org.apache.lucene.facet.search
Class DrillDownQuery

java.lang.Object
  org.apache.lucene.search.Query
      org.apache.lucene.facet.search.DrillDownQuery

All Implemented Interfaces:

Cloneable

public final class DrillDownQuery
extends Query

A Query for drill-down over categories. You should call add(CategoryPath...) for every group of categories you want to drill-down over. Each category in the group is OR'ed with the others, and groups are AND'ed.

NOTE: if you choose to create your own Query by calling term(org.apache.lucene.facet.params.FacetIndexingParams, org.apache.lucene.facet.taxonomy.CategoryPath), it is recommended to wrap it with ConstantScoreQuery and set the boost to 0.0f, so that it does not affect the scores of the documents.

WARNING: This API is experimental and might change in incompatible ways in the next release.

Constructor Summary

DrillDownQuery(FacetIndexingParams fip)
Creates a new DrillDownQuery without a base query, to perform a pure browsing query (equivalent to using MatchAllDocsQuery as base).

DrillDownQuery(FacetIndexingParams fip, Query baseQuery)
Creates a new DrillDownQuery over the given base query.

Method Summary

void	add(CategoryPath... paths) Adds one dimension of drill downs; if you pass multiple values they are OR'd, and then the entire dimension is AND'd against the base query.
DrillDownQuery	clone()
boolean	equals(Object obj)
int	hashCode()
Query	rewrite(IndexReader r)
static Term	term(FacetIndexingParams iParams, CategoryPath path) Return a drill-down Term for a category.
String	toString(String field)

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

createWeight, extractTerms, getBoost, setBoost, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

DrillDownQuery

public DrillDownQuery(FacetIndexingParams fip)

Creates a new DrillDownQuery without a base query, to perform a pure browsing query (equivalent to using MatchAllDocsQuery as base).

DrillDownQuery

public DrillDownQuery(FacetIndexingParams fip,
                      Query baseQuery)

Creates a new DrillDownQuery over the given base query. Can be null, in which case the result Query from rewrite(IndexReader) will be a pure browsing query, filtering on the added categories only.

Method Detail

term

public static Term term(FacetIndexingParams iParams,
                        CategoryPath path)

Return a drill-down Term for a category.

add

public void add(CategoryPath... paths)

Adds one dimension of drill downs; if you pass multiple values they are OR'd, and then the entire dimension is AND'd against the base query.

clone

public DrillDownQuery clone()

Overrides:

clone in class Query

hashCode

public int hashCode()

Overrides:

hashCode in class Query

equals

public boolean equals(Object obj)

Overrides:

equals in class Query

rewrite

public Query rewrite(IndexReader r)
              throws IOException

Overrides:

rewrite in class Query

Throws:

IOException

toString

public String toString(String field)

Specified by:

toString in class Query