正则表达式：获取一个URL中的Host

Connection conn = C3P0Util.getInstance().getConnection(C3P0Util.SOURCE);
		String url = conn.getMetaData().getURL();
		String host = "";
		Pattern p = Pattern.compile("(?<=//|)((w)+.)+w+");
		Matcher matcher = p.matcher(url);
		if (matcher.find()) {
			host = matcher.group();
		}
		System.out.println(host);