org.mmbase.storage.search.legacy
Class ConstraintParser

java.lang.Object
  org.mmbase.storage.search.legacy.ConstraintParser

public class ConstraintParser

extends java.lang.Object

Parser, tries to parse a SQL-search-condition for a query to a Constraint object.

This class is provided for the sole purpose of alignment of old code with the new SearchQuery framework, and should not be called by new code.

A SQL-search-condition can be one of these forms:

• [NOT] (SQL-search-condition)
• [NOT] simple-SQL-search-condition
• SQL-search-condition AND SQL-search-condition
• SQL-search-condition OR SQL-search-condition

A simple-SQL-search-condition string can be of one of these forms:

• field [NOT] LIKE value
• UPPER(field) [NOT] LIKE value
• LOWER(field) [NOT] LIKE value
• field IS [NOT] NULL
• field [NOT] IN (value1, value2, ..)
• field [NOT] BETWEEN value1 AND value2
• UPPER(field) [NOT] BETWEEN value1 AND value2
• LOWER(field) [NOT] BETWEEN value1 AND value2
• field = value
• field = field2
• UPPER(field) = value
• LOWER(field) = value
• field == value
• field == field2
• field <= value
• field <= field2
• field < value
• field < field2
• field >= value
• field >= field2
• field > value
• field > field2
• field <> value
• field <> field2
• field != value
• field != field2
• string-search-condition

A field can be one of these forms:

• stepalias.fieldname
• fieldname (only when the query has just one step).

A value can be one of these forms:

• string between single quotes for string fields, example: 'A string value'
• numerical value for numerical fields, example: 123.456
• numerical value between single quotes for numerical fields, example" '123.456'

A string-search-condition can be of this form:

• StringSearch(field,PHRASE|PROXIMITY|WORD, FUZZY|LITERAL|SYNONYM, searchterms, casesensitive) [.set(FUZZINESS,fuzziness)] [.set(PROXIMITY_LIMIT,proximity)]

searchterms can be of one of these forms:

• 'term1'
• "term1"
• 'term1 term2'
• "term1 term2"
• etc...

casesensitive can be of one on these forms:

• true
• false

fuzziness must be a float value between 0.0 and 1.0, proximity must be a int value > 0

See StringSearchConstraint for more info on string-search constraints.

A search condition that is not of one of these forms will be converted to a LegacyConstraint, i.e. in that case the search condition string will not be interpreted, but instead be used "as-is". Each time this occurs is logged with priority service to category org.mmbase.storage.search.legacyConstraintParser.fallback.

Since:

MMBase-1.7

Version:

$Id: ConstraintParser.java,v 1.20.2.1 2004/07/09 14:03:47 michiel Exp $

Author:

Rob van Maris

Constructor Summary

ConstraintParser(SearchQuery query)
Creates a new instance of ConstraintParser

Method Summary

static StepField	getField(java.lang.String token, java.util.List steps) Creates StepField corresponding to field indicated by token, of one of the specified steps.
Constraint	toConstraint(java.lang.String sqlConstraint) Parses SQL-search-condition, and produces a corresponding Constraint object.

Methods inherited from class java.lang.Object

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

Constructor Detail

ConstraintParser

public ConstraintParser(SearchQuery query)

Creates a new instance of ConstraintParser

Method Detail

getField

public static StepField getField(java.lang.String token,
                                 java.util.List steps)

Creates StepField corresponding to field indicated by token, of one of the specified steps.

A field can be one of these forms:

• stepalias.fieldname
• [stepalias.fieldname]
• fieldname (only when just one step is specified).
• [fieldname] (only when just one step is specified).

Parameters:

token - The token.

steps - The steps.

Returns:

The field.

toConstraint

public Constraint toConstraint(java.lang.String sqlConstraint)

Parses SQL-search-condition, and produces a corresponding Constraint object.

See above for the format of a SQL-search-condition.

Parameters:

sqlConstraint - The non-null SQL constraint string.

Returns:

The constraint.