org.apache.lucene.search
Interface Searchable

All Superinterfaces:

Remote

All Known Implementing Classes:

RemoteSearchable, Searcher

public interface Searchable

extends Remote

The interface for search implementations.

Implementations provide search over a single index, over multiple indices, and over indices on remote servers.

Method Summary

void	close() Frees resources associated with this Searcher.
Document	doc(int i) Expert: Returns the stored fields of document i.
int	docFreq(Term term) Expert: Returns the number of documents containing term.
Explanation	explain(Query query, int doc) Returns an Explanation that describes how doc scored against query.
int	maxDoc() Expert: Returns one greater than the largest possible document number.
Query	rewrite(Query query) Expert: called to re-write queries into primitive queries.
void	search(Query query, Filter filter, HitCollector results) Lower-level search API.
TopDocs	search(Query query, Filter filter, int n) Expert: Low-level search implementation.

Method Detail

search

public void search(Query query,
                   Filter filter,
                   HitCollector results)
            throws IOException

Lower-level search API.

HitCollector.collect(int,float) is called for every non-zero scoring document.

Applications should only use this if they need all of the matching documents. The high-level search API (Searcher.search(Query)) is usually more efficient, as it skips non-high-scoring hits.

Parameters:

query - to match documents

filter - if non-null, a bitset used to eliminate some documents

results - to receive hits

Throws:

IOException

close

public void close()
           throws IOException

Frees resources associated with this Searcher.

Throws:

IOException

docFreq

public int docFreq(Term term)
            throws IOException

Expert: Returns the number of documents containing term. Called by search code to compute term weights.

Throws:

IOException

See Also:

IndexReader.docFreq(Term).

maxDoc

public int maxDoc()
           throws IOException

Expert: Returns one greater than the largest possible document number. Called by search code to compute term weights.

Throws:

IOException

See Also:

IndexReader.maxDoc().

search

public TopDocs search(Query query,
                      Filter filter,
                      int n)
               throws IOException

Expert: Low-level search implementation. Finds the top n hits for query, applying filter if non-null.

Called by Hits.

Applications should usually call Searcher.search(Query) or Searcher.search(Query,Filter) instead.

Throws:

IOException

doc

public Document doc(int i)
             throws IOException

Expert: Returns the stored fields of document i. Called by HitCollector implementations.

Throws:

IOException

See Also:

IndexReader.document(int).

rewrite

public Query rewrite(Query query)
              throws IOException

Expert: called to re-write queries into primitive queries.

Throws:

IOException

explain

public Explanation explain(Query query,
                           int doc)
                    throws IOException

Returns an Explanation that describes how doc scored against query.

This is intended to be used in developing Similarity implementations, and, for good performance, should not be displayed with every hit. Computing an explanation is as expensive as executing the query over the entire index.

Throws:

IOException