public class

PhraseQuery

extends Query
java.lang.Object
   ↳ org.apache.lucene.search.Query
     ↳ org.apache.lucene.search.PhraseQuery

Class Overview

A Query that matches documents containing a particular sequence of terms. A PhraseQuery is built by QueryParser for input like "new york".

This query may be combined with other terms or queries with a BooleanQuery.

Summary

Public Constructors
PhraseQuery()
Constructs an empty phrase query.
Public Methods
void add(Term term)
Adds a term to the end of the query phrase.
void add(Term term, int position)
Adds a term to the end of the query phrase.
Weight createWeight(Searcher searcher)
Expert: Constructs an appropriate Weight implementation for this query.
boolean equals(Object o)
Returns true iff o is equal to this.
void extractTerms(Set<Term> queryTerms)
Expert: adds all terms occurring in this query to the terms set.
int[] getPositions()
Returns the relative positions of terms in this phrase.
int getSlop()
Returns the slop.
Term[] getTerms()
Returns the set of terms in this phrase.
int hashCode()
Returns a hash code value for this object.
void setSlop(int s)
Sets the number of other words permitted between words in query phrase.
String toString(String f)
Prints a user-readable version of this query.
[Expand]
Inherited Methods
From class org.apache.lucene.search.Query
From class java.lang.Object

Public Constructors

public PhraseQuery ()

Constructs an empty phrase query.

Public Methods

public void add (Term term)

Adds a term to the end of the query phrase. The relative position of the term is the one immediately after the last term added.

public void add (Term term, int position)

Adds a term to the end of the query phrase. The relative position of the term within the phrase is specified explicitly. This allows e.g. phrases with more than one term at the same position or phrases with gaps (e.g. in connection with stopwords).

public Weight createWeight (Searcher searcher)

Expert: Constructs an appropriate Weight implementation for this query.

Only implemented by primitive queries, which re-write to themselves.

Throws
IOException

public boolean equals (Object o)

Returns true iff o is equal to this.

public void extractTerms (Set<Term> queryTerms)

Expert: adds all terms occurring in this query to the terms set. Only works if this query is in its rewritten form.

See Also

public int[] getPositions ()

Returns the relative positions of terms in this phrase.

public int getSlop ()

Returns the slop. See setSlop().

public Term[] getTerms ()

Returns the set of terms in this phrase.

public int hashCode ()

Returns a hash code value for this object.

public void setSlop (int s)

Sets the number of other words permitted between words in query phrase. If zero, then this is an exact phrase search. For larger values this works like a WITHIN or NEAR operator.

The slop is in fact an edit-distance, where the units correspond to moves of terms in the query phrase out of position. For example, to switch the order of two words requires two moves (the first move places the words atop one another), so to permit re-orderings of phrases, the slop must be at least two.

More exact matches are scored higher than sloppier matches, thus search results are sorted by exactness.

The slop is zero by default, requiring exact matches.

public String toString (String f)

Prints a user-readable version of this query.