Package org.optaplanner.core.api.domain.variable

Annotation Type PlanningListVariable

  • @Target({METHOD,FIELD})
@Retention(RUNTIME)
public @interface PlanningListVariable
    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. The type of the PlanningListVariable annotated bean property (or a field) must be List.

    List variable

    A planning entity's property annotated with @PlanningListVariable is referred to as a list variable. The way solver optimizes a list variable is by adding, removing, or changing order of elements in the List object held by the list variable.

    Disjoint lists

    Furthermore, the current implementation works under the assumption that the list variables of all entity instances are "disjoint lists":

    • List means that the order of elements inside a list planning variable is significant.
    • Disjoint means that any given pair of entities have no common elements in their list variables. In other words, each element from the list variable's value range appears in exactly one entity's list variable.

    This makes sense for common use cases, for example the Vehicle Routing Problem or Task Assigning. In both cases the order in which customers are visited and tasks are being worked on matters. Also, each customer must be visited once and each task must be completed by exactly one employee.

    Overconstrained planning is currently not supported for list variables.

    • Element Detail

      • valueRangeProviderRefs

        String[] valueRangeProviderRefs
        Default:
        {}