}
public void refresh() {
try {
final PluginManager mgr = InitialNaming.lookup(PluginManager.NAME);
PluginDescriptorModel pdm =
(PluginDescriptorModel) mgr.getRegistry().getPluginDescriptor(pluginId);
if (pdm != null) {
isvalid = false;
for (PluginDescriptorModel fdm : pdm.fragments()) {
if (fdm.getId().equals(fragmentId)) {
buffer = fdm.getJarFile().getBuffer();
isvalid = buffer != null;
}
}