001 /* AccessibleStateSet.java -- the combined state of an accessible object 002 Copyright (C) 2002, 2005 Free Software Foundation 003 004 This file is part of GNU Classpath. 005 006 GNU Classpath is free software; you can redistribute it and/or modify 007 it under the terms of the GNU General Public License as published by 008 the Free Software Foundation; either version 2, or (at your option) 009 any later version. 010 011 GNU Classpath is distributed in the hope that it will be useful, but 012 WITHOUT ANY WARRANTY; without even the implied warranty of 013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014 General Public License for more details. 015 016 You should have received a copy of the GNU General Public License 017 along with GNU Classpath; see the file COPYING. If not, write to the 018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 019 02110-1301 USA. 020 021 Linking this library statically or dynamically with other modules is 022 making a combined work based on this library. Thus, the terms and 023 conditions of the GNU General Public License cover the whole 024 combination. 025 026 As a special exception, the copyright holders of this library give you 027 permission to link this library with independent modules to produce an 028 executable, regardless of the license terms of these independent 029 modules, and to copy and distribute the resulting executable under 030 terms of your choice, provided that you also meet, for each linked 031 independent module, the terms and conditions of the license of that 032 module. An independent module is a module which is not derived from 033 or based on this library. If you modify this library, you may extend 034 this exception to your version of the library, but you are not 035 obligated to do so. If you do not wish to do so, delete this 036 exception statement from your version. */ 037 038 package javax.accessibility; 039 040 import java.util.Locale; 041 import java.util.Vector; 042 043 /** 044 * Describes all elements of an accessible object's state. For example, an 045 * object may be enabled and have focus. 046 * 047 * @author Eric Blake (ebb9@email.byu.edu) 048 * @see AccessibleState 049 * @since 1.2 050 * @status updated to 1.4 051 */ 052 public class AccessibleStateSet 053 { 054 /** 055 * The list of states, should be instances of AccessibleState. Don't set 056 * this to null. 057 * 058 * @see #add(AccessibleState) 059 * @see #addAll(AccessibleState[]) 060 * @see #remove(AccessibleState) 061 * @see #contains(AccessibleState) 062 * @see #toArray() 063 * @see #clear() 064 */ 065 protected Vector<AccessibleState> states = new Vector<AccessibleState>(); 066 067 /** 068 * Create an empty state set. 069 */ 070 public AccessibleStateSet() 071 { 072 } 073 074 /** 075 * Create a state set initialized with the given states, duplicates are 076 * ignored. 077 * 078 * @param states the states to insert 079 * @throws NullPointerException if states is null 080 */ 081 public AccessibleStateSet(AccessibleState[] states) 082 { 083 addAll(states); 084 } 085 086 /** 087 * Add a new state to the current set. Return true if the state was added, 088 * as duplicates are ignored. Entering a null state will cause problems 089 * later, so don't do it. 090 * 091 * @param state the state to add 092 * @return true if the state was added 093 */ 094 public boolean add(AccessibleState state) 095 { 096 return states.contains(state) ? false : states.add(state); 097 } 098 099 /** 100 * Add all of the states to the current set. Duplicates are ignored. 101 * Entering a null state will cause problems later, so don't do it. 102 * 103 * @param array the array of states to add 104 * @throws NullPointerException if array is null 105 */ 106 public void addAll(AccessibleState[] array) 107 { 108 int i = array.length; 109 while (--i >= 0) 110 add(array[i]); 111 } 112 113 /** 114 * Remove a state from the set. If a state was removed, return true. 115 * 116 * @param state the state to remove 117 * @return true if the set changed 118 */ 119 public boolean remove(AccessibleState state) 120 { 121 return states.remove(state); 122 } 123 124 /** 125 * Clear all states in the set. 126 */ 127 public void clear() 128 { 129 states.clear(); 130 } 131 132 /** 133 * Check if the current state is in the set. 134 * 135 * @param state the state to locate 136 * @return true if it is in the set 137 */ 138 public boolean contains(AccessibleState state) 139 { 140 return states.contains(state); 141 } 142 143 /** 144 * Return the state set as an array. 145 * 146 * @return an array of the current states 147 */ 148 public AccessibleState[] toArray() 149 { 150 AccessibleState[] result = new AccessibleState[states.size()]; 151 states.toArray(result); 152 return result; 153 } 154 155 /** 156 * Return a localized, comma-separated string representing all states 157 * in the set. This is in arbitrary order. 158 * 159 * @return the string representation 160 * @see AccessibleBundle#toDisplayString(String, Locale) 161 */ 162 public String toString() 163 { 164 int i = states.size(); 165 if (i == 0) 166 return ""; 167 // Pre-allocate an average of 10 chars per state. 168 StringBuffer b = new StringBuffer(i * 10); 169 while (--i >= 0) 170 b.append(states.get(i)).append(','); 171 return b.substring(0, b.length() - 1); 172 } 173 } // class AccessibleStateSet