org.apache.solr.search

Class Filter

java.lang.Object

org.apache.lucene.search.Query

org.apache.solr.search.Filter

Direct Known Subclasses:

QueryWrapperFilter, SolrFilter

public abstract class Filter
extends Query

Convenient base class for building queries that only perform matching, but no scoring. The scorer produced by such queries always returns 0 as score.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Filter() Default Filter constructor that will use the doc id set iterator when consumed through the Query API.
protected	Filter(boolean applyLazily) Filter constructor.

Method Summary

Modifier and Type	Method and Description
Weight	createWeight(IndexSearcher searcher, boolean needsScores, float boost)
abstract DocIdSet	getDocIdSet(LeafReaderContext context, Bits acceptDocs) Creates a DocIdSet enumerating the documents that should be permitted in search results.

Methods inherited from class org.apache.lucene.search.Query

classHash, equals, hashCode, rewrite, sameClassAs, toString, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

Filter

protected Filter(boolean applyLazily)

Filter constructor. When applyLazily is true and the produced DocIdSets support random-access, Lucene will only apply this filter after other clauses.

Filter

protected Filter()

Default Filter constructor that will use the doc id set iterator when consumed through the Query API.

Method Detail

getDocIdSet

public abstract DocIdSet getDocIdSet(LeafReaderContext context,
                                     Bits acceptDocs)
                              throws IOException

Creates a DocIdSet enumerating the documents that should be permitted in search results. NOTE: null can be returned if no documents are accepted by this Filter.

Note: This method will be called once per segment in the index during searching. The returned DocIdSet must refer to document IDs for that segment, not for the top-level reader.

Parameters:

context - a LeafReaderContext instance opened on the index currently searched on. Note, it is likely that the provided reader info does not represent the whole underlying index i.e. if the index has more than one segment the given reader only represents a single segment. The provided context is always an atomic context, so you can call LeafReader.terms(String) on the context's reader, for example.

acceptDocs - Bits that represent the allowable docs to match (typically deleted docs but possibly filtering other documents)

Returns:

a DocIdSet that provides the documents which should be permitted or prohibited in search results. NOTE: null should be returned if the filter doesn't accept any documents otherwise internal optimization might not apply in the case an empty DocIdSet is returned.

Throws:

IOException

createWeight

public Weight createWeight(IndexSearcher searcher,
                           boolean needsScores,
                           float boost)
                    throws IOException

Overrides:

createWeight in class Query

Throws:

IOException