Package org.apache.lucene.queries

Class BooleanFilter

java.lang.Object

org.apache.lucene.search.Filter

org.apache.lucene.queries.BooleanFilter

All Implemented Interfaces:

Iterable<FilterClause>

public class BooleanFilter
extends Filter
implements Iterable<FilterClause>

A container Filter that allows Boolean composition of Filters. Filters are allocated into one of three logical constructs; SHOULD, MUST NOT, MUST The results Filter BitSet is constructed as follows: SHOULD Filters are OR'd together The resulting Filter is NOT'd with the NOT Filters The resulting Filter is AND'd with the MUST Filters

Constructor Summary

Constructors

Constructor	Description
BooleanFilter()

Method Summary

Modifier and Type	Method	Description
void	add(FilterClause filterClause)	Adds a new FilterClause to the Boolean Filter container
void	add(Filter filter, BooleanClause.Occur occur)
List<FilterClause>	clauses()	Returns the list of clauses
boolean	equals(Object obj)
DocIdSet	getDocIdSet(AtomicReaderContext context, Bits acceptDocs)	Returns the a DocIdSetIterator representing the Boolean composition of the filters that have been added.
int	hashCode()
Iterator<FilterClause>	iterator()	Returns an iterator on the clauses in this query.
String	toString()	Prints a user-readable version of this Filter.

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

BooleanFilter

public BooleanFilter()

Method Detail

getDocIdSet

public DocIdSet getDocIdSet(AtomicReaderContext context,
                            Bits acceptDocs)
                     throws IOException

Returns the a DocIdSetIterator representing the Boolean composition of the filters that have been added.

Specified by:

getDocIdSet in class Filter

Parameters:

context - a AtomicReaderContext 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 AtomicReader.fields() 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

add

public void add(FilterClause filterClause)

Adds a new FilterClause to the Boolean Filter container

Parameters:

filterClause - A FilterClause object containing a Filter and an Occur parameter

add

public final void add(Filter filter,
                      BooleanClause.Occur occur)

clauses

public List<FilterClause> clauses()

Returns the list of clauses

iterator

public final Iterator<FilterClause> iterator()

Returns an iterator on the clauses in this query. It implements the Iterable interface to make it possible to do:

for (FilterClause clause : booleanFilter) {}

Specified by:

iterator in interface Iterable<FilterClause>

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Prints a user-readable version of this Filter.

Overrides:

toString in class Object