Package org.springframework.ai.vectorstore.filter

Class FilterHelper

java.lang.Object

org.springframework.ai.vectorstore.filter.FilterHelper

public class FilterHelper
extends Object

Helper class providing various boolean transformation.

Author:

Christian Tzolov

Method Summary

Modifier and Type	Method	Description
static void	expandIn(Filter.Expression exp, StringBuilder context, FilterExpressionConverter filterExpressionConverter)	Expands the IN into a semantically equivalent boolean expressions of ORs of EQs.
static void	expandNin(Filter.Expression exp, StringBuilder context, FilterExpressionConverter filterExpressionConverter)	Expands the NIN (e.g.
static Filter.Operand	negate(Filter.Operand operand)	Transforms the input expression into a semantically equivalent one with negation operators propagated thought the expression tree by following the negation rules:

Methods inherited from class java.lang.Object

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

Method Details

negate

public static Filter.Operand negate(Filter.Operand operand)

Transforms the input expression into a semantically equivalent one with negation operators propagated thought the expression tree by following the negation rules:

        NOT(NOT(a)) = a

        NOT(a AND b) = NOT(a) OR NOT(b)
        NOT(a OR b) = NOT(a) AND NOT(b)

        NOT(a EQ b) = a NE b
        NOT(a NE b) = a EQ b

        NOT(a GT b) = a LTE b
        NOT(a GTE b) = a LT b

        NOT(a LT b) = a GTE b
        NOT(a LTE b) = a GT b

        NOT(a IN [...]) = a NIN [...]
        NOT(a NIN [...]) = a IN [...]
 

Parameters:

operand - Filter expression to negate.

Returns:

Returns an negation of the input expression.

expandIn

public static void expandIn(Filter.Expression exp,
 StringBuilder context,
 FilterExpressionConverter filterExpressionConverter)

Expands the IN into a semantically equivalent boolean expressions of ORs of EQs. Useful for providers that don't provide native IN support. For example the

 foo IN ["bar1", "bar2", "bar3"]
 

expression is equivalent to

 foo == "bar1" || foo == "bar2" || foo == "bar3" (e.g. OR(foo EQ "bar1" OR(foo EQ "bar2" OR(foo EQ "bar3")))
 

Parameters:

exp - input IN expression.

context - Output native expression.

filterExpressionConverter - FilterExpressionConverter used to compose the OR and EQ expanded expressions.

expandNin

public static void expandNin(Filter.Expression exp,
 StringBuilder context,
 FilterExpressionConverter filterExpressionConverter)

Expands the NIN (e.g. NOT IN) into a semantically equivalent boolean expressions of ANDs of NEs. Useful for providers that don't provide native NIN support.
For example the

 foo NIN ["bar1", "bar2", "bar3"] (or foo NOT IN ["bar1", "bar2", "bar3"])
 

express is equivalent to

 foo != "bar1" && foo != "bar2" && foo != "bar3" (e.g. AND(foo NE "bar1" AND( foo NE "bar2" OR(foo NE "bar3"))) )
 

Parameters:

exp - input NIN expression.

context - Output native expression.

filterExpressionConverter - FilterExpressionConverter used to compose the AND and NE expanded expressions.