Class NGramPhraseQuery

  extended by
      extended by
          extended by
All Implemented Interfaces:
Serializable, Cloneable

public class NGramPhraseQuery
extends PhraseQuery

This is a PhraseQuery which is optimized for n-gram phrase query. For example, when you query "ABCD" on a 2-gram field, you may want to use NGramPhraseQuery rather than PhraseQuery, because NGramPhraseQuery will rewrite(IndexReader) the query to "AB/0 CD/2", while PhraseQuery will query "AB/0 BC/1 CD/2" (where term/position).

See Also:
Serialized Form

Constructor Summary
NGramPhraseQuery(int n)
          Constructor that takes gram size.
Method Summary
 boolean equals(Object o)
          Returns true iff o is equal to this.
 int hashCode()
          Returns a hash code value for this object.
 Query rewrite(IndexReader reader)
          Expert: called to re-write queries into primitive queries.
Methods inherited from class
add, add, createWeight, extractTerms, getPositions, getSlop, getTerms, setSlop, toString
Methods inherited from class
clone, combine, getBoost, getSimilarity, mergeBooleanQueries, setBoost, toString, weight
Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail


public NGramPhraseQuery(int n)
Constructor that takes gram size.

n -
Method Detail


public Query rewrite(IndexReader reader)
              throws IOException
Description copied from class: Query
Expert: called to re-write queries into primitive queries. For example, a PrefixQuery will be rewritten into a BooleanQuery that consists of TermQuerys.

rewrite in class PhraseQuery


public boolean equals(Object o)
Returns true iff o is equal to this.

equals in class PhraseQuery


public int hashCode()
Returns a hash code value for this object.

hashCode in class PhraseQuery

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