001    /* FieldPosition.java -- Keeps track of field positions while formatting
002       Copyright (C) 1998, 1999, 2001, 2005  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    
039    package java.text;
040    
041    /**
042     * This class is used by the java.text formatting classes to track
043     * field positions.  A field position is defined by an identifier value
044     * and begin and end index positions.  The formatting classes in java.text
045     * typically define constant values for the field identifiers.
046     *
047     * @author Aaron M. Renn (arenn@urbanophile.com)
048     * @author Per Bothner (bothner@cygnus.com)
049     */
050    public class FieldPosition
051    {
052      /**
053       * This is the field identifier value.
054       */
055      private int field_id;
056    
057      /**
058       * This is the beginning index of the field.
059       */
060      private int begin;
061    
062      /**
063       * This is the ending index of the field.
064       */
065      private int end;
066    
067      /**
068       * This is the field attribute value.
069       */
070      private Format.Field field_attribute;
071    
072      /**
073       * This method initializes a new instance of <code>FieldPosition</code>
074       * to have the specified field attribute. The attribute will be used as
075       * an id. It is formally equivalent to calling FieldPosition(field, -1).
076       *
077       * @param field The field format attribute.
078       */
079      public FieldPosition (Format.Field field)
080      {
081        this(field, -1);
082      }
083    
084      /**
085       * This method initializes a new instance of <code>FieldPosition</code>
086       * to have the specified field attribute. The attribute will be used as
087       * an id is non null. The integer field id is only used if the Format.Field
088       * attribute is not used by the formatter.
089       *
090       * @param field The field format attribute.
091       * @param field_id The field identifier value.
092       */
093      public FieldPosition (Format.Field field, int field_id)
094      {
095        this.field_attribute = field;
096        this.field_id = field_id;
097      }
098    
099      /**
100       * This method initializes a new instance of <code>FieldPosition</code> to
101       * have the specified field id.
102       *
103       * @param field_id The field identifier value.
104       */
105      public FieldPosition (int field_id)
106      {
107        this.field_id = field_id;
108      }
109    
110      /**
111       * This method returns the field identifier value for this object.
112       *
113       * @return The field identifier.
114       */
115      public int getField ()
116      {
117        return field_id;
118      }
119    
120      public Format.Field getFieldAttribute ()
121      {
122        return field_attribute;
123      }
124    
125      /**
126       * This method returns the beginning index for this field.
127       *
128       * @return The beginning index.
129       */
130      public int getBeginIndex ()
131      {
132        return begin;
133      }
134    
135      /**
136       * This method sets the beginning index of this field to the specified value.
137       *
138       * @param begin The new beginning index.
139       */
140      public void setBeginIndex (int begin)
141      {
142        this.begin = begin;
143      }
144    
145      /**
146       * This method returns the ending index for the field.
147       *
148       * @return The ending index.
149       */
150      public int getEndIndex ()
151      {
152        return end;
153      }
154    
155      /**
156       * This method sets the ending index of this field to the specified value.
157       *
158       * @param end The new ending index.
159       */
160      public void setEndIndex (int end)
161      {
162        this.end = end;
163      }
164    
165      /**
166       * This method tests this object for equality against the specified object.
167       * The objects will be considered equal if and only if:
168       * <p>
169       * <ul>
170       * <li>The specified object is not <code>null</code>.
171       * <li>The specified object has the same class as this object.
172       * <li>The specified object has the same field identifier, field attribute
173       * and beginning and ending index as this object.
174       * </ul>
175       *
176       * @param obj The object to test for equality to this object.
177       *
178       * @return <code>true</code> if the specified object is equal to
179       * this object, <code>false</code> otherwise.
180       */
181      public boolean equals (Object obj)
182      {
183        if (this == obj)
184          return true;
185    
186        if (obj == null || obj.getClass() != this.getClass())
187          return false;
188    
189        FieldPosition fp = (FieldPosition) obj;
190        return (field_id == fp.field_id
191                && (field_attribute == fp.field_attribute
192                    || (field_attribute != null
193                        && field_attribute.equals(fp.field_attribute)))
194                && begin == fp.begin
195                && end == fp.end);
196      }
197    
198    
199      /**
200       * This method returns a hash value for this object
201       *
202       * @return A hash value for this object.
203       */
204      public int hashCode ()
205      {
206        int hash = 5;
207    
208        hash = 31 * hash + field_id;
209        hash = 31 * hash + begin;
210        hash = 31 * hash + end;
211        hash = 31 * hash +
212          (null == field_attribute ? 0 : field_attribute.hashCode());
213    
214        return hash;
215      }
216    
217      /**
218       * This method returns a <code>String</code> representation of this
219       * object.
220       *
221       * @return A <code>String</code> representation of this object.
222       */
223      public String toString ()
224      {
225        return (getClass ().getName ()
226                + "[field=" + getField ()
227                + ",attribute=" + getFieldAttribute ()
228                + ",beginIndex=" + getBeginIndex ()
229                + ",endIndex=" + getEndIndex ()
230                + "]");
231      }
232    }