//This custom code iterates recursively over all folders in the local database, does a browse query to list
//their contents and adds up the total size of each. At the end a dialog is displayed with all folder sizes.
//WARNING: This breaks the workflow model slightly because there is no input or output, it just cancels the whole workflow.

public static List<AnnotatedPluginDocument> performOperation(List<AnnotatedPluginDocument> documents, Options options,
													  ProgressListener progressListener) throws DocumentOperationException {
	final Map<Long, String> map = new TreeMap<Long, String>();
	getFolderSizes(map, PluginUtilities.getGeneiousService(PluginUtilities.LOCAL_DATABASE_SERVICE_UNIQUE_ID), progressListener);

	StringBuilder sb = new StringBuilder();
	for (Map.Entry<Long, String> entry : map.entrySet()) {
		sb.append(StringUtilities.bytesToString(entry.getKey())).append(": ").append(entry.getValue()).append("\n");
	}

	Dialogs.DialogOptions dialogOptions = new Dialogs.DialogOptions(Dialogs.OK_ONLY, "Results");
	dialogOptions.setModal(false);
	Dialogs.showDialog(dialogOptions, sb.toString());
	throw new DocumentOperationException.Canceled();
}

public static void getFolderSizes(Map<Long, String> map, GeneiousService service, ProgressListener progressListener) throws DocumentOperationException {
	List<GeneiousService> childServices = service.getChildServices();
	for (GeneiousService childService : childServices) {
		if (progressListener.isCanceled()) {
			throw new DocumentOperationException.Canceled();
		}
		DatabaseService databaseService = (DatabaseService)childService;
		List<AnnotatedPluginDocument> docs;
		try {
			docs = (databaseService).retrieve(Query.Factory.createBrowseQuery(), ProgressListener.EMPTY);
		} catch (DatabaseServiceException e) {
			throw new DocumentOperationException(e);
		}
		Long totalSize = 0L;
		for (AnnotatedPluginDocument doc : docs) {
			Object size = doc.getFieldValue("document_size");
			if (size != null) {
				totalSize += ((Number)size).longValue();
			}
		}
		if (totalSize > 0) {
			while (map.containsKey(totalSize)) {
				totalSize ++; //HACK since I cant use an anonymous inner class to sort the map by values :(
			}
			map.put(totalSize, databaseService.getFullPath());
		}
		//sb.append(StringUtilities.bytesToString(totalSize)).append(": ").append(databaseService.getFullPath()).append("\n");
		getFolderSizes(map, childService, progressListener);
	}
}

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