Package ai.timefold.solver.core.api.domain.variable

Annotation Interface PlanningVariable

@Target({METHOD,FIELD})
@Retention(RUNTIME)
public @interface PlanningVariable

Specifies that a bean property (or a field) can be changed and should be optimized by the optimization algorithms.

The property must be an object type. Primitive types (such as int, double, long) are not allowed.

It is specified on a getter of a java bean property (or directly on a field) of a PlanningEntity class.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	PlanningVariable.NullStrengthComparator	Workaround for annotation limitation in strengthComparatorClass().
static interface	PlanningVariable.NullStrengthWeightFactory	Workaround for annotation limitation in strengthWeightFactoryClass().

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element	Description
boolean	allowsUnassigned	A variable will automatically add the planning value null to the ValueRangeProvider's range.
PlanningVariableGraphType	graphType	In some use cases, such as Vehicle Routing, planning entities form a specific graph type, as specified by PlanningVariableGraphType.
boolean	nullable	Deprecated, for removal: This API element is subject to removal in a future version. Use allowsUnassigned() instead.
Class<? extends Comparator>	strengthComparatorClass	Allows a collection of planning values for this variable to be sorted by strength.
Class<? extends SelectionSorterWeightFactory>	strengthWeightFactoryClass	The SelectionSorterWeightFactory alternative for strengthComparatorClass().
String[]	valueRangeProviderRefs	Any ValueRangeProvider annotation on a PlanningSolution or PlanningEntity will automatically be registered with its ValueRangeProvider.id().

Element Details

valueRangeProviderRefs

String[] valueRangeProviderRefs

Any ValueRangeProvider annotation on a PlanningSolution or PlanningEntity will automatically be registered with its ValueRangeProvider.id().

If no refs are provided, all ValueRangeProviders without an id will be registered, provided their return types match the type of this variable.

Returns:

0 or more registered ValueRangeProvider.id()

Default:

{}

allowsUnassigned

boolean allowsUnassigned

A variable will automatically add the planning value null to the ValueRangeProvider's range.

Allowing unassigned is not compatible with PlanningVariableGraphType.CHAINED true. Allowing unassigned is not compatible with a primitive property type.

Returns:

true if null is a valid value for this planning variable

See Also:

• PlanningListVariable.allowsUnassignedValues()

Default:

false

nullable

@Deprecated(forRemoval=true,
            since="1.8.0")
boolean nullable

Deprecated, for removal: This API element is subject to removal in a future version.

Use allowsUnassigned() instead.

As defined by allowsUnassigned().

Returns:

true if null is a valid value for this planning variable

Default:

false

graphType

PlanningVariableGraphType graphType

In some use cases, such as Vehicle Routing, planning entities form a specific graph type, as specified by PlanningVariableGraphType.

Returns:

never null, defaults to PlanningVariableGraphType.NONE

Default:

NONE

strengthComparatorClass

Class<? extends Comparator> strengthComparatorClass

Allows a collection of planning values for this variable to be sorted by strength. A strengthWeight estimates how strong a planning value is. Some algorithms benefit from planning on weaker planning values first or from focusing on them.

The Comparator should sort in ascending strength. For example: sorting 3 computers on strength based on their RAM capacity: Computer B (1GB RAM), Computer A (2GB RAM), Computer C (7GB RAM),

Do not use together with strengthWeightFactoryClass().

Returns:

PlanningVariable.NullStrengthComparator when it is null (workaround for annotation limitation)

See Also:

• strengthWeightFactoryClass()

Default:

ai.timefold.solver.core.api.domain.variable.PlanningVariable.NullStrengthComparator.class

strengthWeightFactoryClass

Class<? extends SelectionSorterWeightFactory> strengthWeightFactoryClass

The SelectionSorterWeightFactory alternative for strengthComparatorClass().

Do not use together with strengthComparatorClass().

Returns:

PlanningVariable.NullStrengthWeightFactory when it is null (workaround for annotation limitation)

See Also:

• strengthComparatorClass()

Default:

ai.timefold.solver.core.api.domain.variable.PlanningVariable.NullStrengthWeightFactory.class