001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 */ 019 020 package org.apache.myfaces.tobago.util; 021 022 import javax.faces.context.FacesContext; 023 import java.util.HashSet; 024 import java.util.Map; 025 import java.util.Locale; 026 027 public class AccessKeyMap { 028 029 private static final char[] KEYS = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 030 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 031 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'}; 032 033 private static final String REQUEST_MAP_KEY = "accessKeysRequestMapKey"; 034 035 private HashSet set; 036 private StringBuilder duplicated = new StringBuilder(); 037 038 039 public static AccessKeyMap getInstance(FacesContext facesContext) { 040 final Map requestMap = facesContext.getExternalContext().getRequestMap(); 041 AccessKeyMap keyMap = (AccessKeyMap) requestMap.get(REQUEST_MAP_KEY); 042 if (keyMap == null) { 043 keyMap = new AccessKeyMap(); 044 requestMap.put(REQUEST_MAP_KEY, keyMap); 045 } 046 return keyMap; 047 } 048 049 private AccessKeyMap() { 050 set = new HashSet(); 051 } 052 053 private HashSet getSet() { 054 return set; 055 } 056 057 private String getDuplicated() { 058 return duplicated.toString(); 059 } 060 061 private void addDublicated(char key) { 062 duplicated = duplicated.append(key); 063 } 064 065 public static boolean addAccessKey(FacesContext facesContext, Character key) { 066 key = key.toString().toLowerCase(Locale.ENGLISH).charAt(0); 067 final AccessKeyMap instance = getInstance(facesContext); 068 if (instance.getSet().contains(key)) { 069 instance.addDublicated(key); 070 return false; 071 } else { 072 instance.getSet().add(key); 073 return true; 074 } 075 } 076 077 public static String getDublicatedKeys(FacesContext facesContext) { 078 return getInstance(facesContext).getDuplicated(); 079 } 080 081 public static String getUnusedKeys(FacesContext facesContext) { 082 HashSet set = getInstance(facesContext).getSet(); 083 StringBuilder sb = new StringBuilder(); 084 for (char key : KEYS) { 085 if (!set.contains(Character.valueOf(key))) { 086 sb.append(key); 087 } 088 } 089 return sb.toString(); 090 } 091 }