Here you can find the source of isEmail(String email)
public static boolean isEmail(String email)
//package com.java2s; import java.util.regex.Pattern; public class Main { private final static Pattern emailer = Pattern .compile("\\w+([-+.]\\w+)*@\\w+([-.]\\w+)*\\.\\w+([-.]\\w+)*"); public static boolean isEmail(String email) { if (email == null || email.trim().length() == 0) return false; return emailer.matcher(email).matches(); }/*from w ww . j a v a 2s . co m*/ }