Source for javax.swing.text.TabSet

   1: /* TabSet.java --
   2:    Copyright (C) 2004, 2006, Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: package javax.swing.text;
  39: 
  40: import java.io.Serializable;
  41: 
  42: /**
  43:  * A set of tab stops.  Instances of this class are immutable.
  44:  */
  45: public class TabSet implements Serializable
  46: {
  47:   /** The serialization UID (compatible with JDK1.5). */
  48:   private static final long serialVersionUID = 2367703481999080593L;
  49: 
  50:   /** Storage for the tab stops. */
  51:   TabStop[] tabs;
  52: 
  53:   /**
  54:    * Creates a new <code>TabSet</code> containing the specified tab stops.
  55:    * 
  56:    * @param t  the tab stops (<code>null</code> permitted).
  57:    */
  58:   public TabSet(TabStop[] t) 
  59:   {
  60:     if (t != null)
  61:       tabs = (TabStop[]) t.clone();
  62:     else 
  63:       tabs = new TabStop[0];
  64:   }
  65:  
  66:   /**
  67:    * Returns the tab stop with the specified index.
  68:    * 
  69:    * @param i  the index.
  70:    * 
  71:    * @return The tab stop.
  72:    * 
  73:    * @throws IllegalArgumentException if <code>i</code> is not in the range 
  74:    *     <code>0</code> to <code>getTabCount() - 1</code>.
  75:    */
  76:   public TabStop getTab(int i) 
  77:   {
  78:     if (i < 0 || i >= tabs.length)
  79:       throw new IllegalArgumentException("Index out of bounds.");
  80:     return tabs[i];
  81:   }
  82: 
  83:   /**
  84:    * Returns the tab following the specified location.
  85:    * 
  86:    * @param location  the location.
  87:    * 
  88:    * @return The tab following the specified location (or <code>null</code>).
  89:    */
  90:   public TabStop getTabAfter(float location) 
  91:   {
  92:     int idx = getTabIndexAfter(location);
  93:     if (idx == -1)
  94:       return null;
  95:     else
  96:       return tabs[idx];        
  97:   }
  98: 
  99:   /**
 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: }