org.apache.lucene.queryParser

Class QueryParser

Implemented Interfaces:
QueryParserConstants
Known Direct Subclasses:
AnalyzingQueryParser, MultiFieldQueryParser

public class QueryParser
extends Object
implements QueryParserConstants

This class is generated by JavaCC. The most important method is parse(String). The syntax for query strings is as follows: A Query is a series of clauses. A clause may be prefixed by: A clause may be either: Thus, in BNF, the query grammar is:
   Query  ::= ( Clause )*
   Clause ::= ["+", "-"] [<TERM> ":"] ( <TERM> | "(" Query ")" )
 

Examples of appropriately formatted queries can be found in the query syntax documentation.

In RangeQuerys, QueryParser tries to detect date values, e.g. date:[6/1/2005 TO 6/4/2005] produces a range query that searches for "date" fields between 2005-06-01 and 2005-06-04. Note that the format of the accpeted input depends on the locale. This feature also assumes that your index uses the DateField class to store dates. If you use a different format (e.g. DateTools) and you still want QueryParser to turn local dates in range queries into valid queries you need to create your own query parser that inherits QueryParser and overwrites getRangeQuery(String,String,String,boolean).

Note that QueryParser is not thread-safe.

Authors:
Brian Goetz
Peter Halacsy
Tatu Saloranta

Nested Class Summary

static class
QueryParser.Operator
The default operator for parsing queries.

Field Summary

static QueryParser.Operator
AND_OPERATOR
Alternative form of QueryParser.Operator.AND
static int
DEFAULT_OPERATOR_AND
Deprecated. use AND_OPERATOR instead
static int
DEFAULT_OPERATOR_OR
Deprecated. use OR_OPERATOR instead
static QueryParser.Operator
OR_OPERATOR
Alternative form of QueryParser.Operator.OR
Token
jj_nt
boolean
lookingAhead
Token
token
QueryParserTokenManager
token_source

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

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

Constructor Summary

QueryParser(String f, Analyzer a)
Constructs a query parser.
QueryParser(CharStream stream)
QueryParser(QueryParserTokenManager tm)

Method Summary

Query
Clause(String field)
int
Conjunction()
int
Modifiers()
Query
Query(String field)
void
ReInit(CharStream stream)
void
ReInit(QueryParserTokenManager tm)
Query
Term(String field)
protected void
addClause(Vector clauses, int conj, int mods, Query q)
void
disable_tracing()
void
enable_tracing()
static String
escape(String s)
Returns a String where those characters that QueryParser expects to be escaped are escaped by a preceding \.
ParseException
generateParseException()
Analyzer
getAnalyzer()
protected Query
getBooleanQuery(Vector clauses)
Factory method for generating query, given a set of clauses.
protected Query
getBooleanQuery(Vector clauses, boolean disableCoord)
Factory method for generating query, given a set of clauses.
QueryParser.Operator
getDefaultOperator()
Gets implicit operator setting, which will be either AND_OPERATOR or OR_OPERATOR.
String
getField()
protected Query
getFieldQuery(String field, String queryText)
protected Query
getFieldQuery(String field, String queryText, int slop)
Base implementation delegates to getFieldQuery(String,String).
protected Query
getFieldQuery(String field, Analyzer analyzer, String queryText)
Deprecated. use getFieldQuery(String,String)
protected Query
getFieldQuery(String field, Analyzer analyzer, String queryText, int slop)
Deprecated. use getFieldQuery(String,String,int)
float
getFuzzyMinSim()
Get the minimal similarity for fuzzy queries.
int
getFuzzyPrefixLength()
Get the prefix length for fuzzy queries.
protected Query
getFuzzyQuery(String field, String termStr)
Deprecated. use getFuzzyQuery(String,String,float)
protected Query
getFuzzyQuery(String field, String termStr, float minSimilarity)
Factory method for generating a query (similar to getWildcardQuery(String,String)).
Locale
getLocale()
Returns current locale, allowing access by subclasses.
boolean
getLowercaseExpandedTerms()
boolean
getLowercaseWildcardTerms()
Deprecated. use getLowercaseExpandedTerms() instead
Token
getNextToken()
int
getOperator()
Deprecated. use getDefaultOperator() instead
int
getPhraseSlop()
Gets the default slop for phrases.
protected Query
getPrefixQuery(String field, String termStr)
Factory method for generating a query (similar to getWildcardQuery(String,String)).
protected Query
getRangeQuery(String field, String part1, String part2, boolean inclusive)
protected Query
getRangeQuery(String field, Analyzer analyzer, String part1, String part2, boolean inclusive)
Deprecated. use getRangeQuery(String,String,String,boolean)
Token
getToken(int index)
protected Query
getWildcardQuery(String field, String termStr)
Factory method for generating a query.
static void
main(String[] args)
Command line tool to test QueryParser, using SimpleAnalyzer.
Query
parse(String query)
Parses a query string, returning a Query.
static Query
parse(String query, String field, Analyzer analyzer)
Deprecated. Use an instance of QueryParser and the parse(String) method instead.
void
setDefaultOperator(QueryParser.Operator op)
Sets the boolean operator of the QueryParser.
void
setFuzzyMinSim(float fuzzyMinSim)
Set the minimum similarity for fuzzy queries.
void
setFuzzyPrefixLength(int fuzzyPrefixLength)
Set the prefix length for fuzzy queries.
void
setLocale(Locale locale)
Set locale used by date range parsing.
void
setLowercaseExpandedTerms(boolean lowercaseExpandedTerms)
Whether terms of wildcard, prefix, fuzzy and range queries are to be automatically lower-cased or not.
void
setLowercaseWildcardTerms(boolean lowercaseExpandedTerms)
Deprecated. use setLowercaseExpandedTerms(boolean) instead
void
setOperator(int op)
Deprecated. use setDefaultOperator(QueryParser.Operator) instead
void
setPhraseSlop(int phraseSlop)
Sets the default slop for phrases.

Field Details

AND_OPERATOR

public static final QueryParser.Operator AND_OPERATOR
Alternative form of QueryParser.Operator.AND

DEFAULT_OPERATOR_AND

public static final int DEFAULT_OPERATOR_AND

Deprecated. use AND_OPERATOR instead

Field Value:
1

DEFAULT_OPERATOR_OR

public static final int DEFAULT_OPERATOR_OR

Deprecated. use OR_OPERATOR instead

Field Value:
0

OR_OPERATOR

public static final QueryParser.Operator OR_OPERATOR
Alternative form of QueryParser.Operator.OR

jj_nt

public Token jj_nt

lookingAhead

public boolean lookingAhead

token

public Token token

token_source

public QueryParserTokenManager token_source

Constructor Details

QueryParser

public QueryParser(String f,
                   Analyzer a)
Constructs a query parser.
Parameters:
f - the default field for query terms.
a - used to find terms in the query text.

QueryParser

public QueryParser(CharStream stream)

QueryParser

public QueryParser(QueryParserTokenManager tm)

Method Details

Clause

public final Query Clause(String field)
            throws ParseException

Conjunction

public final int Conjunction()
            throws ParseException

Modifiers

public final int Modifiers()
            throws ParseException

Query

public final Query Query(String field)
            throws ParseException

ReInit

public void ReInit(CharStream stream)

ReInit

public void ReInit(QueryParserTokenManager tm)

Term

public final Query Term(String field)
            throws ParseException

addClause

protected void addClause(Vector clauses,
                         int conj,
                         int mods,
                         Query q)

disable_tracing

public final void disable_tracing()

enable_tracing

public final void enable_tracing()

escape

public static String escape(String s)
Returns a String where those characters that QueryParser expects to be escaped are escaped by a preceding \.

generateParseException

public ParseException generateParseException()

getAnalyzer

public Analyzer getAnalyzer()
Returns:
Returns the analyzer.

getBooleanQuery

protected Query getBooleanQuery(Vector clauses)
            throws ParseException
Factory method for generating query, given a set of clauses. By default creates a boolean query composed of clauses passed in. Can be overridden by extending classes, to modify query being returned.
Parameters:
clauses - Vector that contains BooleanClause instances to join.
Returns:
Resulting Query object.
Throws:
ParseException - throw in overridden method to disallow

getBooleanQuery

protected Query getBooleanQuery(Vector clauses,
                                boolean disableCoord)
            throws ParseException
Factory method for generating query, given a set of clauses. By default creates a boolean query composed of clauses passed in. Can be overridden by extending classes, to modify query being returned.
Parameters:
clauses - Vector that contains BooleanClause instances to join.
disableCoord - true if coord scoring should be disabled.
Returns:
Resulting Query object.
Throws:
ParseException - throw in overridden method to disallow

getDefaultOperator

public QueryParser.Operator getDefaultOperator()
Gets implicit operator setting, which will be either AND_OPERATOR or OR_OPERATOR.

getField

public String getField()
Returns:
Returns the field.

getFieldQuery

protected Query getFieldQuery(String field,
                              String queryText)
            throws ParseException
Throws:
ParseException - throw in overridden method to disallow

getFieldQuery

protected Query getFieldQuery(String field,
                              String queryText,
                              int slop)
            throws ParseException
Base implementation delegates to getFieldQuery(String,String). This method may be overridden, for example, to return a SpanNearQuery instead of a PhraseQuery.
Throws:
ParseException - throw in overridden method to disallow

getFieldQuery

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

Deprecated. use getFieldQuery(String,String)

Note that parameter analyzer is ignored. Calls inside the parser always use class member analyzer.
Throws:
ParseException - throw in overridden method to disallow

getFieldQuery

protected Query getFieldQuery(String field,
                              Analyzer analyzer,
                              String queryText,
                              int slop)
            throws ParseException

Deprecated. use getFieldQuery(String,String,int)

Note that parameter analyzer is ignored. Calls inside the parser always use class member analyzer.
Throws:
ParseException - throw in overridden method to disallow

getFuzzyMinSim

public float getFuzzyMinSim()
Get the minimal similarity for fuzzy queries.

getFuzzyPrefixLength

public int getFuzzyPrefixLength()
Get the prefix length for fuzzy queries.
Returns:
Returns the fuzzyPrefixLength.

getFuzzyQuery

protected Query getFuzzyQuery(String field,
                              String termStr)
            throws ParseException

Deprecated. use getFuzzyQuery(String,String,float)


getFuzzyQuery

protected Query getFuzzyQuery(String field,
                              String termStr,
                              float minSimilarity)
            throws ParseException
Factory method for generating a query (similar to getWildcardQuery(String,String)). Called when parser parses an input term token that has the fuzzy suffix (~) appended.
Parameters:
field - Name of the field query will use.
termStr - Term token to use for building term for the query
Returns:
Resulting Query built for the term
Throws:
ParseException - throw in overridden method to disallow

getLocale

public Locale getLocale()
Returns current locale, allowing access by subclasses.

getLowercaseExpandedTerms

public boolean getLowercaseExpandedTerms()

getLowercaseWildcardTerms

public boolean getLowercaseWildcardTerms()

Deprecated. use getLowercaseExpandedTerms() instead


getNextToken

public final Token getNextToken()

getOperator

public int getOperator()

Deprecated. use getDefaultOperator() instead

Gets implicit operator setting, which will be either DEFAULT_OPERATOR_AND or DEFAULT_OPERATOR_OR.

getPhraseSlop

public int getPhraseSlop()
Gets the default slop for phrases.

getPrefixQuery

protected Query getPrefixQuery(String field,
                               String termStr)
            throws ParseException
Factory method for generating a query (similar to getWildcardQuery(String,String)). Called when parser parses an input term token that uses prefix notation; that is, contains a single '*' wildcard character as its last character. Since this is a special case of generic wildcard term, and such a query can be optimized easily, this usually results in a different query object.

Depending on settings, a prefix term may be lower-cased automatically. It will not go through the default Analyzer, however, since normal Analyzers are unlikely to work properly with wildcard templates.

Can be overridden by extending classes, to provide custom handling for wild card queries, which may be necessary due to missing analyzer calls.

Parameters:
field - Name of the field query will use.
termStr - Term token to use for building term for the query (without trailing '*' character!)
Returns:
Resulting Query built for the term
Throws:
ParseException - throw in overridden method to disallow

getRangeQuery

protected Query getRangeQuery(String field,
                              String part1,
                              String part2,
                              boolean inclusive)
            throws ParseException
Throws:
ParseException - throw in overridden method to disallow

getRangeQuery

protected Query getRangeQuery(String field,
                              Analyzer analyzer,
                              String part1,
                              String part2,
                              boolean inclusive)
            throws ParseException

Deprecated. use getRangeQuery(String,String,String,boolean)

Note that parameter analyzer is ignored. Calls inside the parser always use class member analyzer.
Throws:
ParseException - throw in overridden method to disallow

getToken

public final Token getToken(int index)

getWildcardQuery

protected Query getWildcardQuery(String field,
                                 String termStr)
            throws ParseException
Factory method for generating a query. Called when parser parses an input term token that contains one or more wildcard characters (? and *), but is not a prefix term token (one that has just a single * character at the end)

Depending on settings, prefix term may be lower-cased automatically. It will not go through the default Analyzer, however, since normal Analyzers are unlikely to work properly with wildcard templates.

Can be overridden by extending classes, to provide custom handling for wildcard queries, which may be necessary due to missing analyzer calls.

Parameters:
field - Name of the field query will use.
termStr - Term token that contains one or more wild card characters (? or *), but is not simple prefix term
Returns:
Resulting Query built for the term
Throws:
ParseException - throw in overridden method to disallow

main

public static void main(String[] args)
            throws Exception
Command line tool to test QueryParser, using SimpleAnalyzer. Usage:
java org.apache.lucene.queryParser.QueryParser <input>

parse

public Query parse(String query)
            throws ParseException
Parses a query string, returning a Query.
Parameters:
query - the query string to be parsed.
Throws:
ParseException - if the parsing fails

parse

public static Query parse(String query,
                          String field,
                          Analyzer analyzer)
            throws ParseException

Deprecated. Use an instance of QueryParser and the parse(String) method instead.

Parses a query string, returning a Query.
Parameters:
query - the query string to be parsed.
field - the default field for query terms.
analyzer - used to find terms in the query text.
Throws:
ParseException - if the parsing fails

setDefaultOperator

public void setDefaultOperator(QueryParser.Operator op)
Sets the boolean operator of the QueryParser. In default mode (OR_OPERATOR) terms without any modifiers are considered optional: for example capital of Hungary is equal to capital OR of OR Hungary.
In AND_OPERATOR mode terms are considered to be in conjuction: the above mentioned query is parsed as capital AND of AND Hungary

setFuzzyMinSim

public void setFuzzyMinSim(float fuzzyMinSim)
Set the minimum similarity for fuzzy queries. Default is 0.5f.

setFuzzyPrefixLength

public void setFuzzyPrefixLength(int fuzzyPrefixLength)
Set the prefix length for fuzzy queries. Default is 0.
Parameters:
fuzzyPrefixLength - The fuzzyPrefixLength to set.

setLocale

public void setLocale(Locale locale)
Set locale used by date range parsing.

setLowercaseExpandedTerms

public void setLowercaseExpandedTerms(boolean lowercaseExpandedTerms)
Whether terms of wildcard, prefix, fuzzy and range queries are to be automatically lower-cased or not. Default is true.

setLowercaseWildcardTerms

public void setLowercaseWildcardTerms(boolean lowercaseExpandedTerms)

Deprecated. use setLowercaseExpandedTerms(boolean) instead

Whether terms of wildcard, prefix, fuzzy and range queries are to be automatically lower-cased or not. Default is true.

setOperator

public void setOperator(int op)

Deprecated. use setDefaultOperator(QueryParser.Operator) instead

Sets the boolean operator of the QueryParser. In default mode (DEFAULT_OPERATOR_OR) terms without any modifiers are considered optional: for example capital of Hungary is equal to capital OR of OR Hungary.
In DEFAULT_OPERATOR_AND terms are considered to be in conjuction: the above mentioned query is parsed as capital AND of AND Hungary

setPhraseSlop

public void setPhraseSlop(int phraseSlop)
Sets the default slop for phrases. If zero, then exact phrase matches are required. Default value is zero.

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