Java tutorial
//package com.java2s; import android.text.TextUtils; import android.widget.EditText; import java.util.regex.Pattern; public class Main { private static final String EMAIL_NUMBER_REG = "^[0-9a-zA-Z][a-z0-9A-Z\\._-]{1,}@[a-z0-9-]{1,}[a-z0-9]\\.[a-z\\.]{1,}[a-z]$"; public static boolean isValidEmail(EditText paramEditText) { if (paramEditText == null) { throw new NullPointerException("EditText can't null"); } return isValidEmail(paramEditText.getText().toString()); } public static boolean isValidEmail(String paramString) { if (TextUtils.isEmpty(paramString)) { return false; } return Pattern.compile(EMAIL_NUMBER_REG).matcher(paramString).matches(); } }