Question

有地理，数学，历史，艺术，物理5门课程，每门课程分为3节课。例如GeographyA，GeographyB，GeographyC ...

200名学生每人需要在不同的时间段中选择3门课程的3门课程，我们不需要Day变量...

@PlanningEntity
class Lecture {

    Student student  // not null
    Course course  // not null

    // there 3 timeslot, there is no same klass or same timeslot for student
    @PlanningVariable
    Klass Klass      
    @PlanningVariable 
    Integer timesolt   
}

开始演讲

new Lecture(id++, student_1, course_history)
new Lecture(id++, student_1, course_math)
new Lecture(id++, student_1, course_art)

最后，我们需要一个规则，一个学生不应有两个相同的时隙。

rule "student should not have 2 same timeslot"
    when
        $student: Student()
        $timeslotSet: Set() from accumulate (
            Lecture(student == $student, $timeslot: timeslot, timeslot != null), collectSet($timeslot)
        )
    then
        scoreHolder.addHardConstraintMatch(kcontext, -(3 - $timeslotSet.size()) * 17);
end

将引发异常，但

rule "student should not have 2 same timeslot"
    when
        Lecture($id : id, $student: student, $timeslot: timeslot)
        Lecture(id > $id, student == $student, timeslot == $timeslot)
    then
        scoreHolder.addHardConstraintMatch(kcontext, -17); // if 
end

效果很好

为什么??

我已经用Google搜索并阅读了文档，有关“ constraintMatch”的内容较少。对不起我的英语不好

发生了什么“ java.lang.IllegalStateException：constraintMatchTotal无法删除constraintMatch”

0 个答案: