org.optaplanner.core.api.domain.variable

Annotation Type PlanningVariable

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

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

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

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
PlanningVariableGraphType	graphType In some use cases, such as Vehicle Routing, planning entities form a specific graph type, as specified by PlanningVariableGraphType.
boolean	nullable A nullable planning variable will automatically add the planning value null to the ValueRangeProvider's range.
Class<? extends SelectionFilter>	reinitializeVariableEntityFilter Construction heuristics only change reinitializable planning variables.
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 it's ValueRangeProvider.id().

Element Detail

valueRangeProviderRefs

public abstract String[] valueRangeProviderRefs

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

There should be at least 1 element in this array.

Returns:

1 (or more) registered ValueRangeProvider.id()

Default:

{}

nullable

public abstract boolean nullable

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

In repeated planning use cases, it's recommended to specify a reinitializeVariableEntityFilter() for every nullable planning variable too.

nullable() true is not compatible with PlanningVariableGraphType.CHAINED true. nullable() true is not compatible with a primitive property type.

Returns:

true if null is a valid value for this planning variable

Default:

false

reinitializeVariableEntityFilter

public abstract Class<? extends SelectionFilter> reinitializeVariableEntityFilter

Construction heuristics only change reinitializable planning variables. Non reinitializable planning variable is ignored by construction heuristics. This is especially useful in repeated planning use cases, in which starting from scratch would waste previous results and time.

If no reinitializeVariableEntityFilter() is specified, the default considers an entity uninitialized for a variable if its value is null (even if nullable() is true).

The method SelectionFilter.accept(ScoreDirector, Object) returns false if the selection entity should be reinitialized for this variable and it returns true if the selection entity should not be reinitialized for this variable

Returns:

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

Default:

org.optaplanner.core.api.domain.variable.PlanningVariable.NullReinitializeVariableEntityFilter.class

graphType

public abstract 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:

org.optaplanner.core.api.domain.variable.PlanningVariableGraphType.NONE

strengthComparatorClass

public abstract 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:

org.optaplanner.core.api.domain.variable.PlanningVariable.NullStrengthComparator.class

strengthWeightFactoryClass

public abstract 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:

org.optaplanner.core.api.domain.variable.PlanningVariable.NullStrengthWeightFactory.class