Java tutorial
//package com.java2s; //License from project: Apache License import android.content.Context; import android.text.TextUtils; import android.util.Log; import android.widget.EditText; import android.widget.Toast; public class Main { private static final boolean YES = true; private static final boolean NO = false; private static final String EMAIL_PATTERN_1 = "[a-zA-Z0-9._-]+@[a-z]+\\.+[a-z]+"; private static final String EMAIL_PATTERN_2 = "[a-zA-Z0-9._-]+@[a-z]+\\.+[a-z]+\\.+[a-z]+"; public static boolean validateEmail(EditText editText) { if (nonEmpty(editText)) { String emailAsString = removeBlankSpace(editText.getText().toString()); return emailAsString.matches(EMAIL_PATTERN_1) || emailAsString.matches(EMAIL_PATTERN_2); } else { Log.d("SERI_PAR->Error", "edit text object is null"); return NO; } } public static boolean validateEmail(Context context, EditText editText, String msg) { if (validateEmail(editText)) { return YES; } else { showToast(context, msg); return NO; } } public static boolean nonEmpty(EditText editText) { if (editText != null && !(TextUtils.isEmpty(editText.getText().toString().trim()))) { return YES; } else { Log.d("SERI_PAR->Error", "edit text object is null"); return NO; } } public static boolean nonEmpty(Context context, EditText editText, String msg) { if (nonEmpty(editText)) { return YES; } else { showToast(context, msg); return NO; } } public static String removeBlankSpace(String value) { value = value.replace(" ", ""); return value; } public static void showToast(Context context, String msg) { Toast.makeText(context, msg, Toast.LENGTH_SHORT).show(); } }