IndexSearcher

Creates a searcher searching the index in the named directory, with readOnly=true

Creates a searcher searching the index in the named directory. You should pass readOnly=true, since it gives much better concurrent performance, unless you intend to do write operations (delete documents or change norms) with the underlying IndexReader.

Creates a searcher searching the provided index.

Runs searches for each segment separately, using the provided ExecutorService. IndexSearcher will not shutdown/awaitTermination this ExecutorService on close; you must do so, eventually, on your own. NOTE: if you are using NIOFSDirectory, do not use the shutdownNow method of ExecutorService as this uses Thread.interrupt under-the-hood which can silently close file descriptors (see LUCENE-2239).

Expert: directly specify the reader, subReaders and their docID starts.

Expert: directly specify the reader, subReaders and their docID starts, and an ExecutorService. In this case, each segment will be separately searched using the ExecutorService. IndexSearcher will not shutdown/awaitTermination this ExecutorService on close; you must do so, eventually, on your own. NOTE: if you are using NIOFSDirectory, do not use the shutdownNow method of ExecutorService as this uses Thread.interrupt under-the-hood which can silently close file descriptors (see LUCENE-2239).

Note that the underlying IndexReader is not closed, if IndexSearcher was constructed with IndexSearcher(IndexReader r). If the IndexReader was supplied implicitly by specifying a directory, then the IndexReader is closed.

Returns the stored fields of document i.

Get the Document at the n^th position. The FieldSelector may be used to determine what Fields to load and how they should be loaded. NOTE: If the underlying Reader (more specifically, the underlying FieldsReader) is closed before the lazy Field is loaded an exception may be thrown. If you want the value of a lazy Field to be available after closing you must explicitly load it or fetch the Document again with a new loader.

Returns total docFreq for this term.

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.

Expert: low-level implementation method Returns an Explanation that describes how doc scored against weight.

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.

Applications should call explain(Query, int).

Return the IndexReader this searches.

Expert: Return the Similarity implementation used by this Searcher.

This defaults to the current value of getDefault().

Returns the atomic subReaders used by this searcher.

Expert: Returns one greater than the largest possible document number.

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

Lower-level search API.

collect(int) is called for every matching document.
Collector-based access to remote indexes is discouraged.

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

Finds the top n hits for query, applying filter if non-null.

Finds the top n hits for query.

Search implementation with arbitrary sorting and no filter.

Lower-level search API.

collect(int) is called for every document.
Collector-based access to remote indexes is discouraged.

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

Search implementation with arbitrary sorting. Finds the top n hits for query, applying filter if non-null, and sorting the hits by the criteria in sort.

NOTE: this does not compute scores by default; use setDefaultFieldSortScoring(boolean, boolean) to enable scoring.

Lower-level search API.

collect(int) is called for every matching document.

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

Note: The score passed to this method is a raw score. In other words, the score will not necessarily be a float whose value is between 0 and 1.

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

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

Expert: Low-level search implementation with arbitrary sorting. Finds the top n hits for query, applying filter if non-null, and sorting the hits by the criteria in sort.

Applications should usually call search(Query, Filter, int, Sort) instead.

By default, no scores are computed when sorting by field (using search(Query, Filter, int, Sort)). You can change that, per IndexSearcher instance, by calling this method. Note that this will incur a CPU cost.

Expert: Set the Similarity implementation used by this Searcher.

creates a weight for query

Just like search(Weight, Filter, int, Sort), but you choose whether or not the fields in the returned FieldDoc instances should be set by specifying fillFields.

NOTE: this does not compute scores by default. If you need scores, create a TopFieldCollector instance by calling create(Sort, int, boolean, boolean, boolean, boolean) and then pass that to search(Weight, Filter, Collector).