.com
Homepage: http://cs.nju.edu.cn/rl/weiweiwang