Package wt.clients.util

Class TaskDelegateFactory

java.lang.Object
wt.clients.util.TaskDelegateFactory
public class TaskDelegateFactory extends Object
Class TaskDelegateFactory is a utility class which contains factory methods for instantiating TaskDelegate objects. This class instantiates task delegate objects based upon either a given class or the class of a given object.

The TaskDelegateFactory assumes a specific naming convention when trying to instantiate a TaskDelegate for a given class or object. If the fully-qualified class of the business object for which to instantiate a delegate is mysite.mypackage.MyBusinessObject, this factory will attempt to find a task delegate class whose fully-qualified class name is mysite.clients.mypackage.MyBusinessObjectTaskDelegate. For example, when attempting to instantiate a task delegate for wt.doc.WTDocument objects, the factory will look for a class whose fully-qualified name is wt.clients.doc.WTDocument. Given the fully-qualified class name of apkg.bpkg.cpkg.dpkg.Eobject, this factory will follow the following search algorithm to try and find a corresponding task delegate class:

  1. apkg.clients.bpkg.cpkg.dpkg.EobjectTaskDelegate
  2. apkg.bpkg.clients.cpkg.dpkg.EobjectTaskDelegate
  3. apkg.bpkg.cpkg.clients.dpkg.EobjectTaskDelegate
  4. apkg.bpkg.cpkg.dpkg.clients.EobjectTaskDelegate
If no delegate is found using this algorithm, the same algorithm will be applied to the parent of the given class. If no delegate is found applying this algorithm to the parent class, the same algorithm will be applied to the interfaces implemented by the given class. The TaskDelegateFactory class together with the TaskDelegate class form in a system in which business objects can be created, updated, viewed and deleted without knowing the specific type of the business object. For example: 
    public class MyDisplay extends Frame {
       ...
       public void handleViewEvent( Event evt ) {
          Object obj_to_view = evt.getSource();
          TaskDelegate delegate =
                       TaskDelegateFactory.instantiateTaskDelegate( obj_to_view );
                      if( delegate != null ) {
                         delegate.setParentApplet( getParentApplet() );
                         delegate.setParentFrame( this );
                         delegate.setObject( obj_to_view );

                 try {
                      delegate.launchViewTask();
                   } catch (TaskDelegateException tde) {
             // Handle Exception
                   }
       }
       ...
    }


Supported API: true

Extendable: false