2021-07-29 17:37:48,777 WARN  [org.acm.sch.mes.TimeTableMessagingHandler] (ForkJoinPool.commonPool-worker-19) Error during processing a solver request (1).: org.kie.memorycompiler.KieMemoryCompilerException: [org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (2:110) : cannot find symbol
  symbol:   class CompiledNetwork
  location: package org.drools.ancompiler, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (4:20) : package org.drools.core.spi does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (5:45) : package org.drools.modelcompiler.constraints does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (6:29) : package org.drools.core.rule does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (7:31) : package org.drools.core.reteoo does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (8:31) : package org.drools.core.reteoo does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (9:31) : package org.drools.core.reteoo does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (10:31) : package org.drools.core.reteoo does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (11:31) : package org.drools.core.reteoo does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (12:31) : package org.drools.core.reteoo does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (13:31) : package org.drools.core.reteoo does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (14:94) : package org.drools.core.spi does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (14:178) : package org.drools.core.util.index does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (17:62) : package org.drools.core.common does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (23:55) : package org.drools.core.common does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (52:63) : package org.drools.core.common does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (52:110) : package org.drools.core.spi does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (52:161) : package org.drools.core.common does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (66:63) : package org.drools.core.common does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (66:113) : package org.drools.core.reteoo does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (66:176) : package org.drools.core.spi does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (66:227) : package org.drools.core.common does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (93:64) : package org.kie.api.definition.rule does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (97:65) : package org.kie.api.definition.rule does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (101:63) : package org.drools.core.common does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (102:63) : package org.drools.core.reteoo does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (103:60) : package org.drools.core.spi does not exist, org/drools/ancompiler/Compiledorg_acme_schooltimetabling_domain_LessonNetwork31008790748.java (104:63) : package org.drools.core.common does not exist]
	at org.kie.memorycompiler.KieMemoryCompiler.compileNoLoad(KieMemoryCompiler.java:133)
	at org.kie.memorycompiler.KieMemoryCompiler.compileNoLoad(KieMemoryCompiler.java:101)
	at org.kie.memorycompiler.KieMemoryCompiler.compile(KieMemoryCompiler.java:53)
	at org.kie.memorycompiler.KieMemoryCompiler.compile(KieMemoryCompiler.java:39)
	at org.drools.ancompiler.KieBaseUpdaterANC.inMemoryUpdate(KieBaseUpdaterANC.java:66)
	at org.drools.ancompiler.KieBaseUpdaterANC.run(KieBaseUpdaterANC.java:52)
	at org.drools.ancompiler.KieBaseUpdaterANC.generateAndSetInMemoryANC(KieBaseUpdaterANC.java:99)
	at org.optaplanner.core.impl.score.stream.drools.DroolsConstraintSessionFactory.buildKieBaseFromModel(DroolsConstraintSessionFactory.java:85)
	at org.optaplanner.core.impl.score.stream.drools.DroolsConstraintSessionFactory.buildSession(DroolsConstraintSessionFactory.java:126)
	at org.optaplanner.core.impl.score.director.stream.DroolsConstraintStreamScoreDirectorFactory.newConstraintStreamingSession(DroolsConstraintStreamScoreDirectorFactory.java:50)
	at org.optaplanner.core.impl.score.director.stream.DroolsConstraintStreamScoreDirector.resetConstraintStreamingSession(DroolsConstraintStreamScoreDirector.java:75)
	at org.optaplanner.core.impl.score.director.stream.DroolsConstraintStreamScoreDirector.setWorkingSolution(DroolsConstraintStreamScoreDirector.java:67)
	at org.optaplanner.core.impl.solver.scope.SolverScope.setWorkingSolutionFromBestSolution(SolverScope.java:215)
	at org.optaplanner.core.impl.solver.AbstractSolver.solvingStarted(AbstractSolver.java:80)
	at org.optaplanner.core.impl.solver.DefaultSolver.solvingStarted(DefaultSolver.java:200)
	at org.optaplanner.core.impl.solver.DefaultSolver.solve(DefaultSolver.java:174)
	at org.acme.schooltimetabling.messaging.TimeTableMessagingHandler.lambda$solve$0(TimeTableMessagingHandler.java:79)
	at java.base/java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1736)
	at java.base/java.util.concurrent.CompletableFuture$AsyncRun.exec(CompletableFuture.java:1728)
	at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290)
	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1020)
	at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1656)
	at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1594)
	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:183)