org.neo4j.index.impl.lucene

Class Hits

java.lang.Object

org.neo4j.index.impl.lucene.Hits

public final class Hits
extends Object

A ranked list of documents, used to hold search results.

Caution: Iterate only over the hits needed. Iterating over all hits is generally not desirable and may be the source of performance issues.

Note: Deleting matching documents concurrently with traversing the hits, might, when deleting hits that were not yet retrieved, decrease length(). In such case, ConcurrentModificationException is thrown when accessing hit n ≥ current_length() (but n < length()_at_start). see Searcher.search(org.apache.lucene.search.Query , int), Searcher.search(org.apache.lucene.search.Query , org.apache.lucene.search.Filter , int) and Searcher.search(org.apache.lucene.search.Query , org.apache.lucene.search.Filter , int, org.apache.lucene.search.Sort):

   TopDocs topDocs = searcher.search(query, numHits);
   ScoreDoc[] hits = topDocs.scoreDocs;
   for (int i = 0; i < hits.length; i++) {
     int docId = hits[i].doc;
     Document d = searcher.doc(docId);
     // do something with current hit
     ...
 

Constructor Summary

Constructors

Constructor and Description
Hits(org.apache.lucene.search.IndexSearcher s, org.apache.lucene.search.Query q, org.apache.lucene.search.Filter f)
Hits(org.apache.lucene.search.IndexSearcher s, org.apache.lucene.search.Query q, org.apache.lucene.search.Filter f, org.apache.lucene.search.Sort o, boolean score)

Method Summary

Methods

Modifier and Type	Method and Description
org.apache.lucene.document.Document	doc(int n) Returns the stored fields of the nth document in this set.
int	length() Returns the total number of hits available in this set.
float	score(int n) Returns the score for the nth document in this set.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Hits

public Hits(org.apache.lucene.search.IndexSearcher s,
    org.apache.lucene.search.Query q,
    org.apache.lucene.search.Filter f)
     throws IOException

Throws:

IOException

Hits

public Hits(org.apache.lucene.search.IndexSearcher s,
    org.apache.lucene.search.Query q,
    org.apache.lucene.search.Filter f,
    org.apache.lucene.search.Sort o,
    boolean score)
     throws IOException

Throws:

IOException

Method Detail

length

public int length()

Returns the total number of hits available in this set.

Returns:

the total number of hits available in this set

doc

public org.apache.lucene.document.Document doc(int n)
                                        throws org.apache.lucene.index.CorruptIndexException,
                                               IOException

Returns the stored fields of the n^th document in this set.

Documents are cached, so that repeated requests for the same element may return the same Document object.

Parameters:

n - the index of the document to get

Returns:

the stored fields of the document

Throws:

org.apache.lucene.index.CorruptIndexException - if the index is corrupt

IOException - if there is a low-level IO error

score

public float score(int n)
            throws IOException

Returns the score for the n^th document in this set.

Parameters:

n - the index of the document

Returns:

the score for the document

Throws:

IOException - if there is a low-level IO error