java - 如何使用 Drools debugWorkingMemorylistener？

Question

以下代码行直接来自文档

ksession.addEventListener(new DebugWorkingMemoryEventListener());

eclipse中提示如下错误

The method addEventListener(WorkingMemoryEventListener) in the type WorkingMemoryEventManager is not applicable for the arguments (DebugWorkingMemoryEventListener)

Answer 1

您可能会导入 org.drools.event.DebugWorkingMemoryEventListener 而不是 org.drools.event.rule.DebugWorkingMemoryEventListener。

在我们的例子中，以下代码可以正常工作:

import org.drools.event.rule.DebugWorkingMemoryEventListener;
import org.drools.event.rule.ObjectInsertedEvent;
import org.drools.event.rule.ObjectRetractedEvent;
import org.drools.event.rule.ObjectUpdatedEvent;
...
StatelessKnowledgeSession ksession = kbase.newStatelessKnowledgeSession();
ksession.addEventListener(new DebugWorkingMemoryEventListener() {
    @Override
    public void objectInserted(ObjectInsertedEvent event) {
        System.out.println(event);
    }

    @Override
    public void objectRetracted(ObjectRetractedEvent event) {
        System.out.println(event);
    }

    @Override
    public void objectUpdated(ObjectUpdatedEvent event) {
        System.out.println(event);
    }
});