Package org.apache.lucene.monitor

Class RegexpQueryHandler

java.lang.Object

org.apache.lucene.monitor.RegexpQueryHandler

All Implemented Interfaces:

CustomQueryHandler

public class RegexpQueryHandler
extends Object
implements CustomQueryHandler

A query handler implementation that matches Regexp queries by indexing regex terms by their longest static substring, and generates ngrams from Document tokens to match them.

This implementation will filter out more wildcard queries than TermFilteredPresearcher, at the expense of longer document build times. Which one is more performant will depend on the type and number of queries registered in the Monitor, and the size of documents to be monitored. Profiling is recommended.

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_MAX_TOKEN_SIZE	The default maximum length of an input token before ANYTOKENS are generated
static final String	DEFAULT_NGRAM_SUFFIX	The default suffix with which to mark ngrams
static final String	DEFAULT_WILDCARD_TOKEN	The default token to emit if a term is longer than MAX_TOKEN_SIZE

Constructor Summary

Constructors

Constructor	Description
RegexpQueryHandler()	Creates a new RegexpQueryHandler using default settings
RegexpQueryHandler(int maxTokenSize)	Creates a new RegexpQueryHandler with a maximum token size
RegexpQueryHandler(String ngramSuffix, int maxTokenSize, String wildcardToken, Set<String> excludedFields)	Creates a new RegexpQueryHandler

Method Summary

Modifier and Type	Method	Description
QueryTree	handleQuery(Query q, TermWeightor termWeightor)	Builds a QueryTree node from a query
TokenStream	wrapTermStream(String field, TokenStream ts)	Adds additional processing to the TokenStream over a document's terms index

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_NGRAM_SUFFIX

public static final String DEFAULT_NGRAM_SUFFIX

The default suffix with which to mark ngrams

See Also:

• Constant Field Values

DEFAULT_MAX_TOKEN_SIZE

public static final int DEFAULT_MAX_TOKEN_SIZE

The default maximum length of an input token before ANYTOKENS are generated

See Also:

• Constant Field Values

DEFAULT_WILDCARD_TOKEN

public static final String DEFAULT_WILDCARD_TOKEN

The default token to emit if a term is longer than MAX_TOKEN_SIZE

See Also:

• Constant Field Values

Constructor Details

RegexpQueryHandler

public RegexpQueryHandler(String ngramSuffix,
 int maxTokenSize,
 String wildcardToken,
 Set<String> excludedFields)

Creates a new RegexpQueryHandler

Parameters:

ngramSuffix - the suffix with which to mark ngrams

maxTokenSize - the maximum length of an input token before WILDCARD tokens are generated

wildcardToken - the token to emit if a token is longer than maxTokenSize in length

excludedFields - a Set of fields to ignore when generating ngrams

RegexpQueryHandler

public RegexpQueryHandler()

Creates a new RegexpQueryHandler using default settings

RegexpQueryHandler

public RegexpQueryHandler(int maxTokenSize)

Creates a new RegexpQueryHandler with a maximum token size

Parameters:

maxTokenSize - the maximum length of an input token before WILDCARD tokens are generated

Method Details

wrapTermStream

public TokenStream wrapTermStream(String field,
 TokenStream ts)

Description copied from interface: CustomQueryHandler

Adds additional processing to the TokenStream over a document's terms index

Specified by:

wrapTermStream in interface CustomQueryHandler

handleQuery

public QueryTree handleQuery(Query q,
 TermWeightor termWeightor)

Description copied from interface: CustomQueryHandler

Builds a QueryTree node from a query

Specified by:

handleQuery in interface CustomQueryHandler