Write code to get Host name from a string using regex
//package com.book2s; import java.util.regex.Matcher; import java.util.regex.Pattern; public class Main { public static void main(String[] argv) { String url = "www.book2s.com"; System.out.println(getHost(url)); }//ww w. j a va 2 s . c o m public static String getHost(String url) { if (url == null || "".equals(url.trim())) return null; Pattern p = Pattern.compile("(?<=//|)((\\w)+\\.)+\\w+"); Matcher matcher = p.matcher(url); if (matcher.find()) return matcher.group(); else return null; } }