*/
public <T extends ResourceComponent<?>> ResourceUpgradeCallback<T> getResourceUpgradeCallback(String pluginName,
String callbackClassName) throws PluginContainerException {
// same classloader as plugin discovery component would use - with null parent, its just the plugin classloader
ResourceUpgradeCallback callback = instantiateInDiscoveryComponentClassLoader(pluginName, callbackClassName,
ResourceUpgradeCallback.class);
if (log.isDebugEnabled()) {
log.debug("Created resource upgrade callback [" + callbackClassName + "] for plugin [" + pluginName + ']');
}