org.apache.lucene.search.suggest.analyzing

Class AnalyzingInfixSuggester

java.lang.Object

org.apache.lucene.search.suggest.Lookup

org.apache.lucene.search.suggest.analyzing.AnalyzingInfixSuggester

All Implemented Interfaces:

Closeable, AutoCloseable

Direct Known Subclasses:

BlendedInfixSuggester

public class AnalyzingInfixSuggester
extends Lookup
implements Closeable

Analyzes the input text and then suggests matches based on prefix matches to any tokens in the indexed text. This also highlights the tokens that match.

This just uses an ordinary Lucene index. It supports payloads, and records these as a BinaryDocValues field. Matches are sorted only by the suggest weight; it would be nice to support blended score + weight sort in the future. This means this suggester best applies when there is a strong apriori ranking of all the suggestions.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.search.suggest.Lookup

Lookup.LookupPriorityQueue, Lookup.LookupResult

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_MIN_PREFIX_CHARS Default minimum number of leading characters before PrefixQuery is used (4).

Fields inherited from class org.apache.lucene.search.suggest.Lookup

CHARSEQUENCE_COMPARATOR

Constructor Summary

Constructors

Constructor and Description
AnalyzingInfixSuggester(Version matchVersion, File indexPath, Analyzer analyzer) Create a new instance, loading from a previously built directory, if it exists.
AnalyzingInfixSuggester(Version matchVersion, File indexPath, Analyzer indexAnalyzer, Analyzer queryAnalyzer, int minPrefixChars) Create a new instance, loading from a previously built directory, if it exists.

Method Summary

Modifier and Type	Method and Description
void	build(InputIterator iter) Builds up a new internal Lookup representation based on the given InputIterator.
void	close()
long	getCount() Get the number of entries the lookup was built with
boolean	load(DataInput out) Discard current lookup data and load it from a previously saved copy.
List<Lookup.LookupResult>	lookup(CharSequence key, boolean onlyMorePopular, int num) Look up a key and return possible completion for this key.
List<Lookup.LookupResult>	lookup(CharSequence key, int num, boolean allTermsRequired, boolean doHighlight) Retrieve suggestions, specifying whether all terms must match (allTermsRequired) and whether the hits should be highlighted (doHighlight).
long	sizeInBytes() Get the size of the underlying lookup implementation in memory
boolean	store(DataOutput in) Persist the constructed lookup data to a directory.

Methods inherited from class org.apache.lucene.search.suggest.Lookup

build, load, store

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_MIN_PREFIX_CHARS

public static final int DEFAULT_MIN_PREFIX_CHARS

Default minimum number of leading characters before PrefixQuery is used (4).

See Also:

Constant Field Values

Constructor Detail

AnalyzingInfixSuggester

public AnalyzingInfixSuggester(Version matchVersion,
                               File indexPath,
                               Analyzer analyzer)
                        throws IOException

Create a new instance, loading from a previously built directory, if it exists.

Throws:

IOException

AnalyzingInfixSuggester

public AnalyzingInfixSuggester(Version matchVersion,
                               File indexPath,
                               Analyzer indexAnalyzer,
                               Analyzer queryAnalyzer,
                               int minPrefixChars)
                        throws IOException

Create a new instance, loading from a previously built directory, if it exists.

Parameters:

minPrefixChars - Minimum number of leading characters before PrefixQuery is used (default 4). Prefixes shorter than this are indexed as character ngrams (increasing index size but making lookups faster).

Throws:

IOException

Method Detail

build

public void build(InputIterator iter)
           throws IOException

Description copied from class: Lookup

Builds up a new internal Lookup representation based on the given InputIterator. The implementation might re-sort the data internally.

Specified by:

build in class Lookup

Throws:

IOException

lookup

public List<Lookup.LookupResult> lookup(CharSequence key,
                                        boolean onlyMorePopular,
                                        int num)

Description copied from class: Lookup

Look up a key and return possible completion for this key.

Specified by:

lookup in class Lookup

Parameters:

key - lookup key. Depending on the implementation this may be a prefix, misspelling, or even infix.

onlyMorePopular - return only more popular results

num - maximum number of results to return

Returns:

a list of possible completions, with their relative weight (e.g. popularity)

lookup

public List<Lookup.LookupResult> lookup(CharSequence key,
                                        int num,
                                        boolean allTermsRequired,
                                        boolean doHighlight)

Retrieve suggestions, specifying whether all terms must match (allTermsRequired) and whether the hits should be highlighted (doHighlight).

store

public boolean store(DataOutput in)
              throws IOException

Description copied from class: Lookup

Persist the constructed lookup data to a directory. Optional operation.

Specified by:

store in class Lookup

Parameters:

in - DataOutput to write the data to.

Returns:

true if successful, false if unsuccessful or not supported.

Throws:

IOException - when fatal IO error occurs.

load

public boolean load(DataInput out)
             throws IOException

Description copied from class: Lookup

Discard current lookup data and load it from a previously saved copy. Optional operation.

Specified by:

load in class Lookup

Parameters:

out - the DataInput to load the lookup data.

Returns:

true if completed successfully, false if unsuccessful or not supported.

Throws:

IOException - when fatal IO error occurs.

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException

sizeInBytes

public long sizeInBytes()

Description copied from class: Lookup

Get the size of the underlying lookup implementation in memory

Specified by:

sizeInBytes in class Lookup

Returns:

ram size of the lookup implementation in bytes

getCount

public long getCount()

Description copied from class: Lookup

Get the number of entries the lookup was built with

Specified by:

getCount in class Lookup

Returns:

total number of suggester entries