Milestones

A milestone is used to represent achievable targets within the case. It is not associated with any work but rather marks that certain conditions have been reached within the case. As a milestone is a regular plan item definition, a milestone’s completion may be used as entry criteria for other tasks and stages. This way, a milestone can be used to bring logical stages within a case into order.

In XML, a milestone is defined as follows:

<milestone id="theMilestone" name="A Milestone"/>

When referenced in a case plan, a milestone gets completed as soon as its entry criteria are fulfilled. This requires no human interaction. A more complete example of a milestone depending on the completion of a human task is the following:

<definitions>
  <case id="case" name="Case">
    <casePlanModel id="CasePlanModel_1">
      <planItem id="PlanItem_HumanTask" definitionRef="HumanTask_1"/>
      <planItem id="PlanItem_Milestone" definitionRef="Milestone_1">
        <entryCriterion sentryRef="Sentry_1" />
      </planItem>

      <sentry id="Sentry_1">
        <planItemOnPart sourceRef="PlanItem_HumanTask">
          <standardEvent>complete</standardEvent>
        </planItemOnPart>
      </sentry>

      <humanTask id="HumanTask_1" />
      <milestone id="Milestone_1" name="A Milestone" />
    </casePlanModel>
  </case>
</defintions>

In this case, the milestone will complete as soon as as the human task completes.

A milestone cannot have exit criteria.

Checking Milestones

In order to check whether a milestone has occurred, the history service can be used. The following checks the state of a milestone instance:

HistoricCaseActivityInstance milestoneInstance = historyService
  .createHistoricCaseActivityInstanceQuery()
  .caseInstanceId("aCaseInstanceId")
  .caseActivityId("theMilestone")
  .singleResult();

milestoneInstance.isCompleted(); // true if milestone occurred

Camunda Extensions