護士名單修改

Question

嗨，我是Optaplanner的新成員，我正在努力調整護士名單，以便爲機場代辦託管代理服務。我創建了A FlightAssignment，其中僱員被分配到航班。

The Employee是PlanningVariable。

FlightAssignment是PlanningEntity。

的CheckinRoster是PlanningEntityCollectionProperty

請幫助我，當我運行CheckinRosteringApp我得到這個錯誤：

2017-03-03 16:35:47,574 [main] INFO CloudBalance 1 has 9 flights and 15 employees with a search space of 10^14. 
Exception in thread "main" java.lang.IllegalArgumentException: The solutionClass (class org.optaplanner.examples.handler.domain.CheckinRoster)'s entityCollectionProperty (flightAssignmentList) should never return null. 
    at org.optaplanner.core.impl.domain.solution.descriptor.SolutionDescriptor.extractEntityCollection(SolutionDescriptor.java:657) 
    at org.optaplanner.core.impl.domain.solution.descriptor.SolutionDescriptor.getEntityCount(SolutionDescriptor.java:516) 
    at org.optaplanner.core.impl.domain.solution.cloner.FieldAccessingSolutionCloner$FieldAccessingSolutionClonerRun.cloneSolution(FieldAccessingSolutionCloner.java:201) 
    at org.optaplanner.core.impl.domain.solution.cloner.FieldAccessingSolutionCloner.cloneSolution(FieldAccessingSolutionCloner.java:72) 
    at org.optaplanner.core.impl.score.director.AbstractScoreDirector.cloneSolution(AbstractScoreDirector.java:142) 
    at org.optaplanner.core.impl.solver.scope.DefaultSolverScope.setWorkingSolutionFromBestSolution(DefaultSolverScope.java:198) 
    at org.optaplanner.core.impl.solver.DefaultSolver.solvingStarted(DefaultSolver.java:196) 
    at org.optaplanner.core.impl.solver.DefaultSolver.solve(DefaultSolver.java:175) 
    at org.optaplanner.examples.handler.app.CheckinRosteringApp.main(CheckinRosteringApp.java:30) 

如果我初始化flightAssignmentList錯誤消失，但解決方案是空的。

2017-03-04 18:31:43,691 [main] INFO CheckinRoster 1 has 8 flights and 20 employees with a search space of 10^18. 
2017-03-04 18:31:44,061 [main] INFO Solving started: time spent (350), best score (-25hard/0soft), environment mode (REPRODUCIBLE), random (JDK with seed 0). 
2017-03-04 18:31:44,078 [main] INFO Construction Heuristic phase (0) ended: step total (0), time spent (369), best score (-25hard/0soft). 
2017-03-04 18:31:44,090 [main] WARN  No doable selected move at step index (0), time spent (382). Terminating phase early. 
2017-03-04 18:31:44,091 [main] INFO Local Search phase (1) ended: step total (0), time spent (383), best score (-25hard/0soft). 
2017-03-04 18:31:44,091 [main] INFO Solving ended: time spent (383), best score (-25hard/0soft), average calculate count per second (7), environment mode (REPRODUCIBLE). 
[...] 

我在xml配置文件中出錯了嗎？我用nurserostering中的那個刪除unionMoveSelector塊，希望在optaplanner中尋找解決方案。

這是checkinRosteringSolverConfig.xml

<?xml version="1.0" encoding="UTF-8"?> 
<solver> 
    <!--<environmentMode>FAST_ASSERT</environmentMode>--> 
    <solutionClass>org.optaplanner.examples.handler.domain.CheckinRoster</solutionClass> 
    <entityClass>org.optaplanner.examples.handler.domain.FlightAssignment</entityClass> 

    <scoreDirectorFactory> 
    <scoreDefinitionType>HARD_SOFT</scoreDefinitionType> 
    <scoreDrl>org/optaplanner/examples/handler/solver/checkinRosteringScoreRules.drl</scoreDrl> 
    </scoreDirectorFactory> 

    <termination> 
    <!-- 
     Official benchmark secondsSpentLimit allowed on: 
     - ge0ffrey's main pc: sprint 11, medium 700, long 42000 
    --> 
    <secondsSpentLimit>700</secondsSpentLimit> 
    <!--<bestScoreLimit>-0hard/-999999soft</bestScoreLimit>--> 
    </termination> 
    <constructionHeuristic> 
    <constructionHeuristicType>WEAKEST_FIT</constructionHeuristicType> 
    </constructionHeuristic> 
    <localSearch> 
    <acceptor> 
     <entityTabuSize>7</entityTabuSize> 
    </acceptor> 
    <forager> 
     <acceptedCountLimit>800</acceptedCountLimit> 
    </forager> 
    </localSearch> 
</solver> 

這是checkingRosteringScoreRules.drl

/* 
* Copyright 2010 Red Hat, Inc. and/or its affiliates. 
* 
* Licensed under the Apache License, Version 2.0 (the "License"); 
* you may not use this file except in compliance with the License. 
* You may obtain a copy of the License at 
* 
*  http://www.apache.org/licenses/LICENSE-2.0 
* 
* Unless required by applicable law or agreed to in writing, software 
* distributed under the License is distributed on an "AS IS" BASIS, 
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
* See the License for the specific language governing permissions and 
* limitations under the License. 
*/ 

package org.optaplanner.examples.handler.solver; 
    dialect "java" 

import org.optaplanner.core.api.score.buildin.hardsoft.HardSoftScoreHolder; 


import org.optaplanner.examples.handler.domain.Employee; 
import org.optaplanner.examples.handler.domain.Flight; 
import org.optaplanner.examples.handler.domain.FlightAssignment; 
import org.optaplanner.examples.handler.domain.CheckinRoster; 

global HardSoftScoreHolder scoreHolder; 

// ############################################################################ 
// Hard constraints 
// ############################################################################ 

// This rule is build in 
// All demanded shifts must be assigned to a nurse 
rule "requiredEmployeeSizePerShift" 
    when 
     $flight : Flight(minimumEmployeesNumber > 0, $minimumEmployeesNumber : minimumEmployeesNumber) 
     $totalEmployeeNumber : Number(intValue <= $minimumEmployeesNumber) from accumulate(
       $assignment : FlightAssignment(flight == $flight), 
       count($assignment) 
     ) 
    then 
     scoreHolder.addHardConstraintMatch(kcontext, - Math.abs($minimumEmployeesNumber - $totalEmployeeNumber.intValue())); 
end 

//a nurse can only work on no clashing flights 
//TODO 


//TODO 

// a nurse can only work one shift per day, i.e. no two shift can be assigned to the same nurse on a day. 
//rule "oneShiftPerDay" 
// when 
//  ShiftAssignment($leftId : id, $employee : employee, $shiftDate : shiftDate, employee != null) 
//  ShiftAssignment(employee == $employee, shiftDate == $shiftDate, id > $leftId) 
// then 
//  scoreHolder.addHardConstraintMatch(kcontext, -1); 
//end 

// ############################################################################ 
// Soft constraints 
// ############################################################################ 

rule "employeeCost" 
    when 
     $employee : Employee($income : income) 
     exists FlightAssignment(employee == $employee) 
    then 
     scoreHolder.addSoftConstraintMatch(kcontext, - $income); 
end 

Answer 1

Exception in thread "main" java.lang.IllegalArgumentException: The solutionClass (class org.optaplanner.examples.handler.domain.CheckinRoster)'s entityCollectionProperty (flightAssignmentList) should never return null.

檢查方法CheckinRoster.getFlightAssignmentList()。對於那個數據集，它顯然返回null。