Here you can find the source of containsOnlyAlphaDigitHyphen( final Collection
public static boolean containsOnlyAlphaDigitHyphen( final Collection<String> values)
//package com.java2s; /*//from w ww .jav a2 s. c o m * Copyright (C) 2009 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import android.text.TextUtils; import java.util.Arrays; import java.util.Collection; public class Main { /** * <p> * This is useful since vCard 3.0 often requires the ("X-") properties and groups should contain only alphabets, digits, and * hyphen. * </p> * <p> * Note: It is already known some devices (wrongly) outputs properties with characters which should not be in the field. One * example is "X-GOOGLE TALK". We accept such kind of input but must never output it unless the target is very specific to the * device which is able to parse the malformed input. * </p> */ public static boolean containsOnlyAlphaDigitHyphen( final String... values) { if (values == null) { return true; } return containsOnlyAlphaDigitHyphen(Arrays.asList(values)); } public static boolean containsOnlyAlphaDigitHyphen( final Collection<String> values) { if (values == null) { return true; } final int upperAlphabetFirst = 0x41; // A final int upperAlphabetAfterLast = 0x5b; // [ final int lowerAlphabetFirst = 0x61; // a final int lowerAlphabetAfterLast = 0x7b; // { final int digitFirst = 0x30; // 0 final int digitAfterLast = 0x3A; // : final int hyphen = '-'; for (final String str : values) { if (TextUtils.isEmpty(str)) { continue; } final int length = str.length(); for (int i = 0; i < length; i = str.offsetByCodePoints(i, 1)) { int codepoint = str.codePointAt(i); if (!((lowerAlphabetFirst <= codepoint && codepoint < lowerAlphabetAfterLast) || (upperAlphabetFirst <= codepoint && codepoint < upperAlphabetAfterLast) || (digitFirst <= codepoint && codepoint < digitAfterLast) || (codepoint == hyphen))) { return false; } } } return true; } }