Drools规则模板错误[错误：未关闭@if{}块。使用占位符时应为@end{}]

如果在子类集合列表中使用占位符，则无法编译drools规则模板

我有一个简单的类结构

public class Parent {
   private List<Child> children;
}
public class Child {
   private String gender;
}

模板中硬编码为“男性”时无问题

Parent($children: children)
Child(gender == "MALE") from $children

有什么想法吗？谢谢你的帮助

完整错误堆栈跟踪：

[Line: 42, Column: 0]
    at org.drools.core.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:39)
    at org.drools.core.common.DefaultAgenda.handleException(DefaultAgenda.java:1291)
    at org.drools.core.phreak.RuleExecutor.innerFireActivation(RuleExecutor.java:442)
    at org.drools.core.phreak.RuleExecutor.fireActivation(RuleExecutor.java:380)
    at org.drools.core.phreak.RuleExecutor.fire(RuleExecutor.java:136)
    at org.drools.core.phreak.RuleExecutor.evaluateNetworkAndFire(RuleExecutor.java:89)
    at org.drools.core.concurrent.AbstractRuleEvaluator.internalEvaluateAndFire(AbstractRuleEvaluator.java:33)
    at org.drools.core.concurrent.SequentialRuleEvaluator.evaluateAndFire(SequentialRuleEvaluator.java:43)
    at org.drools.core.common.DefaultAgenda.fireLoop(DefaultAgenda.java:1101)
    at org.drools.core.common.DefaultAgenda.internalFireAllRules(DefaultAgenda.java:1048)
    at org.drools.core.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1040)
    at org.drools.core.impl.StatefulKnowledgeSessionImpl.internalFireAllRules(StatefulKnowledgeSessionImpl.java:1341)
    at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1332)
    at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1316)
    at org.drools.template.parser.TemplateDataListener.finishSheet(TemplateDataListener.java:158)
    at org.drools.decisiontable.parser.xls.ExcelParser.finishSheet(ExcelParser.java:277)
    at org.drools.decisiontable.parser.xls.ExcelParser.processSheet(ExcelParser.java:212)
    at org.drools.decisiontable.parser.xls.ExcelParser.parseWorkbook(ExcelParser.java:105)
    at org.drools.decisiontable.parser.xls.ExcelParser.parseFile(ExcelParser.java:84)
    at org.drools.decisiontable.ExternalSpreadsheetCompiler.compile(ExternalSpreadsheetCompiler.java:140)
    at org.drools.decisiontable.ExternalSpreadsheetCompiler.compile(ExternalSpreadsheetCompiler.java:168)
    at org.drools.decisiontable.ExternalSpreadsheetCompiler.compile(ExternalSpreadsheetCompiler.java:99)
    at org.drools.decisiontable.ExternalSpreadsheetCompiler.compile(ExternalSpreadsheetCompiler.java:85)
    at com.dhl.gssdemo.config.SpringDroolsConfig.addTemplateContent(SpringDroolsConfig.java:112)
    at com.dhl.gssdemo.config.SpringDroolsConfig.classpathDrlKieBase(SpringDroolsConfig.java:102)
    at com.dhl.gssdemo.config.SpringDroolsConfig$$EnhancerBySpringCGLIB$$583d8208.CGLIB$classpathDrlKieBase$0(<generated>)
    at com.dhl.gssdemo.config.SpringDroolsConfig$$EnhancerBySpringCGLIB$$583d8208$$FastClassBySpringCGLIB$$25a5fef6.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.dhl.gssdemo.config.SpringDroolsConfig$$EnhancerBySpringCGLIB$$583d8208.classpathDrlKieBase(<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)
    ... 52 common frames omitted
Caused by: java.lang.RuntimeException: [Error: unclosed @if{} block. expected @end{}]

[行：42，列：0]
位于org.drools.core.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException（DefaultConsequenceExceptionHandler.java:39）
位于org.drools.core.common.DefaultAgenda.handleException（DefaultAgenda.java:1291）
位于org.drools.core.phreak.RuleExecutor.innerFireActivation（RuleExecutor.java:442）
位于org.drools.core.phreak.RuleExecutor.fireActivation（RuleExecutor.java:380）
位于org.drools.core.phreak.RuleExecutor.fire（RuleExecutor.java:136）
位于org.drools.core.phreak.RuleExecutor.evaluateneworkandfire（RuleExecutor.java:89）
位于org.drools.core.concurrent.AbstractRuleEvaluator.internalEvaluateAndFire（AbstractRuleEvaluator.java:33）
位于org.drools.core.concurrent.SequentialRuleEvaluator.evaluateAndFire（SequentialRuleEvaluator.java:43）
位于org.drools.core.common.DefaultAgenda.fireLoop（DefaultAgenda.java:1101）
位于org.drools.core.common.DefaultAgenda.internalFireAllRules（DefaultAgenda.java:1048）
位于org.drools.core.common.DefaultAgenda.fireAllRules（DefaultAgenda.java:1040）
位于org.drools.core.impl.StatefulKnowledgeSessionImpl.internalFireAllRules（StatefulKnowledgeSessionImpl.java:1341）
位于org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules（StatefulKnowledgeSessionImpl.java:1332）
位于org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules（StatefulKnowledgeSessionImpl.java:1316）
位于org.drools.template.parser.TemplateDataListener.finishSheet（TemplateDataListener.java:158）
位于org.drools.decisiontable.parser.xls.ExcelParser.finishSheet（ExcelParser.java:277）
位于org.drools.decisiontable.parser.xls.ExcelParser.processSheet（ExcelParser.java:212）
位于org.drools.decisiontable.parser.xls.ExcelParser.parseWorkbook（ExcelParser.java:105）
位于org.drools.decisiontable.parser.xls.ExcelParser.parseFile（ExcelParser.java:84）
位于org.drools.decisiontable.ExternalSpreadsheetCompiler.compile（ExternalSpreadsheetCompiler.java:140）
位于org.drools.decisiontable.ExternalSpreadsheetCompiler.compile（ExternalSpreadsheetCompiler.java:168）
位于org.drools.decisiontable.ExternalSpreadsheetCompiler.compile（ExternalSpreadsheetCompiler.java:99）
位于org.drools.decisiontable.ExternalSpreadsheetCompiler.compile（ExternalSpreadsheetCompiler.java:85）
位于com.dhl.gssdemo.config.SpringDroolsConfig.addTemplateContent（SpringDroolsConfig.java:112）
位于com.dhl.gssdemo.config.SpringDroolsConfig.classpathDrlKieBase（SpringDroolsConfig.java:102）
位于com.dhl.gssdemo.config.SpringDroolsConfig$$EnhancerBySpringCGLIB$$583d8208.CGLIB$classpathdrllkiebase$0（）
在com.dhl.gssdemo.config.SpringDroolsConfig$$EnhancerBySpringCGLIB$$583d8208$$FastClassBySpringCGLIB$$25a5fef6.invoke（）上
位于org.springframework.cglib.proxy.MethodProxy.invokeSuper（MethodProxy.java:244）
位于org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept（ConfigurationClassEnhancer.java:331）
在com.dhl.gssdemo.config.SpringDroolsConfig$$EnhancerBySpringCGLIB$$583d8208.classpathDrlKieBase（）上
在sun.reflect.NativeMethodAccessorImpl.invoke0（本机方法）处
位于sun.reflect.NativeMethodAccessorImpl.invoke（NativeMethodAccessorImpl.java:62）
在sun.reflect.DelegatingMethodAccessorImpl.invoke（DelegatingMethodAccessorImpl.java:43）中
位于java.lang.reflect.Method.invoke（Method.java:498）
位于org.springframework.beans.factory.support.SimpleInstallationStrategy.instantiate（SimpleInstallationStrategy.java:154）
... 省略52个公共帧
原因：java.lang.RuntimeException:[错误：未关闭@if{}块。应为@end{}]

我也遇到了同样的问题，我认为这与解决MVEL表达式有关，但我通过使用以下解决方法解决了它（使用$$而不是$）

就你而言

父母（子女：子女）

---

Child（gender==“@{gender}”）来自$$children

drools的哪个版本？你好，Roddy，它是7.40.0。Finalor不使用$作为绑定变量是解决它的另一种方法

[Line: 42, Column: 0]
    at org.drools.core.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:39)
    at org.drools.core.common.DefaultAgenda.handleException(DefaultAgenda.java:1291)
    at org.drools.core.phreak.RuleExecutor.innerFireActivation(RuleExecutor.java:442)
    at org.drools.core.phreak.RuleExecutor.fireActivation(RuleExecutor.java:380)
    at org.drools.core.phreak.RuleExecutor.fire(RuleExecutor.java:136)
    at org.drools.core.phreak.RuleExecutor.evaluateNetworkAndFire(RuleExecutor.java:89)
    at org.drools.core.concurrent.AbstractRuleEvaluator.internalEvaluateAndFire(AbstractRuleEvaluator.java:33)
    at org.drools.core.concurrent.SequentialRuleEvaluator.evaluateAndFire(SequentialRuleEvaluator.java:43)
    at org.drools.core.common.DefaultAgenda.fireLoop(DefaultAgenda.java:1101)
    at org.drools.core.common.DefaultAgenda.internalFireAllRules(DefaultAgenda.java:1048)
    at org.drools.core.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1040)
    at org.drools.core.impl.StatefulKnowledgeSessionImpl.internalFireAllRules(StatefulKnowledgeSessionImpl.java:1341)
    at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1332)
    at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1316)
    at org.drools.template.parser.TemplateDataListener.finishSheet(TemplateDataListener.java:158)
    at org.drools.decisiontable.parser.xls.ExcelParser.finishSheet(ExcelParser.java:277)
    at org.drools.decisiontable.parser.xls.ExcelParser.processSheet(ExcelParser.java:212)
    at org.drools.decisiontable.parser.xls.ExcelParser.parseWorkbook(ExcelParser.java:105)
    at org.drools.decisiontable.parser.xls.ExcelParser.parseFile(ExcelParser.java:84)
    at org.drools.decisiontable.ExternalSpreadsheetCompiler.compile(ExternalSpreadsheetCompiler.java:140)
    at org.drools.decisiontable.ExternalSpreadsheetCompiler.compile(ExternalSpreadsheetCompiler.java:168)
    at org.drools.decisiontable.ExternalSpreadsheetCompiler.compile(ExternalSpreadsheetCompiler.java:99)
    at org.drools.decisiontable.ExternalSpreadsheetCompiler.compile(ExternalSpreadsheetCompiler.java:85)
    at com.dhl.gssdemo.config.SpringDroolsConfig.addTemplateContent(SpringDroolsConfig.java:112)
    at com.dhl.gssdemo.config.SpringDroolsConfig.classpathDrlKieBase(SpringDroolsConfig.java:102)
    at com.dhl.gssdemo.config.SpringDroolsConfig$$EnhancerBySpringCGLIB$$583d8208.CGLIB$classpathDrlKieBase$0(<generated>)
    at com.dhl.gssdemo.config.SpringDroolsConfig$$EnhancerBySpringCGLIB$$583d8208$$FastClassBySpringCGLIB$$25a5fef6.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.dhl.gssdemo.config.SpringDroolsConfig$$EnhancerBySpringCGLIB$$583d8208.classpathDrlKieBase(<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)
    ... 52 common frames omitted
Caused by: java.lang.RuntimeException: [Error: unclosed @if{} block. expected @end{}]