Question

我有以下代码：

KieSession kSession = JPAKnowledgeService.loadStatefulKnowledgeSession(someId, kieBase, null, env)

for (FactHandle f : kSession.getFactHandles()) {
    Object sessionObject = kSession.getObject(f);
    logger.info(String.format("Fact:  %s", sessionObject.toString()));
}

kSession.insert(someFact);

// Let's loop again to see if our fact is indeed there
for (FactHandle f : kSession.getFactHandles()) {
    Object sessionObject = kSession.getObject(f);
    logger.info(String.format("Fact:  %s", sessionObject.toString()));
}

// Do something else with someFact, insert it into some db

// factHandle is null
FactHandle factHandle = kSession.getFactHandle(someFact);

基本上，我正在加载我的持久性KieSession，向它添加一个事实，循环查看事实以检查新添加的事实确实存在，但是当我尝试将其恢复时，factHandle object为null。我试图使用Drools与基于身份的断言模式。所以我的相关问题是：

为什么我的事实处理空？ someFact在内存中的位置可能已在Do something else with someFact, insert it into some db阶段发生变化，是否会对问题产生影响？
Drools如何比较身份？我在private long id对象上提交了someFact，注明了@Id。
我正在创建我的KieContainer和KieBase，如下所示：

```

@Bean
public KieServices kieServices() {
    return KieServices.Factory.get();
}

@Bean
public KieContainer kieContainer() throws IOException {

    final KieRepository kieRepository = kieServices().getRepository();

    kieRepository.addKieModule(new KieModule() {
        @Override
        public ReleaseId getReleaseId() {
            return kieRepository.getDefaultReleaseId();
        }
    });

    KieFileSystem kfs = kieServices().newKieFileSystem();
    PathMatchingResourcePatternResolver pmrs = new PathMatchingResourcePatternResolver();
    Resource[] files = pmrs.getResources("classpath*:com/company/**/rules/*.drl");

    for(Resource file : files) {
        String myString = IOUtils.toString(file.getInputStream(), "UTF-8");
        kfs.write("src/main/resources/"+ file.getFilename(), myString);
    }

    KieBuilder kieBuilder = kieServices().newKieBuilder(kfs);
    kieBuilder.buildAll();
    return kieServices().newKieContainer(kieRepository.getDefaultReleaseId());
}

@Bean
public KieBase kieBase() throws IOException {
    KieBaseConfiguration kieBaseConfiguration = kieServices().newKieBaseConfiguration();
    kieBaseConfiguration.setProperty("assertBehaviour", "equality");
    return KnowledgeBaseFactory.newKnowledgeBase(kieBaseConfiguration);
}

```

如果我必须切换到基于相等的断言，我在我的对象上实现了equals和hashCode方法，但找不到定义KieBase断言的方法为EQUALITY。我怎么能这样做？

Answer 1

只有someFact中Do something else with someFact, insert it into some db在@Id中更改内存的位置才有效，因此Drools无法使用身份模式进行比较。
内存中的位置。不是Javax KieBaseConfiguration kieBaseConfiguration = kieServices().newKieBaseConfiguration(); kieBaseConfiguration.setOption(EqualityBehaviorOption.EQUALITY); return kieContainer().newKieBase(kieBaseConfiguration);注释。

以下是将引擎置于等式模式的方法：

insert into yourTable ( ...)      
with names as (
    select 'A' as name from dual union all
    select 'B' as name from dual union all
    select 'C' as name from dual 
),
dates as (
          select date' 2017-01-01' + level -1 as yourDate
          from dual
          connect by date' 2016-01-01' + level -1 <= date '2017-02-20'
         )
select rownum, name, yourDate
from names
       cross join dates

getFactHandle方法为Drools

1 个答案: