java - PreUpdate Hooks in play framework，如何获取请求的旧值？

Question

我正在尝试使用 EBEAN preUpdate 挂钩。我以这种方式设置了一个测试类

public class MessageController extends BeanPersistAdapter {

@Override
public boolean isRegisterFor(Class<?> cls) {
    if (cls.equals(Message.class)){
        return true;
    }
    return false;
}

@Override
public void postLoad(Object bean, Set<String> includedProperties) {
}

@Override
public boolean preUpdate(BeanPersistRequest<?> request) {
    Logger.info("Update Record!");
    // Message bean = request.getBean();
    Message newModel = (Message) request.getBean();
    Message oldModel = (Message) request.getOldValues();
    //      
    System.out.println("... OrderController > inserting: "+ newModel.title);
    System.out.println("... OrderController > replacing: "+ oldModel.title);
    return true;

}

问题是， newModel.title 和 oldModel.title 返回相同的值。我想念什么？