Drools Planner在创建配置程序时遇到问题：如何调试

我试图从XML配置创建一个解算器。但整个过程都会返回一条毫无意义的神秘错误消息

我该如何解决这个问题？我如何理解这一点来解决类似的问题呢

jesvin@Jesvin-Technovia:~/dev/drools/sudoku$ java App 
Exception in thread "main" java.lang.NullPointerException
    at org.drools.planner.core.domain.solution.SolutionDescriptor.processPropertyAnnotations(SolutionDescriptor.java:69)
    at org.drools.planner.core.domain.solution.SolutionDescriptor.<init>(SolutionDescriptor.java:61)
    at org.drools.planner.config.solver.SolverConfig.buildSolutionDescriptor(SolverConfig.java:197)
    at org.drools.planner.config.solver.SolverConfig.buildSolver(SolverConfig.java:167)
    at org.drools.planner.config.XmlSolverConfigurer.buildSolver(XmlSolverConfigurer.java:103)
    at App.createSolver(App.java:62)
    at App.main(App.java:40)

XML的内容：

<?xml version="1.0" encoding="UTF-8"?>
<solver>
  <environmentMode>DEBUG</environmentMode>

  <solutionClass>domain.Sudoku</solutionClass>
  <planningEntityClass>domain.Digit</planningEntityClass>
  <scoreDrl>score.drl</scoreDrl>
  <scoreDefinition>
    <scoreDefinitionType>SIMPLE</scoreDefinitionType>
  </scoreDefinition>

  <termination>
    <scoreAttained>0</scoreAttained>
  </termination>
  <!--
  <constructionHeuristic>
    <constructionHeuristicType>FIRST_FIT_DECREASING</constructionHeuristicType>
    <constructionHeuristicPickEarlyType>FIRST_LAST_STEP_SCORE_EQUAL_OR_IMPROVING</constructionHeuristicPickEarlyType>
</constructionHeuristic> -->
  <constructionHeuristic>
    <constructionHeuristicType>FIRST_FIT</constructionHeuristicType>

      <moveFactoryClass>solution.RowChangeMoveFactory</moveFactoryClass>
    </selector>
    <acceptor>
      <completeSolutionTabuSize>1000</completeSolutionTabuSize>
    </acceptor>
    <forager>
      <!-- Real world problems require to use of <minimalAcceptedSelection> -->
    </forager>
  </localSearch>
</solver>

调试
域名，数独
域。数字
score.drl
简单的
0
初试
解决方案.RowChangeMoveFactory
1000

5.4.0.Beta1（已发布）中修复了隐藏的错误消息：

OP的新增内容：

该问题与意外的只写属性有关。有

setBlockList

和

getBlocklist

（getter中的小“l”），这是一个打字错误。Drools抱怨说，因为它检测到两个属性，其中一个是只写属性

另一个不匹配是

isFixed

和

setFixed

。它适用于内置的

boolean

，但不适用于

boolean

对象

我很快就解决了这个问题

<?xml version="1.0" encoding="UTF-8"?>
<solver>
  <environmentMode>DEBUG</environmentMode>

  <solutionClass>domain.Sudoku</solutionClass>
  <planningEntityClass>domain.Digit</planningEntityClass>
  <scoreDrl>score.drl</scoreDrl>
  <scoreDefinition>
    <scoreDefinitionType>SIMPLE</scoreDefinitionType>
  </scoreDefinition>

  <termination>
    <scoreAttained>0</scoreAttained>
  </termination>
  <!--
  <constructionHeuristic>
    <constructionHeuristicType>FIRST_FIT_DECREASING</constructionHeuristicType>
    <constructionHeuristicPickEarlyType>FIRST_LAST_STEP_SCORE_EQUAL_OR_IMPROVING</constructionHeuristicPickEarlyType>
</constructionHeuristic> -->
  <constructionHeuristic>
    <constructionHeuristicType>FIRST_FIT</constructionHeuristicType>

      <moveFactoryClass>solution.RowChangeMoveFactory</moveFactoryClass>
    </selector>
    <acceptor>
      <completeSolutionTabuSize>1000</completeSolutionTabuSize>
    </acceptor>
    <forager>
      <!-- Real world problems require to use of <minimalAcceptedSelection> -->
    </forager>
  </localSearch>
</solver>