Java tutorial
//package com.java2s; import android.text.TextUtils; import java.util.regex.Matcher; import java.util.regex.Pattern; public class Main { public static boolean isEmail(String email) { if (TextUtils.isEmpty(email)) return false; String expression = "^[\\w\\.-]+@([\\w\\-]+\\.)+[A-Z]{2,4}$"; Pattern pattern = Pattern.compile(expression, Pattern.CASE_INSENSITIVE); Matcher matcher = pattern.matcher(email); if (matcher.matches()) return true; else return false; } }