public class LinkService implements IServiceHandler {
	/** objectId parameter name */
	private static final String OBJECT_ID = "objectId";
	/** objectType parameter name */
	private static final String OBJECT_TYPE = "objectType";

	@Override
	public void service() throws IOException, ServletException {
		try {
			HttpServletRequest request = ContextProvider.getRequest();

			String objectType = request.getParameter(OBJECT_TYPE);
			String objectId = request.getParameter(OBJECT_ID);

			if (objectType != null && objectId != null) {
				EClassifier classifier = ModelUtil.getModelClassifier(objectType);
				IBasicObjectRefService<BasicObject, ObjectRef> service = CommonPlugin.getDefault().getRefService(
						classifier);
				final BasicObject object = service.findById(objectId);

				UIUtil.openViewerEditor(object);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}

		IWorkbench workbench = PlatformUI.getWorkbench();
		IWorkbenchWindow window = workbench.getActiveWorkbenchWindow();
		if (window == null && workbench.getWorkbenchWindowCount() > 0) {
			window = workbench.getWorkbenchWindows()[0];
		}
		if (window == null) {
			throw new RuntimeException("no workbench window found, can not open editor");
		}
		IWorkbenchPage page = window.getActivePage();