DefaultKeyedValues


1   /* ===========================================================
2    * JFreeChart : a free chart library for the Java(tm) platform
3    * ===========================================================
4    *
5    * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
6    *
7    * Project Info:  http://www.jfree.org/jfreechart/index.html
8    *
9    * This library is free software; you can redistribute it and/or modify it 
10   * under the terms of the GNU Lesser General Public License as published by 
11   * the Free Software Foundation; either version 2.1 of the License, or 
12   * (at your option) any later version.
13   *
14   * This library is distributed in the hope that it will be useful, but 
15   * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
16   * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
17   * License for more details.
18   *
19   * You should have received a copy of the GNU Lesser General Public License 
20   * along with this library; if not, write to the Free Software Foundation, 
21   * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
22   *
23   * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
24   * in the United States and other countries.]
25   *
26   * -----------------------
27   * DefaultKeyedValues.java
28   * -----------------------
29   * (C) Copyright 2002-2005, by Object Refinery Limited.
30   *
31   * Original Author:  David Gilbert (for Object Refinery Limited);
32   * Contributor(s):   -;
33   *
34   * $Id: DefaultKeyedValues.java,v 1.8 2005/05/19 10:34:07 mungady Exp $
35   *
36   * Changes:
37   * --------
38   * 31-Oct-2002 : Version 1 (DG);
39   * 11-Feb-2003 : Fixed bug in getValue(key) method for unrecognised key (DG);
40   * 05-Mar-2003 : Added methods to sort stored data 'by key' or 'by value' (DG);
41   * 13-Mar-2003 : Implemented Serializable (DG);
42   * 08-Apr-2003 : Modified removeValue(Comparable) method to fix bug 717049 (DG);
43   * 18-Aug-2003 : Implemented Cloneable (DG);
44   * 27-Aug-2003 : Moved SortOrder from org.jfree.data --> org.jfree.util (DG);
45   * 09-Feb-2004 : Modified getIndex() method - see bug report 893256 (DG);
46   * 15-Sep-2004 : Updated clone() method and added PublicCloneable 
47   *               interface (DG);
48   * 25-Nov-2004 : Small update to the clone() implementation (DG);
49   * 24-Feb-2005 : Added methods addValue(Comparable, double) and 
50   *               setValue(Comparable, double) for convenience (DG);
51   *
52   */
53  
54  package org.jfree.data;
55  
56  import java.io.Serializable  ;
57  import java.util.Collections  ;
58  import java.util.Comparator  ;
59  import java.util.Iterator  ;
60  import java.util.List  ;
61  
62  import org.jfree.util.ObjectUtilities;
63  import org.jfree.util.PublicCloneable;
64  import org.jfree.util.SortOrder;
65  
66  /**
67   * An ordered list of (key, value) items.  This class provides a default 
68   * implementation of the {@link KeyedValues} interface.
69   */
70  public class DefaultKeyedValues implements KeyedValues, 
71                                             Cloneable  , PublicCloneable, 
72                                             Serializable   {
73  
74      /** For serialization. */
75      private static final long serialVersionUID = 8468154364608194797L;
76      
77      /** Storage for the data. */
78      private List   data;
79  
80      /**
81       * Creates a new collection (initially empty).
82       */
83      public DefaultKeyedValues() {
84          this.data = new java.util.ArrayList  ();
85      }
86  
87      /**
88       * Returns the number of items (values) in the collection.
89       *
90       * @return The item count.
91       */
92      public int getItemCount() {
93          return this.data.size();
94      }
95  
96      /**
97       * Returns a value.
98       *
99       * @param item  the item of interest (zero-based index).
100      *
101      * @return The value.
102      * 
103      * @throws IndexOutOfBoundsException if <code>item</code> is out of bounds.
104      */
105     public Number   getValue(int item) {
106         Number   result = null;
107         KeyedValue kval = (KeyedValue) this.data.get(item);
108         if (kval != null) {
109             result = kval.getValue();
110         }
111         return result;
112     }
113 
114     /**
115      * Returns a key.
116      *
117      * @param index  the item index (zero-based).
118      *
119      * @return The row key.
120      * 
121      * @throws IndexOutOfBoundsException if <code>item</code> is out of bounds.
122      */
123     public Comparable   getKey(int index) {
124         Comparable   result = null;
125         KeyedValue item = (KeyedValue) this.data.get(index);
126         if (item != null) {
127             result = item.getKey();
128         }
129         return result;
130     }
131 
132     /**
133      * Returns the index for a given key.
134      *
135      * @param key  the key.
136      *
137      * @return The index, or <code>-1</code> if the key is unrecognised.
138      */
139     public int getIndex(Comparable   key) {
140         int i = 0;
141         Iterator   iterator = this.data.iterator();
142         while (iterator.hasNext()) {
143             KeyedValue kv = (KeyedValue) iterator.next();
144             if (kv.getKey().equals(key)) {
145                 return i;
146             }
147             i++;
148         }
149         return -1;  // key not found
150     }
151 
152     /**
153      * Returns the keys for the values in the collection.
154      *
155      * @return The keys (never <code>null</code>).
156      */
157     public List   getKeys() {
158         List   result = new java.util.ArrayList  ();
159         Iterator   iterator = this.data.iterator();
160         while (iterator.hasNext()) {
161             KeyedValue kv = (KeyedValue) iterator.next();
162             result.add(kv.getKey());
163         }
164         return result;
165     }
166 
167     /**
168      * Returns the value for a given key.
169      *
170      * @param key  the key.
171      *
172      * @return The value (possibly <code>null</code>).
173      * 
174      * @throws UnknownKeyException if the key is not recognised.
175      */
176     public Number   getValue(Comparable   key) {
177         int index = getIndex(key);
178         if (index < 0) {
179             throw new UnknownKeyException("Key not found: " + key);
180         }
181         return getValue(index);
182     }
183 
184     /**
185      * Updates an existing value, or adds a new value to the collection.
186      *
187      * @param key  the key (<code>null</code> not permitted).
188      * @param value  the value.
189      */
190     public void addValue(Comparable   key, double value) {
191         addValue(key, new Double  (value)); 
192     }
193     
194     /**
195      * Adds a new value to the collection, or updates an existing value.
196      * This method passes control directly to the 
197      * {@link #setValue(Comparable, Number)} method.
198      *
199      * @param key  the key (<code>null</code> not permitted).
200      * @param value  the value (<code>null</code> permitted).
201      */
202     public void addValue(Comparable   key, Number   value) {
203         setValue(key, value);
204     }
205 
206     /**
207      * Updates an existing value, or adds a new value to the collection.
208      *
209      * @param key  the key (<code>null</code> not permitted).
210      * @param value  the value.
211      */
212     public void setValue(Comparable   key, double value) {
213         setValue(key, new Double  (value));   
214     }
215     
216     /**
217      * Updates an existing value, or adds a new value to the collection.
218      *
219      * @param key  the key (<code>null</code> not permitted).
220      * @param value  the value (<code>null</code> permitted).
221      */
222     public void setValue(Comparable   key, Number   value) {
223         if (key == null) {
224             throw new IllegalArgumentException  ("Null 'key' argument.");
225         }
226         int keyIndex = getIndex(key);
227         if (keyIndex >= 0) {
228             DefaultKeyedValue kv = (DefaultKeyedValue) this.data.get(keyIndex);
229             kv.setValue(value);
230         }
231         else {
232             KeyedValue kv = new DefaultKeyedValue(key, value);
233             this.data.add(kv);
234         }
235     }
236 
237     /**
238      * Removes a value from the collection.
239      *
240      * @param index  the index of the item to remove.
241      */
242     public void removeValue(int index) {
243         this.data.remove(index);
244     }
245 
246     /**
247      * Removes a value from the collection.
248      *
249      * @param key  the item key.
250      * 
251      * @throws UnknownKeyException if the key is not recognised.
252      */
253     public void removeValue(Comparable   key) {
254         int index = getIndex(key);
255         if (index >= 0) {
256             removeValue(index);
257         }
258     }
259 
260     /**
261      * Sorts the items in the list by key.
262      *
263      * @param order  the sort order (<code>null</code> not permitted).
264      */
265     public void sortByKeys(SortOrder order) {
266         Comparator   comparator = new KeyedValueComparator(
267             KeyedValueComparatorType.BY_KEY, order
268         );
269         Collections.sort(this.data, comparator);
270     }
271 
272     /**
273      * Sorts the items in the list by value.  If the list contains 
274      * <code>null</code> values, they will sort to the end of the list, 
275      * irrespective of the sort order.
276      *
277      * @param order  the sort order (<code>null</code> not permitted).
278      */
279     public void sortByValues(SortOrder order) {
280         Comparator   comparator = new KeyedValueComparator(
281             KeyedValueComparatorType.BY_VALUE, order
282         );
283         Collections.sort(this.data, comparator);
284     }
285 
286     /**
287      * Tests if this object is equal to another.
288      *
289      * @param obj  the object (<code>null</code> permitted).
290      *
291      * @return A boolean.
292      */
293     public boolean equals(Object   obj) {
294         if (obj == this) {
295             return true;
296         }
297 
298         if (!(obj instanceof KeyedValues)) {
299             return false;
300         }
301 
302         KeyedValues that = (KeyedValues) obj;
303         int count = getItemCount();
304         if (count != that.getItemCount()) {
305             return false;
306         }
307 
308         for (int i = 0; i < count; i++) {
309             Comparable   k1 = getKey(i);
310             Comparable   k2 = that.getKey(i);
311             if (!k1.equals(k2)) {
312                 return false;
313             }
314             Number   v1 = getValue(i);
315             Number   v2 = that.getValue(i);
316             if (v1 == null) {
317                 if (v2 != null) {
318                     return false;
319                 }
320             }
321             else {
322                 if (!v1.equals(v2)) {
323                     return false;
324                 }
325             }
326         }
327         return true;
328     }
329 
330     /**
331      * Returns a hash code.
332      * 
333      * @return A hash code.
334      */
335     public int hashCode() {
336         return (this.data != null ? this.data.hashCode() : 0);
337     }
338 
339     /**
340      * Returns a clone.
341      * 
342      * @return A clone.
343      * 
344      * @throws CloneNotSupportedException  this class will not throw this 
345      *         exception, but subclasses might.
346      */
347     public Object   clone() throws CloneNotSupportedException   {
348         DefaultKeyedValues clone = (DefaultKeyedValues) super.clone();
349         clone.data = (List  ) ObjectUtilities.deepClone(this.data);
350         return clone;    
351     }
352     
353 }
354
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