Drools 6.1.0.Final CEP 示例 : Unable to create Field Extractor

标签 drools complex-event-processing drools-flow kie

我在尝试将 CEP 示例从 Drools 5X 转换为 6X 时遇到奇怪的错误: - 准确地说是 Drool 6.1.0.Final。

我这个小项目的灵感来源可以在以下链接找到:=> PlugTree .

我收到的错误表明 Drools 无法创建字段提取器 - 当他们忘记在其域 POJO 中创建 setter/getter 时会出现错误。

SEVERE: Unable to build KieBaseModel:rules Unable to create Field Extractor for 'amount'Field/method 'amount' not found for class 'com.sample.Sale' : [Rule name='StoreOne - Has Passed it's Sales Record'] java.lang.RuntimeException: Field/method 'amount' not found for class 'com.sample.Sale'

我已将问题追溯到规则文件中的“声明”语句(我将在下面列出完整的列表):

declare Sale
    @role(event)
end

仅使用此命令会导致错误(顺便说一句，这在 V5 中不会发生)，但是使用下一个“更改的”声明语句不会导致错误。它什么也没做...

declare Sale
    @role(event)
    article : String
    amount : long
    quantity : int
end

它所做的——什么也没有。它可以编译、运行，但事实只是没有被插入(或识别)。

这是我的 Java 测试工具:

package com.sample.cep;

import org.kie.api.KieBaseConfiguration;
import org.kie.api.KieServices;
import org.kie.api.conf.EventProcessingOption;
import org.kie.api.event.rule.DebugAgendaEventListener;
import org.kie.api.event.rule.DebugRuleRuntimeEventListener;
import org.kie.api.runtime.KieContainer;
import org.kie.api.runtime.KieSession;
import org.kie.api.runtime.conf.ClockTypeOption;
import org.kie.api.runtime.rule.EntryPoint;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


public class CEPExample {

    public static void main(String[] args) {


        try {
            // load up the knowledge base & get the kSession
            KieServices ks = KieServices.Factory.get();
            KieContainer kContainer = ks.getKieClasspathContainer();
            KieSession kSession = kContainer.newKieSession("ksession-rules");

            // CEP - get the KIE related configuration container and set the EventProcessing (from default cloud) to Stream
            KieBaseConfiguration config = ks.newKieBaseConfiguration();
            config.setOption( EventProcessingOption.STREAM );


            // Listeners
            kSession.addEventListener( new DebugAgendaEventListener() );
            kSession.addEventListener( new DebugRuleRuntimeEventListener() );

            // To setup a file based audit logger, uncomment the next line 
            // KieRuntimeLogger loggerKie = ks.getLoggers().newFileLogger( kSession, "./logger" );
            // KieRuntimeLogger consoleLogger = ks.getLoggers().newConsoleLogger(kSession); 

            Logger logger = LoggerFactory.getLogger(CEPExample.class);
            logger.info("\n*********************************>>>> Drools CEP Example \n");   

            // Each Event is Inserted into WorkingMemory through an *EntryPoint*
            EntryPoint entryPointStoreOne = kSession.getEntryPoint( "StoreOne" );
            EntryPoint entryPointStoreTwo = kSession.getEntryPoint( "StoreTwo" );


            // Insert EventData into WM for StoreOne
            entryPointStoreOne.insert(new Sale("meat", 40, 5) );
            entryPointStoreOne.insert(new Sale("bananna", 5, 10) );
            entryPointStoreOne.insert(new Sale("pear", 5, 10) );
            entryPointStoreOne.insert(new Sale("yogurt", 5, 50) );
            entryPointStoreOne.insert(new Sale("led TV", 10000, 1) );

            // Insert EventData into WM for StoreTwo
            entryPointStoreTwo.insert(new Sale("meat", 40, 5) );
            entryPointStoreTwo.insert(new Sale("bananna", 5, 10) );
            entryPointStoreTwo.insert(new Sale("pear", 5, 10) );
            entryPointStoreTwo.insert(new Sale("yogurt", 5, 50) );



            // Fire all Rules
            kSession.fireAllRules();


            // Close Logger
            //logger.close();

            // Close the session
            kSession.destroy();

            System.out.println("*** DONE *** ");

        } catch (Throwable t) {
            t.printStackTrace();
        } 

    } // End Method - MAIN




//  // Helper Class to INSERTEVENT
//  private static void insertEvent(EntryPoint entryPoint, Sale sale, String article, long amount, int quantity) {
//  
//      sale.setArticle(article);
//      sale.setAmount(amount);
//      sale.setQuantity(quantity);
//      entryPoint.insert(sale);
//      
//  } // End Class insertEvent  



}// End Class CEPExample

这是我的规则文件:

//created on: Nov 28, 2014
package com.sample

import com.sample.Sale;


// Declarations

declare Sale
    @role(event)

    //article : String
    //amount : long
    //quantity : int
end



rule "StoreOne - Has Passed it's Sales Record"
    when
        Number( $totalSalesAmount : intValue, intValue > 1000 )
        from accumulate ( Sale($amount : amount, $quantity : quantity) 
        from entry-point "StoreOne", sum( $amount*$quantity ))
    then
        System.out.println("StoreOne - Has passed its Sales Record!");
end


rule "StoreTwo - has Passed its Sales Record"
    when
        Number( $totalSalesAmount : intValue, intValue > 1000 )
        from accumulate ( Sale($amount : amount, $quantity : quantity) from entry-point "StoreTwo", sum( $amount * $quantity ))
    then
        System.out.println("StoreTwo - Has passed its Sales Record!");  
end

还有我的 kmodule.xml 文件:

<?xml version="1.0" encoding="UTF-8"?>
<kmodule xmlns="http://jboss.org/kie/6.0.0/kmodule">
    <kbase name="rules" packages="rules">
        <ksession name="ksession-rules"/>
    </kbase>
</kmodule>

我确实认为这也是相关的 - 使用监听器的咨询输出(对于更改声明语句(列出属性):

Nov 29, 2014 4:31:10 PM org.drools.compiler.kie.builder.impl.ClasspathKieProject notifyKieModuleFound
INFO: Found kmodule: file:/C:/Users/versaggi/workspace-spring-framework/CEPProject/target/classes/META-INF/kmodule.xml
Nov 29, 2014 4:31:10 PM org.drools.compiler.kie.builder.impl.KieRepositoryImpl addKieModule
INFO: KieModule was added:FileKieModule[ ReleaseId=com.versaggi:CEPProject:0.0.1-SNAPSHOTfile=C:\Users\versaggi\workspace-spring-framework\CEPProject\target\classes]
Nov 29, 2014 4:31:14 PM com.sample.cep.CEPExample main
INFO: 
*********************************>>>> Drools CEP Example 

==>[ObjectInsertedEventImpl: getFactHandle()=[fact 0:1:24780333:24780333:1:StoreOne:NON_TRAIT:com.sample.cep.Sale@17a1e2d], getObject()=com.sample.cep.Sale@17a1e2d, getKnowledgeRuntime()=org.drools.core.impl.StatefulKnowledgeSessionImpl@527389, getPropagationContext()=PhreakPropagationContext [entryPoint=EntryPoint::StoreOne, factHandle=[fact 0:1:24780333:24780333:1:StoreOne:NON_TRAIT:com.sample.cep.Sale@17a1e2d], leftTuple=null, originOffset=-1, propagationNumber=2, rule=null, type=0]]
==>[ObjectInsertedEventImpl: getFactHandle()=[fact 0:2:20723018:20723018:2:StoreOne:NON_TRAIT:com.sample.cep.Sale@13c354a], getObject()=com.sample.cep.Sale@13c354a, getKnowledgeRuntime()=org.drools.core.impl.StatefulKnowledgeSessionImpl@527389, getPropagationContext()=PhreakPropagationContext [entryPoint=EntryPoint::StoreOne, factHandle=[fact 0:2:20723018:20723018:2:StoreOne:NON_TRAIT:com.sample.cep.Sale@13c354a], leftTuple=null, originOffset=-1, propagationNumber=3, rule=null, type=0]]
==>[ObjectInsertedEventImpl: getFactHandle()=[fact 0:3:16489063:16489063:3:StoreOne:NON_TRAIT:com.sample.cep.Sale@fb9a67], getObject()=com.sample.cep.Sale@fb9a67, getKnowledgeRuntime()=org.drools.core.impl.StatefulKnowledgeSessionImpl@527389, getPropagationContext()=PhreakPropagationContext [entryPoint=EntryPoint::StoreOne, factHandle=[fact 0:3:16489063:16489063:3:StoreOne:NON_TRAIT:com.sample.cep.Sale@fb9a67], leftTuple=null, originOffset=-1, propagationNumber=4, rule=null, type=0]]
==>[ObjectInsertedEventImpl: getFactHandle()=[fact 0:4:33509294:33509294:4:StoreOne:NON_TRAIT:com.sample.cep.Sale@1ff4fae], getObject()=com.sample.cep.Sale@1ff4fae, getKnowledgeRuntime()=org.drools.core.impl.StatefulKnowledgeSessionImpl@527389, getPropagationContext()=PhreakPropagationContext [entryPoint=EntryPoint::StoreOne, factHandle=[fact 0:4:33509294:33509294:4:StoreOne:NON_TRAIT:com.sample.cep.Sale@1ff4fae], leftTuple=null, originOffset=-1, propagationNumber=5, rule=null, type=0]]
==>[ObjectInsertedEventImpl: getFactHandle()=[fact 0:5:27946348:27946348:5:StoreOne:NON_TRAIT:com.sample.cep.Sale@1aa6d6c], getObject()=com.sample.cep.Sale@1aa6d6c, getKnowledgeRuntime()=org.drools.core.impl.StatefulKnowledgeSessionImpl@527389, getPropagationContext()=PhreakPropagationContext [entryPoint=EntryPoint::StoreOne, factHandle=[fact 0:5:27946348:27946348:5:StoreOne:NON_TRAIT:com.sample.cep.Sale@1aa6d6c], leftTuple=null, originOffset=-1, propagationNumber=6, rule=null, type=0]]
==>[ObjectInsertedEventImpl: getFactHandle()=[fact 0:6:26643062:26643062:6:StoreTwo:NON_TRAIT:com.sample.cep.Sale@1968a76], getObject()=com.sample.cep.Sale@1968a76, getKnowledgeRuntime()=org.drools.core.impl.StatefulKnowledgeSessionImpl@527389, getPropagationContext()=PhreakPropagationContext [entryPoint=EntryPoint::StoreTwo, factHandle=[fact 0:6:26643062:26643062:6:StoreTwo:NON_TRAIT:com.sample.cep.Sale@1968a76], leftTuple=null, originOffset=-1, propagationNumber=7, rule=null, type=0]]
==>[ObjectInsertedEventImpl: getFactHandle()=[fact 0:7:26870209:26870209:7:StoreTwo:NON_TRAIT:com.sample.cep.Sale@19a01c1], getObject()=com.sample.cep.Sale@19a01c1, getKnowledgeRuntime()=org.drools.core.impl.StatefulKnowledgeSessionImpl@527389, getPropagationContext()=PhreakPropagationContext [entryPoint=EntryPoint::StoreTwo, factHandle=[fact 0:7:26870209:26870209:7:StoreTwo:NON_TRAIT:com.sample.cep.Sale@19a01c1], leftTuple=null, originOffset=-1, propagationNumber=8, rule=null, type=0]]
==>[ObjectInsertedEventImpl: getFactHandle()=[fact 0:8:1161635:1161635:8:StoreTwo:NON_TRAIT:com.sample.cep.Sale@11b9a3], getObject()=com.sample.cep.Sale@11b9a3, getKnowledgeRuntime()=org.drools.core.impl.StatefulKnowledgeSessionImpl@527389, getPropagationContext()=PhreakPropagationContext [entryPoint=EntryPoint::StoreTwo, factHandle=[fact 0:8:1161635:1161635:8:StoreTwo:NON_TRAIT:com.sample.cep.Sale@11b9a3], leftTuple=null, originOffset=-1, propagationNumber=9, rule=null, type=0]]
==>[ObjectInsertedEventImpl: getFactHandle()=[fact 0:9:2257152:2257152:9:StoreTwo:NON_TRAIT:com.sample.cep.Sale@227100], getObject()=com.sample.cep.Sale@227100, getKnowledgeRuntime()=org.drools.core.impl.StatefulKnowledgeSessionImpl@527389, getPropagationContext()=PhreakPropagationContext [entryPoint=EntryPoint::StoreTwo, factHandle=[fact 0:9:2257152:2257152:9:StoreTwo:NON_TRAIT:com.sample.cep.Sale@227100], leftTuple=null, originOffset=-1, propagationNumber=10, rule=null, type=0]]
*** DONE ***

由于网络上流传的 V5 中的 CEP 示例非常少，V6 KIE 中的示例更少，因此如果您对这个错误的起源以及如何纠正它有任何想法，我将不胜感激。

最佳答案

DRL 语言的 declare 语句可用于两个截然不同的目的:

  1. 向 POJO 添加元数据(例如 @role)
  2. 声明一个类(不需要任何 Java 代码)以在规则(和 Java 应用程序代码)中使用

这一区别源自于 declare 语句中是否存在一个或多个字段。

当使用第二种形式时，Java代码无法以通常的方式创建声明类的对象。您必须使用迂回技术，使用 (KieBase.getFactType()) 从包中定位类，创建实例 (FactType.newInstance()) 并使用通用 setter 添加属性值(FactType.set()、setFromMap())。

如果您同时有 POJO Sale 和声明的类 Sale，则很可能会出现问题。我还没有尝试过使用 kmodule.xml 进行构建(我从来没有这样做过)，但是从 Java 调用 KieBuilder 并检查错误会产生(销售字段未注释):

[main] ERROR org.drools.compiler.kie.builder.impl.AbstractKieModule - Unable to build KieBaseModel:defaultKieBase
New declaration of sale.Sale can't declaredeclares a different set of fields  
existing : ...
declared : ...

顺便说一句，此示例未使用任何事件处理功能，并且该问题与 cEP 完全无关。

稍后

插入“标准事实”和“事件事实”的唯一区别是引擎可能必须添加时间戳字段(除非您的元数据表明它已经作为属性存在)。

从技术上讲，对于插入的编码方式，它取决于事实类型的定义方式:要么通过Java类(根据声明添加“事件”风格)第 1 项)或通过完整的声明，如前所述。没有进一步的区别 w.r.t。在普通事实和事件事实之间插入。

此外，访问(检索属性以进行模式评估)没有任何区别，除了事件具有附加时间戳属性(除非映射到显式属性)，该时间戳属性在使用时间运算符时会隐式检索已应用。

处理方面存在差异，最明显的是适用于事件本身(而不是属性)的时间运算符。此外，事件可能有资格自动撤回，并且可以在窗口中选择它们。

关于Drools 6.1.0.Final CEP 示例 : Unable to create Field Extractor，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/27207454/

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