org.apache.lucene.search

Class PrefixQuery

java.lang.Object

org.apache.lucene.search.Query

org.apache.lucene.search.MultiTermQuery

org.apache.lucene.search.AutomatonQuery

org.apache.lucene.search.PrefixQuery

All Implemented Interfaces:

Accountable

public class PrefixQuery
extends AutomatonQuery

A Query that matches documents containing terms with a specified prefix. A PrefixQuery is built by QueryParser for input like app*.

This query uses the MultiTermQuery.CONSTANT_SCORE_REWRITE rewrite method.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.search.MultiTermQuery

MultiTermQuery.RewriteMethod, MultiTermQuery.TopTermsBlendedFreqScoringRewrite, MultiTermQuery.TopTermsBoostOnlyBooleanQueryRewrite, MultiTermQuery.TopTermsScoringBooleanQueryRewrite

Field Summary

Fields inherited from class org.apache.lucene.search.AutomatonQuery

automaton, automatonIsBinary, compiled, term

Fields inherited from class org.apache.lucene.search.MultiTermQuery

CONSTANT_SCORE_BOOLEAN_REWRITE, CONSTANT_SCORE_REWRITE, field, rewriteMethod, SCORING_BOOLEAN_REWRITE

Fields inherited from interface org.apache.lucene.util.Accountable

NULL_ACCOUNTABLE

Constructor Summary

Constructors

Constructor and Description
PrefixQuery(Term prefix) Constructs a query for terms starting with prefix.

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj) Override and implement query instance equivalence properly in a subclass.
Term	getPrefix() Returns the prefix of this query.
int	hashCode() Override and implement query hash code properly in a subclass.
static Automaton	toAutomaton(BytesRef prefix) Build an automaton accepting all terms with the specified prefix.
String	toString(String field) Prints a user-readable version of this query.

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

getAutomaton, getTermsEnum, isAutomatonBinary, ramBytesUsed, visit

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

getField, getRewriteMethod, getTermsEnum, rewrite, setRewriteMethod

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

classHash, createWeight, sameClassAs, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.lucene.util.Accountable

getChildResources

Constructor Detail

PrefixQuery

public PrefixQuery(Term prefix)

Constructs a query for terms starting with prefix.

Method Detail

toAutomaton

public static Automaton toAutomaton(BytesRef prefix)

Build an automaton accepting all terms with the specified prefix.

getPrefix

public Term getPrefix()

Returns the prefix of this query.

toString

public String toString(String field)

Prints a user-readable version of this query.

Overrides:

toString in class AutomatonQuery

hashCode

public int hashCode()

Description copied from class: Query

Override and implement query hash code properly in a subclass. This is required so that QueryCache works properly.

Overrides:

hashCode in class AutomatonQuery

See Also:

Query.equals(Object)

equals

public boolean equals(Object obj)

Description copied from class: Query

Override and implement query instance equivalence properly in a subclass. This is required so that QueryCache works properly. Typically a query will be equal to another only if it's an instance of the same class and its document-filtering properties are identical that other instance. Utility methods are provided for certain repetitive code.

Overrides:

equals in class AutomatonQuery

See Also:

Query.sameClassAs(Object), Query.classHash()