So far, you’ve created a *FinderImpl class, defined a findBy* finder method
in that class, and implemented the finder method using Dynamic Query. Now how do
you call your finder method from the service layer?
When you ran Service Builder, the *Finder interface was generated (e.g.,
GuestbookFinder). For proper separation of concerns, only a local or remote service
implementation (i.e., *LocalServiceImpl or *ServiceImpl) in your service
module should invoke the *Finder class. The portlet classes in your
application’s web module invoke the business logic of the services published
from your application’s service module. The services, in turn, access the data
model using the persistence layer’s finder classes.
You’ll add a method in the *LocalServiceImpl class that invokes the finder
method implementation via the *Finder class. Then you’ll rebuild your
application’s service layer so that the portlet classes and JSPs in your web
module can access the services.
For example, for the Guestbook application, you’d add the following method to
the EntryLocalServiceImpl class:
public List<Entry> findByEntryNameGuestbookName(String entryName,
String guestbookName) throws SystemException {
return entryFinder.findByEntryNameGuestbookName(String entryName,
String guestbookName);
}
After you’ve added your findBy* method to your *LocalServiceImpl class, run
Service Builder to generate the interface and make the finder method available
in the EntryLocalService class.
Now you can indirectly call the finder method from your portlet class or from a
JSP by calling _entryLocalService.findByEntryNameGuestbookName(...)!
Congratulations on following the three step process of developing a dynamic query in a custom finder and exposing it as a service for your portlet!