开源规则引擎 Drools 学习笔记 之 -- 1 cannot be cast to org.drools.compiler.kie.builder.impl.InternalKieModule
- Drools
- 时间：2021-07-15 15:00
- 6381人已阅读
简介
直接进入正题我们在使用开源规则引擎 Drools 的时候,启动的时候可能会抛出如下异常:java.lang.IllegalStateException: Failed to load ApplicationContextat org.springframework.test.context.cache.DefaultCacheA
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直接进入正题
我们在使用开源规则引擎 Drools 的时候, 启动的时候可能会抛出如下异常:
java.lang.IllegalStateException: Failed to load ApplicationContext at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:132) at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:124) at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:118) at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83) at org.springframework.boot.test.autoconfigure.SpringBootDependencyInjectionTestExecutionListener.prepareTestInstance(SpringBootDependencyInjectionTestExecutionListener.java:43) at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:244) at org.springframework.test.context.junit.jupiter.SpringExtension.postProcessTestInstance(SpringExtension.java:138) at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$invokeTestInstancePostProcessors$6(ClassBasedTestDescriptor.java:350) at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.executeAndMaskThrowable(ClassBasedTestDescriptor.java:355) at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$invokeTestInstancePostProcessors$7(ClassBasedTestDescriptor.java:350) at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193) at java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:175) at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1374) at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481) at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471) at java.util.stream.StreamSpliterators$WrappingSpliterator.forEachRemaining(StreamSpliterators.java:312) at java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:743) at java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:742) at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:580) at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.invokeTestInstancePostProcessors(ClassBasedTestDescriptor.java:349) at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$instantiateAndPostProcessTestInstance$4(ClassBasedTestDescriptor.java:270) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.instantiateAndPostProcessTestInstance(ClassBasedTestDescriptor.java:269) at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$testInstancesProvider$2(ClassBasedTestDescriptor.java:259) at java.util.Optional.orElseGet(Optional.java:267) at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$testInstancesProvider$3(ClassBasedTestDescriptor.java:258) at org.junit.jupiter.engine.execution.TestInstancesProvider.getTestInstances(TestInstancesProvider.java:31) at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$prepare$0(TestMethodTestDescriptor.java:101) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.prepare(TestMethodTestDescriptor.java:100) at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.prepare(TestMethodTestDescriptor.java:65) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$prepare$1(NodeTestTask.java:111) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.platform.engine.support.hierarchical.NodeTestTask.prepare(NodeTestTask.java:111) at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:79) at java.util.ArrayList.forEach(ArrayList.java:1249) at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:143) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129) at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126) at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84) at java.util.ArrayList.forEach(ArrayList.java:1249) at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:143) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129) at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137) at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127) at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126) at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84) at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32) at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57) at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51) at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:108) at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:88) at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:54) at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:67) at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:52) at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:96) at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:75) at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:71) at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33) at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:220) at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:53) Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'kieContainer' defined in class path resource [com/example/drools/droolsdemo/config/DroolsAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.kie.api.runtime.KieContainer]: Factory method 'kieContainer' threw exception; nested exception is java.lang.ClassCastException: com.example.drools.droolsdemo.config.DroolsAutoConfiguration$$Lambda$701/1083803390 cannot be cast to org.drools.compiler.kie.builder.impl.InternalKieModule at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:658) at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:486) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1334) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1177) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:564) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:524) at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:944) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:918) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:583) at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:758) at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:438) at org.springframework.boot.SpringApplication.run(SpringApplication.java:337) at org.springframework.boot.test.context.SpringBootContextLoader.loadContext(SpringBootContextLoader.java:123) at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:99) at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:124) ... 68 more Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.kie.api.runtime.KieContainer]: Factory method 'kieContainer' threw exception; nested exception is java.lang.ClassCastException: com.example.drools.droolsdemo.config.DroolsAutoConfiguration$$Lambda$701/1083803390 cannot be cast to org.drools.compiler.kie.builder.impl.InternalKieModule at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:653) ... 86 more Caused by: java.lang.ClassCastException: com.example.drools.droolsdemo.config.DroolsAutoConfiguration$$Lambda$701/1083803390 cannot be cast to org.drools.compiler.kie.builder.impl.InternalKieModule at org.drools.compiler.kie.builder.impl.KieServicesImpl.newKieContainer(KieServicesImpl.java:188) at org.drools.compiler.kie.builder.impl.KieServicesImpl.newKieContainer(KieServicesImpl.java:176) at com.example.drools.droolsdemo.config.DroolsAutoConfiguration.kieContainer(DroolsAutoConfiguration.java:48) at com.example.drools.droolsdemo.config.DroolsAutoConfiguration$$EnhancerBySpringCGLIB$$1626d42.CGLIB$kieContainer$3(<generated>) at com.example.drools.droolsdemo.config.DroolsAutoConfiguration$$EnhancerBySpringCGLIB$$1626d42$$FastClassBySpringCGLIB$$af4cd174.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:244) at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:331) at com.example.drools.droolsdemo.config.DroolsAutoConfiguration$$EnhancerBySpringCGLIB$$1626d42.kieContainer(<generated>) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ... 87 more
发现是DroolsAutoConfiguration类里面异常了。
package com.example.drools.droolsdemo.config;
import org.kie.api.KieBase;
import org.kie.api.KieServices;
import org.kie.api.builder.KieBuilder;
import org.kie.api.builder.KieFileSystem;
import org.kie.api.builder.KieRepository;
import org.kie.api.runtime.KieContainer;
import org.kie.api.runtime.KieSession;
import org.kie.internal.io.ResourceFactory;
import org.kie.spring.KModuleBeanFactoryPostProcessor;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;
import java.io.IOException;
@Configuration
public class DroolsAutoConfiguration {
private static final String RULES_PATH = "rules/";
@Bean
@ConditionalOnMissingBean(KieFileSystem.class)
public KieFileSystem kieFileSystem() throws IOException {
KieFileSystem kieFileSystem = getKieServices().newKieFileSystem();
for (Resource file : getRuleFiles()) {
kieFileSystem.write(ResourceFactory.newClassPathResource(RULES_PATH + file.getFilename(), "UTF-8"));
}
return kieFileSystem;
}
private Resource[] getRuleFiles() throws IOException {
ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();
return resourcePatternResolver.getResources("classpath*:" + RULES_PATH + "**/*.*");
}
@Bean
@ConditionalOnMissingBean(KieContainer.class)
public KieContainer kieContainer() throws IOException {
final KieRepository kieRepository = getKieServices().getRepository();
kieRepository.addKieModule(kieRepository::getDefaultReleaseId);
KieBuilder kieBuilder = getKieServices().newKieBuilder(kieFileSystem());
kieBuilder.buildAll();
return getKieServices().newKieContainer(kieRepository.getDefaultReleaseId());
}
private KieServices getKieServices() {
return KieServices.Factory.get();
}
@Bean
@ConditionalOnMissingBean(KieBase.class)
public KieBase kieBase() throws IOException {
return kieContainer().getKieBase();
}
@Bean
@ConditionalOnMissingBean(KieSession.class)
public KieSession kieSession() throws IOException {
KieSession kieSession = kieContainer().newKieSession();
return kieSession;
}
@Bean
@ConditionalOnMissingBean(KModuleBeanFactoryPostProcessor.class)
public KModuleBeanFactoryPostProcessor kiePostProcessor() {
return new KModuleBeanFactoryPostProcessor();
}
}此为初始化 drl 文件时的异常, 说明我们的 drl 文件不规范, Drools 不能解析成功.
我仔细检查了一下:
rule "read-Reading-speed"
when
$rlt:ReadingLevelTest(totalWordsNum != null,totalSecondTime != null)
$rl:ReadingLevel(readingSpeed == null)
then
$rl.setReadingSpeed($rlt.getTotalWordsNum()/$rlt.getTotalSecondTime()/60);
update($rl)
System.out.println("测评结果读速: " + $rl.toString());
end发现其实是因为在 then 中的 update($rl) 后没有用分号结尾, 加上分号运行正常.
when后面每行表达式后面是不需要添加分号结尾的then后面为java代码, 每行必须使用分号结尾, 如果我们忘记了添加分号,编译器也会报错题型的, 但是有一些特例, 比如Drools提供的方法update(),insert等等, 如果后面不加分号, 编译器是不会报错的, 但是运行的时候就会抛出解析失败!
原因二：
import的类被我删除了。
解决：
删除到错误引用就可以了。