java正则婚配Url

java正则匹配Url
public static void getUrl(String file) throws IOException{final String regex = "([a-zA-Z]+://[www]?.[A-Z,a-z,0-9,\\p{Punct},\\+]+) " ;Pattern p =Pattern.compile( regex,Pattern.MULTILINE | Pattern.DOTALL); BufferedReader br;br = new BufferedReader(new FileReader(file));String line = null;while((line=br.readLine())!=null){Matcher m = p.matcher(line);while(m.find()){System.out.println(m.group());}}br.close();}