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

Annotation Interface ShadowSources

@Target(METHOD) @Retention(RUNTIME) public @interface ShadowSources
Specifies the paths to variables that a method referenced by ShadowVariable.supplierName() uses to compute the value of a ShadowVariable.

  • Required Element Summary

    Required Elements
    Modifier and Type
    Required Element
    Description
    String[]
    value
    The paths to variables the method uses to compute the value of a supplier variable.

  • Element Details

    • value

      String[] value
      The paths to variables the method uses to compute the value of a supplier variable.

      Each path is a String that is one of the following three forms:

      • "variableName", for referring any variable on the same planning entity.
      • A list of names seperated by ".", such as "variableOrFact.fact.entity.supplierVariable", for referencing a supplier variable accessible from the planning entity. The first property may be a fact or any non-supplier variable; the remaining properties before the end must be facts, and the final property must be a supplier variable. For the path "a.b", it refers to the supplier variable "b" on the property/variable "a" of the planning entity. In general, if you access a variable in your method using a chain like a.b.c, that chain should be included as a source.
      • A list of names seperated by ".", followed by a name suffix by "[].", followed by either of the forms above. For example, "group[].previous". In this case, "group" is a Collection on the planning entity, and the annotated method uses the "previous" variable of each element in the collection. The collection must not change during solving and may be null.
      For example, for this method 
       
 @InverseRelationShadowVariable
 Entity entity;

 @PreviousElementShadowVariable
 Value previous;

 @ShadowVariable(supplierName="startTimeSupplier")
 LocalDateTime startTime;

 @ShadowVariable(supplierName="endTimeSupplier")
 LocalDateTime endTime;

 Collection<Value> dependencies;

 &#64;ShadowSources("previous.endTime", "entity", "dependencies[].endTime")
 public LocalDateTime startTimeSupplier() {
     LocalDateTime readyTime = null;
     if (previous != null) {
         readyTime = previous.endTime;
     } else if (entity != null) {
         readyTime = entity.startTime;
     } else {
         return null;
     }
     if (dependencies != null) {
         for (var dependency : dependencies) {
             if (dependency.endTime == null) {
                 return null;
             }
             readyTime = (readyTime.isBefore(dependency.endTime)? dependency.endTime: readyTime;
         }
     }
     return readyTime;
 }
      The value { "previous.endTime", "entity", "dependencies[].endTime") } is used for ShadowSources since it accesses the end time supplier variable of its previous element variable ("previous.endTime"), a fact on its inverse relation variable ("entity"), and the end time supplier variable on each element in its dependencies ("dependencies[].endTime").

      Returns:
      A non-empty list of variables the supplier method accesses.