java - Drools规则语法中的异常

我正在尝试使用如下两个不同的POJO类编写流口水的规则。

  for (int i = 0; i < 5; i++) {

        dbRules = new DbRules(i, "Rule Name - " + i, "  $mdmContractHeader : MdmContractHeader();  $contractHeader1 : ContractHeader (supplierName==$mdmContractHeader.supplierName); "
                + " &&  contractHeader:ContractHeader(supplierId >= 100)",
                "System.out.print(\"Test, Drools rule - " + i
                        + ".! \"); System.out.println(contractHeader.getSupplierName());");
        list.add(dbRules);
    }

执行后，我面临以下异常。看来我在pojo类声明中遇到了错误。

  Exception in thread "main" java.lang.RuntimeException: Unable to get KieModule, Errors Existed: Error Messages:
      Message [id=1, kieBase=defaultKieBase, level=ERROR, path=rules/Sample.drl, line=1, column=0
    text=[ERR 102] Line 1:306 mismatched input '$contractHeader1' in rule "Rule Name - 0"]
        Message [id=2, kieBase=defaultKieBase, level=ERROR, path=rules/Sample.drl, line=1, column=0
      text=[ERR 102] Line 1:723 mismatched input '$contractHeader1' in rule "Rule Name - 1"]
      Message [id=3, kieBase=defaultKieBase, level=ERROR, path=rules/Sample.drl, line=1, column=0
     text=[ERR 102] Line 1:1140 mismatched input '$contractHeader1' in rule "Rule Name - 2"]
     Message [id=4, kieBase=defaultKieBase, level=ERROR, path=rules/Sample.drl, line=1, column=0
    text=[ERR 102] Line 1:1557 mismatched input '$contractHeader1' in rule "Rule Name - 3"]
    Message [id=5, kieBase=defaultKieBase, level=ERROR, path=rules/Sample.drl, line=1, column=0
    text=[ERR 102] Line 1:1974 mismatched input '$contractHeader1' in rule "Rule Name - 4"]
     Message [id=6, kieBase=defaultKieBase, level=ERROR, path=rules/Sample.drl, line=0, column=0
      text=Parser returned a null Package]
  ---
  Warning Messages:
 ---
 Info Messages:

at org.drools.compiler.kie.builder.impl.KieBuilderImpl.getKieModule(KieBuilderImpl.java:467)
at org.drools.compiler.kie.builder.impl.KieBuilderImpl.getKieModule(KieBuilderImpl.java:453)
at com.sample.StringDroolsMdm.executeRules(StringDroolsMdm.java:118)
at com.sample.StringDroolsMdm.main(StringDroolsMdm.java:70)

我已经更新了StringBuffer中的内容，如下所示，但仍然出现相同的异常。

 import com.model.ContractHeader;
 import com.model.MdmContractHeader;
 import static com.service.SupplierService.isRuleAppliesToSupplier;
 rule "Rule Name - 0"
  when
 cHeader:ContractHeader()
 eval(isRuleAppliesToSupplier((cHeader.getSupplierName()) , 0 )) &&
 (
 $mdmContractHeader:MdmContractHeader($s : supplierName)
 $myContractHeader:ContractHeader(supplierName == $s)
  contractHeader:ContractHeader(supplierId >= 100)
 )
  then
 System.out.print("Test, Drools rule - 0.! "); System.out.println(contractHeader.getSupplierName());
 end;

例外是：

Exception in thread "main" java.lang.RuntimeException: Unable to get KieModule, Errors Existed: Error Messages:
Message [id=1, kieBase=defaultKieBase, level=ERROR, path=rules/Sample.drl, line=10, column=0
   text=[ERR 102] Line 10:1 mismatched input '$myContractHeader' in rule "Rule Name - 0"]
Message [id=2, kieBase=defaultKieBase, level=ERROR, path=rules/Sample.drl, line=0, column=0
   text=Parser returned a null Package]
---

最佳答案

您可以做一些事情来使规则看起来更好：


在第一个模式之后和;关键字之后删除end。
在规则名称之后以及\n和when关键字之后添加then。
在每个模式之后添加一个\n。
不要在模式之间使用不必要的&&。


这些更改之后，您的规则应如下所示：

rule "Rule Name - 0"
when
  cHeader:ContractHeader()
  eval(isRuleAppliesToSupplier((cHeader.getSupplierName()) , 0 )) &&
  (
    $mdmContractHeader : MdmContractHeader( $s : supplierName )
    $contractHeader1 : ContractHeader ( supplierName == $s )
    contractHeader: ContractHeader(supplierId >= 100)
  )
then
  System.out.print("Test, Drools rule - 0.! "); System.out.println(contractHeader.getSupplierName());
end;

我的猜测是由于\n模式后缺少MdmContractHeader()而导致该错误。

希望能帮助到你，