Question

我们正在使用 Drools 6.3和JDK 1.8 版本在我们的计划中实施某些业务规则。我们使用drools中的trait / don概念编写了我们的业务规则之一，如下所示：

declare Patient
@Traitable
end

declare trait PatientTrait end

declare EvalTime
@role( event)
@timestamp (evalTime)
evalTime: Date
end

declare Fired
  guid: String
end

declare trait eligible_adult_patient extends com.test.trait.PatientTrait end


rule "External Data eligible_adult_patient"
when
    EvalTime($evalTime: evalTime)
    $item: Patient(birthDate before [23741d] $evalTime)

then
    don($item, eligible_adult_patient.class, true);

end

rule "Rule logic for rule585bf9ed_a1ae_46de_8f5c_65ce605d48b9"
when
    not(Fired( guid == "585bf9ed-a1ae-46de-8f5c-65ce605d48b9" ))
    patient:Patient()
    (exists(eligible_adult_patient())))
then
    insert(new Fired("585bf9ed-a1ae-46de-8f5c-65ce605d48b9"));
end

我们使用以下代码生成KIEBase：

KieContainer kieContainer = kieServices.newKieContainer(kieBuilder.getKieModule().getReleaseId());
KieBase kieBase = kieContainer.getKieBase();

生成KIEBase后，我们尝试序列化KIEBase，然后将其作为Blob存储到数据库中。 对于规则的下一个请求，我们尝试从DB检索KIEBase并对其进行反序列化。在此期间，我们得到以下异常：

java.io.InvalidClassException: org.drools.core.reteoo.TraitObjectTypeNode; no valid constructor
    at java.io.ObjectStreamClass$ExceptionInfo.newInvalidClassException(ObjectStreamClass.java:150)
    at java.io.ObjectStreamClass.checkDeserialize(ObjectStreamClass.java:790)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1775)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
    at org.drools.core.reteoo.BetaNode.readExternal(BetaNode.java:219)
    at org.drools.core.reteoo.NotNode.readExternal(NotNode.java:63)
    at java.io.ObjectInputStream.readExternalData(ObjectInputStream.java:1842)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1799)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
    at org.drools.core.reteoo.AbstractTerminalNode.readExternal(AbstractTerminalNode.java:62)
    at org.drools.core.reteoo.RuleTerminalNode.readExternal(RuleTerminalNode.java:159)
    at java.io.ObjectInputStream.readExternalData(ObjectInputStream.java:1842)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1799)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
    at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1707)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1345)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
    at java.util.HashMap.readObject(HashMap.java:1396)
    at sun.reflect.GeneratedMethodAccessor3.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1058)
    at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1900)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1801)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
    at org.drools.core.reteoo.ReteooBuilder.readExternal(ReteooBuilder.java:405)
    at java.io.ObjectInputStream.readExternalData(ObjectInputStream.java:1842)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1799)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
    at org.drools.core.impl.KnowledgeBaseImpl.readExternal(KnowledgeBaseImpl.java:500)
    at java.io.ObjectInputStream.readExternalData(ObjectInputStream.java:1842)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1799)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
    at org.drools.core.util.DroolsStreamUtils.streamIn(DroolsStreamUtils.java:205)
    at org.drools.core.util.DroolsStreamUtils.streamIn(DroolsStreamUtils.java:161)
    at org.drools.core.util.DroolsStreamUtils.streamIn(DroolsStreamUtils.java:131)
    at org.drools.core.util.DroolsStreamUtils.streamIn(DroolsStreamUtils.java:116)

当我们查看 org.drools.core.reteoo.TraitObjectTypeNode 类时，它没有no-arg构造函数，这会在反序列化时导致上述问题。

所以我的问题是：

针对上述反序列化问题的任何建议解决方案
推荐的方法是将KIEBase仅存储在内存缓存中，还是将KIEBase存储在存储（如DB）/分布式缓存（序列化和反序列化）中也很好

赞赏这方面的任何帮助

Punith

Drools - 使用特征时的KIEBase反序列化异常

0 个答案: