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