private Dispatcher() {
IConfigurationElement[] config =
RegistryFactory.getRegistry().getConfigurationElementsFor(DISPATCH_FILTER_ID);
for (IConfigurationElement element : config) {
try {
boolean isFilter = "filter".equals(element.getName()); // $NON-NLS-1$
if (isFilter) {
DispatchFilter filter = new DispatchFilter(element);
filters.putSingle(filter.getPriority(), filter);
}
} catch (Exception e) {
logger.error("Error processing dispatch filter", e); // $NON-NLS-1$
}
}
}
/**
* Dispatch the given object to a dispatch handler if a matching filter can be found for the
* object's class. The dispatch handler is instantiated using the {@link ContextInjectionFactory},
* which injects the handler using the provided context.
*
* @param object Object to dispatch
* @param intent Intent that loaded the dispatched object, <code>null</code> if object is not the
* result of an intent
* @param context Context to use for injection into the handler
* @return True if a dispatch handler was found to handle the object
*/
public boolean dispatch(Object object, Intent intent, IEclipseContext context) {
if (object == null) {
return false;
}
DispatchFilter filter = findFilter(object);
Class<? extends IDispatchHandler> handlerClass = filter == null ? null : filter.getHandler();
if (handlerClass == null) {
logger.error("Could not find dispatch handler for object: " + object); // $NON-NLS-1$
return false;
}
IEclipseContext activeLeaf = context.getActiveLeaf();
IEclipseContext child = activeLeaf.createChild();
IDispatchHandler handler = ContextInjectionFactoryThreadSafe.make(handlerClass, child);
handler.handle(object, intent);
return true;
}
/**
* Find the best dispatch filter for the given object's class.
*
* @param object Object to find a filter for
* @return Dispatch filter for the object's class, or null if no matching filter could be found
*/
public DispatchFilter findFilter(Object object) {
if (object == null) {
return null;
}
int minDistance = Integer.MAX_VALUE;
DispatchFilter closest = null;
for (List<DispatchFilter> list : filters.values()) {
for (DispatchFilter filter : list) {
int distance = distanceToClosestType(object.getClass(), filter.getTypes());
if (distance >= 0 && distance < minDistance) {
minDistance = distance;
closest = filter;
}
}
}
return closest;
}
