Here you can find the source of isValidEmail(CharSequence target)
public static boolean isValidEmail(CharSequence target)
//package com.java2s; public class Main { public static boolean isValidEmail(CharSequence target) { try {//from w w w . ja v a2 s . co m return android.util.Patterns.EMAIL_ADDRESS.matcher(target) .matches(); } catch (NullPointerException exception) { return false; } } }