public FileExtFilter(String mask)
		{
			StringTokenizer st = new StringTokenizer(mask, "|");
			while (st.hasMoreElements())
			{
				String token = st.nextToken().trim();
				if (st.hasMoreElements()) {
					if (token.length() == 0) {
						// no extension
					} else {
						if (token.startsWith("null")) {
							if (token.length() > 4) {
								token = token.substring(5).trim();
							} else {
								token = "";
							}
						}
						if (token.length() > 0) {
							extensions.add(token.toLowerCase());
						}
					}
				} else {
					String type = token.substring(0, 1);
					int val = Integer.parseInt(type);
					if (val == 0) {
						mode = JFileChooser.FILES_ONLY;
					} else if (val == 1) {
						mode = JFileChooser.DIRECTORIES_ONLY;
					} else {
						mode = JFileChooser.FILES_AND_DIRECTORIES;
					}
					description = token.substring(1);
				}
			}
			fileChooser.setFileSelectionMode(mode);
		}