001 /* TabSet.java --
002 Copyright (C) 2004, 2006, Free Software Foundation, Inc.
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.swing.text;
039
040 import gnu.java.lang.CPStringBuilder;
041
042 import java.io.Serializable;
043
044 /**
045 * A set of tab stops. Instances of this class are immutable.
046 */
047 public class TabSet implements Serializable
048 {
049 /** The serialization UID (compatible with JDK1.5). */
050 private static final long serialVersionUID = 2367703481999080593L;
051
052 /** Storage for the tab stops. */
053 TabStop[] tabs;
054
055 /**
056 * Creates a new <code>TabSet</code> containing the specified tab stops.
057 *
058 * @param t the tab stops (<code>null</code> permitted).
059 */
060 public TabSet(TabStop[] t)
061 {
062 if (t != null)
063 tabs = (TabStop[]) t.clone();
064 else
065 tabs = new TabStop[0];
066 }
067
068 /**
069 * Returns the tab stop with the specified index.
070 *
071 * @param i the index.
072 *
073 * @return The tab stop.
074 *
075 * @throws IllegalArgumentException if <code>i</code> is not in the range
076 * <code>0</code> to <code>getTabCount() - 1</code>.
077 */
078 public TabStop getTab(int i)
079 {
080 if (i < 0 || i >= tabs.length)
081 throw new IllegalArgumentException("Index out of bounds.");
082 return tabs[i];
083 }
084
085 /**
086 * Returns the tab following the specified location.
087 *
088 * @param location the location.
089 *
090 * @return The tab following the specified location (or <code>null</code>).
091 */
092 public TabStop getTabAfter(float location)
093 {
094 int idx = getTabIndexAfter(location);
095 if (idx == -1)
096 return null;
097 else
098 return tabs[idx];
099 }
100
101 /**
102 * Returns the number of tab stops in this tab set.
103 *
104 * @return The number of tab stops in this tab set.
105 */
106 public int getTabCount()
107 {
108 return tabs.length;
109 }
110
111 /**
112 * Returns the index of the specified tab, or -1 if the tab is not found.
113 *
114 * @param tab the tab (<code>null</code> permitted).
115 *
116 * @return The index of the specified tab, or -1.
117 */
118 public int getTabIndex(TabStop tab)
119 {
120 for (int i = 0; i < tabs.length; ++i)
121 if (tabs[i] == tab)
122 return i;
123 return -1;
124 }
125
126 /**
127 * Returns the index of the tab at or after the specified location.
128 *
129 * @param location the tab location.
130 *
131 * @return The index of the tab stop, or -1.
132 */
133 public int getTabIndexAfter(float location)
134 {
135 for (int i = 0; i < tabs.length; i++)
136 {
137 if (location <= tabs[i].getPosition())
138 return i;
139 }
140 return -1;
141 }
142
143 /**
144 * Tests this <code>TabSet</code> for equality with an arbitrary object.
145 *
146 * @param obj the object (<code>null</code> permitted).
147 *
148 * @return <code>true</code> if this <code>TabSet</code> is equal to
149 * <code>obj</code>, and <code>false</code> otherwise.
150 *
151 * @since 1.5
152 */
153 public boolean equals(Object obj)
154 {
155 if (obj == this)
156 return true;
157 if (!(obj instanceof TabSet))
158 return false;
159 TabSet that = (TabSet) obj;
160 int tabCount = getTabCount();
161 if (tabCount != that.getTabCount())
162 return false;
163 for (int i = 0; i < tabCount; i++)
164 {
165 if (!this.getTab(i).equals(that.getTab(i)))
166 return false;
167 }
168 return true;
169 }
170
171 /**
172 * Returns a hash code for this <code>TabSet</code>.
173 *
174 * @return A hash code.
175 *
176 * @since 1.5
177 */
178 public int hashCode()
179 {
180 // this hash code won't match Sun's, but that shouldn't matter...
181 int result = 193;
182 int tabs = getTabCount();
183 for (int i = 0; i < tabs; i++)
184 {
185 TabStop t = getTab(i);
186 if (t != null)
187 result = 37 * result + t.hashCode();
188 }
189 return result;
190 }
191
192 /**
193 * Returns a string representation of this <code>TabSet</code>.
194 *
195 * @return A string representation of this <code>TabSet</code>.
196 */
197 public String toString()
198 {
199 CPStringBuilder sb = new CPStringBuilder();
200 sb.append("[ ");
201 for (int i = 0; i < tabs.length; ++i)
202 {
203 if (i != 0)
204 sb.append(" - ");
205 sb.append(tabs[i].toString());
206 }
207 sb.append(" ]");
208 return sb.toString();
209 }
210 }