public Map<Properties, Graph<Node, Edge>> loadGraphs(String dirGraphPath) {
		Map<Properties, Graph<Node, Edge>> map = new HashMap<>();
		File directory = new File(dirGraphPath);
		for (File graphFile : directory.listFiles()) {
			if (graphFile.isFile() && (graphFile.getName().endsWith(".graphml") || graphFile.getName().endsWith(".paj"))) {
				try {
					Properties properties = new Properties();
					properties.setProperty("graphType", graphFile.getName());
					map.put(properties, GraphUtils.read(graphFile.getAbsolutePath()));
				} catch (IOException e) {
					e.printStackTrace();
				} catch (ParserConfigurationException e) {
					e.printStackTrace();
				} catch (SAXException e) {
					e.printStackTrace();
				}
			}
		}
		return map;
	}