org.dlese.dpc.index.queryParser
Class FieldExpansionQueryParser

java.lang.Object
  org.apache.lucene.queryParser.QueryParser
      org.dlese.dpc.index.queryParser.FieldExpansionQueryParser

All Implemented Interfaces:

QueryParserConstants

public class FieldExpansionQueryParser
extends QueryParser

A QueryParser that modifies a user's query by expanding the fields that are searched, applying boosting, and applying Query mappings for the given virtual field/terms. The static parse method must be used - see it's definition for details.

Author:

John Weatherley

See Also:

VirtualSearchFieldMapper

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.queryParser.QueryParser

QueryParser.Operator

Field Summary

Fields inherited from class org.apache.lucene.queryParser.QueryParser

AND_OPERATOR, jj_nt, OR_OPERATOR, token, token_source

Fields inherited from interface org.apache.lucene.queryParser.QueryParserConstants

_ESCAPED_CHAR, _NUM_CHAR, _QUOTED_CHAR, _TERM_CHAR, _TERM_START_CHAR, _WHITESPACE, AND, Boost, CARAT, COLON, DEFAULT, EOF, FUZZY_SLOP, LPAREN, MINUS, NOT, NUMBER, OR, PLUS, PREFIXTERM, QUOTED, RangeEx, RANGEEX_END, RANGEEX_GOOP, RANGEEX_QUOTED, RANGEEX_START, RANGEEX_TO, RangeIn, RANGEIN_END, RANGEIN_GOOP, RANGEIN_QUOTED, RANGEIN_START, RANGEIN_TO, RPAREN, STAR, TERM, tokenImage, WILDTERM

Method Summary

protected Query	getFieldQuery(String field, String queryText) Gets the fieldQuery attribute of the FieldExpansionQueryParser object
Query	parse(String query) Parses a query which searches on the fields specified.
static Query	parse(String query, Analyzer analyzer, String[] expansionFields, String[] boostingFields, Map boostValues, VirtualSearchFieldMapper mappedFields, QueryParser.Operator defaultOperator) Parses the query text to create an expanded Lucene Query.
Query	parse(String query, String field) Parses a query string, returning a Query.
static void	setDebug(boolean db) Sets the debug attribute of the FieldQueryParser object

Methods inherited from class org.apache.lucene.queryParser.QueryParser

addClause, Clause, Conjunction, disable_tracing, enable_tracing, escape, generateParseException, getAllowLeadingWildcard, getAnalyzer, getBooleanQuery, getBooleanQuery, getDateResolution, getDefaultOperator, getEnablePositionIncrements, getField, getFieldQuery, getFuzzyMinSim, getFuzzyPrefixLength, getFuzzyQuery, getLocale, getLowercaseExpandedTerms, getMultiTermRewriteMethod, getNextToken, getPhraseSlop, getPrefixQuery, getRangeCollator, getRangeQuery, getToken, getWildcardQuery, main, Modifiers, newBooleanClause, newBooleanQuery, newFuzzyQuery, newMatchAllDocsQuery, newMultiPhraseQuery, newPhraseQuery, newPrefixQuery, newRangeQuery, newTermQuery, newWildcardQuery, Query, ReInit, ReInit, setAllowLeadingWildcard, setDateResolution, setDateResolution, setDefaultOperator, setEnablePositionIncrements, setFuzzyMinSim, setFuzzyPrefixLength, setLocale, setLowercaseExpandedTerms, setMultiTermRewriteMethod, setPhraseSlop, setRangeCollator, Term, TopLevelQuery

Methods inherited from class java.lang.Object

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

Method Detail

parse

public static Query parse(String query,
                          Analyzer analyzer,
                          String[] expansionFields,
                          String[] boostingFields,
                          Map boostValues,
                          VirtualSearchFieldMapper mappedFields,
                          QueryParser.Operator defaultOperator)
                   throws ParseException

Parses the query text to create an expanded Lucene Query. Default text is searched in the given expansion fields with boosting applied for the given boosting fields. At least one field must be supplied in the expansion fields in order to form a valid query.

If n fields are specified, this effectively constructs:

 
 (field1:query) (field2:query) (field3:query)...(fieldn:query)  

Parameters:

query - The query text

analyzer - The Analyzer to user

expansionFields - Fields to search in for default text, which must contain at least one field

boostingFields - Fields to boost terms found in the default text, or null

boostValues - A Map of boosting values corresponding the the boostingFields - Map of String/Float pairs, or null

mappedFields - Field/term mappings to apply, or null

defaultOperator - Default AND or OR operator

Returns:

A Query

Throws:

ParseException - If unable to parse the query

parse

public Query parse(String query)
            throws ParseException

Parses a query which searches on the fields specified. This expands the query so that multiple fields are searched for the default text, and boosting is applied for the given boosting fields.

If n fields are specified, this effectively constructs:

 
 (field1:query) (field2:query) (field3:query)...(fieldn:query)  

Overrides:

parse in class QueryParser

Parameters:

query - Query string to parse

Returns:

A Query or null if none

Throws:

ParseException - if query parsing fails

TokenMgrError - if query parsing fails

parse

public Query parse(String query,
                   String field)
            throws ParseException

Parses a query string, returning a Query. Same as the QueryParser parse method but adds the ability to specify the default field rather than using the one initialized in the constructor.

Parameters:

query - the query string to be parsed.

field - the default field for this query.

Returns:

A Query Object.

Throws:

ParseException - if the parsing fails

getFieldQuery

protected Query getFieldQuery(String field,
                              String queryText)
                       throws ParseException

Gets the fieldQuery attribute of the FieldExpansionQueryParser object

Overrides:

getFieldQuery in class QueryParser

Parameters:

field - The field being processed

queryText - The text in the field

Returns:

The fieldQuery value

Throws:

ParseException - If error

setDebug

public static void setDebug(boolean db)

Sets the debug attribute of the FieldQueryParser object

Parameters:

db - The new debug value