J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1998-2003 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package javax.swing.text; |
| 27 | |
| 28 | import java.io.Serializable; |
| 29 | |
| 30 | /** |
| 31 | * A TabSet is comprised of many TabStops. It offers methods for locating the |
| 32 | * closest TabStop to a given position and finding all the potential TabStops. |
| 33 | * It is also immutable. |
| 34 | * <p> |
| 35 | * <strong>Warning:</strong> |
| 36 | * Serialized objects of this class will not be compatible with |
| 37 | * future Swing releases. The current serialization support is |
| 38 | * appropriate for short term storage or RMI between applications running |
| 39 | * the same version of Swing. As of 1.4, support for long term storage |
| 40 | * of all JavaBeans<sup><font size="-2">TM</font></sup> |
| 41 | * has been added to the <code>java.beans</code> package. |
| 42 | * Please see {@link java.beans.XMLEncoder}. |
| 43 | * |
| 44 | * @author Scott Violet |
| 45 | */ |
| 46 | public class TabSet implements Serializable |
| 47 | { |
| 48 | /** TabStops this TabSet contains. */ |
| 49 | private TabStop[] tabs; |
| 50 | /** |
| 51 | * Since this class is immutable the hash code could be |
| 52 | * calculated once. MAX_VALUE means that it was not initialized |
| 53 | * yet. Hash code shouldn't has MAX_VALUE value. |
| 54 | */ |
| 55 | private int hashCode = Integer.MAX_VALUE; |
| 56 | |
| 57 | /** |
| 58 | * Creates and returns an instance of TabSet. The array of Tabs |
| 59 | * passed in must be sorted in ascending order. |
| 60 | */ |
| 61 | public TabSet(TabStop[] tabs) { |
| 62 | // PENDING(sky): If this becomes a problem, make it sort. |
| 63 | if(tabs != null) { |
| 64 | int tabCount = tabs.length; |
| 65 | |
| 66 | this.tabs = new TabStop[tabCount]; |
| 67 | System.arraycopy(tabs, 0, this.tabs, 0, tabCount); |
| 68 | } |
| 69 | else |
| 70 | this.tabs = null; |
| 71 | } |
| 72 | |
| 73 | /** |
| 74 | * Returns the number of Tab instances the receiver contains. |
| 75 | */ |
| 76 | public int getTabCount() { |
| 77 | return (tabs == null) ? 0 : tabs.length; |
| 78 | } |
| 79 | |
| 80 | /** |
| 81 | * Returns the TabStop at index <code>index</code>. This will throw an |
| 82 | * IllegalArgumentException if <code>index</code> is outside the range |
| 83 | * of tabs. |
| 84 | */ |
| 85 | public TabStop getTab(int index) { |
| 86 | int numTabs = getTabCount(); |
| 87 | |
| 88 | if(index < 0 || index >= numTabs) |
| 89 | throw new IllegalArgumentException(index + |
| 90 | " is outside the range of tabs"); |
| 91 | return tabs[index]; |
| 92 | } |
| 93 | |
| 94 | /** |
| 95 | * Returns the Tab instance after <code>location</code>. This will |
| 96 | * return null if there are no tabs after <code>location</code>. |
| 97 | */ |
| 98 | public TabStop getTabAfter(float location) { |
| 99 | int index = getTabIndexAfter(location); |
| 100 | |
| 101 | return (index == -1) ? null : tabs[index]; |
| 102 | } |
| 103 | |
| 104 | /** |
| 105 | * @return the index of the TabStop <code>tab</code>, or -1 if |
| 106 | * <code>tab</code> is not contained in the receiver. |
| 107 | */ |
| 108 | public int getTabIndex(TabStop tab) { |
| 109 | for(int counter = getTabCount() - 1; counter >= 0; counter--) |
| 110 | // should this use .equals? |
| 111 | if(getTab(counter) == tab) |
| 112 | return counter; |
| 113 | return -1; |
| 114 | } |
| 115 | |
| 116 | /** |
| 117 | * Returns the index of the Tab to be used after <code>location</code>. |
| 118 | * This will return -1 if there are no tabs after <code>location</code>. |
| 119 | */ |
| 120 | public int getTabIndexAfter(float location) { |
| 121 | int current, min, max; |
| 122 | |
| 123 | min = 0; |
| 124 | max = getTabCount(); |
| 125 | while(min != max) { |
| 126 | current = (max - min) / 2 + min; |
| 127 | if(location > tabs[current].getPosition()) { |
| 128 | if(min == current) |
| 129 | min = max; |
| 130 | else |
| 131 | min = current; |
| 132 | } |
| 133 | else { |
| 134 | if(current == 0 || location > tabs[current - 1].getPosition()) |
| 135 | return current; |
| 136 | max = current; |
| 137 | } |
| 138 | } |
| 139 | // no tabs after the passed in location. |
| 140 | return -1; |
| 141 | } |
| 142 | |
| 143 | /** |
| 144 | * Indicates whether this <code>TabSet</code> is equal to another one. |
| 145 | * @param o the <code>TabSet</code> instance which this instance |
| 146 | * should be compared to. |
| 147 | * @return <code>true</code> if <code>o</code> is the instance of |
| 148 | * <code>TabSet</code>, has the same number of <code>TabStop</code>s |
| 149 | * and they are all equal, <code>false</code> otherwise. |
| 150 | * |
| 151 | * @since 1.5 |
| 152 | */ |
| 153 | public boolean equals(Object o) { |
| 154 | if (o == this) { |
| 155 | return true; |
| 156 | } |
| 157 | if (o instanceof TabSet) { |
| 158 | TabSet ts = (TabSet) o; |
| 159 | int count = getTabCount(); |
| 160 | if (ts.getTabCount() != count) { |
| 161 | return false; |
| 162 | } |
| 163 | for (int i=0; i < count; i++) { |
| 164 | TabStop ts1 = getTab(i); |
| 165 | TabStop ts2 = ts.getTab(i); |
| 166 | if ((ts1 == null && ts2 != null) || |
| 167 | (ts1 != null && !getTab(i).equals(ts.getTab(i)))) { |
| 168 | return false; |
| 169 | } |
| 170 | } |
| 171 | return true; |
| 172 | } |
| 173 | return false; |
| 174 | } |
| 175 | |
| 176 | /** |
| 177 | * Returns a hashcode for this set of TabStops. |
| 178 | * @return a hashcode value for this set of TabStops. |
| 179 | * |
| 180 | * @since 1.5 |
| 181 | */ |
| 182 | public int hashCode() { |
| 183 | if (hashCode == Integer.MAX_VALUE) { |
| 184 | hashCode = 0; |
| 185 | int len = getTabCount(); |
| 186 | for (int i = 0; i < len; i++) { |
| 187 | TabStop ts = getTab(i); |
| 188 | hashCode ^= ts != null ? getTab(i).hashCode() : 0; |
| 189 | } |
| 190 | if (hashCode == Integer.MAX_VALUE) { |
| 191 | hashCode -= 1; |
| 192 | } |
| 193 | } |
| 194 | return hashCode; |
| 195 | } |
| 196 | |
| 197 | /** |
| 198 | * Returns the string representation of the set of tabs. |
| 199 | */ |
| 200 | public String toString() { |
| 201 | int tabCount = getTabCount(); |
| 202 | StringBuffer buffer = new StringBuffer("[ "); |
| 203 | |
| 204 | for(int counter = 0; counter < tabCount; counter++) { |
| 205 | if(counter > 0) |
| 206 | buffer.append(" - "); |
| 207 | buffer.append(getTab(counter).toString()); |
| 208 | } |
| 209 | buffer.append(" ]"); |
| 210 | return buffer.toString(); |
| 211 | } |
| 212 | } |