1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18
19 package org.apache.commons.beanutils;
20
21 import java.io.Serializable;
22 import java.lang.reflect.InvocationTargetException;
23
24
25 /**
26 * <p>Implementation of <code>DynaBean</code> that wraps a standard JavaBean
27 * instance, so that DynaBean APIs can be used to access its properties.</p>
28 *
29 * <p>
30 * The most common use cases for this class involve wrapping an existing java bean.
31 * (This makes it different from the typical use cases for other <code>DynaBean</code>'s.)
32 * For example:
33 * </p>
34 * <code><pre>
35 * Object aJavaBean = ...;
36 * ...
37 * DynaBean db = new WrapDynaBean(aJavaBean);
38 * ...
39 * </pre></code>
40 *
41 * <p><strong>IMPLEMENTATION NOTE</strong> - This implementation does not
42 * support the <code>contains()</code> and <code>remove()</code> methods.</p>
43 *
44 * @version $Id$
45 */
46
47 public class WrapDynaBean implements DynaBean, Serializable {
48
49
50 // ---------------------------------------------------------- Constructors
51
52
53 /**
54 * Construct a new <code>DynaBean</code> associated with the specified
55 * JavaBean instance.
56 *
57 * @param instance JavaBean instance to be wrapped
58 */
59 public WrapDynaBean(final Object instance) {
60
61 this(instance, null);
62
63 }
64
65 /**
66 * Creates a new instance of {@code WrapDynaBean}, associates it with the specified
67 * JavaBean instance, and initializes the bean's {@code DynaClass}. Using this
68 * constructor this {@code WrapDynaBean} instance can be assigned a class which has
69 * been configured externally. If no {@code WrapDynaClass} is provided, a new one is
70 * created using a standard mechanism.
71 *
72 * @param instance JavaBean instance to be wrapped
73 * @param cls the optional {@code WrapDynaClass} to be used for this bean
74 * @since 1.9
75 */
76 public WrapDynaBean(final Object instance, final WrapDynaClass cls) {
77
78 this.instance = instance;
79 this.dynaClass = (cls != null) ? cls : (WrapDynaClass) getDynaClass();
80
81 }
82
83 // ---------------------------------------------------- Instance Variables
84
85
86 /**
87 * The <code>DynaClass</code> "base class" that this DynaBean
88 * is associated with.
89 */
90 protected transient WrapDynaClass dynaClass = null;
91
92
93 /**
94 * The JavaBean instance wrapped by this WrapDynaBean.
95 */
96 protected Object instance = null;
97
98
99 // ------------------------------------------------------ DynaBean Methods
100
101
102 /**
103 * Does the specified mapped property contain a value for the specified
104 * key value?
105 *
106 * @param name Name of the property to check
107 * @param key Name of the key to check
108 * @return <code>true<code> if the mapped property contains a value for
109 * the specified key, otherwise <code>false</code>
110 *
111 * @throws IllegalArgumentException if there is no property
112 * of the specified name
113 */
114 public boolean contains(final String name, final String key) {
115
116 throw new UnsupportedOperationException
117 ("WrapDynaBean does not support contains()");
118
119 }
120
121
122 /**
123 * Return the value of a simple property with the specified name.
124 *
125 * @param name Name of the property whose value is to be retrieved
126 * @return The property's value
127 *
128 * @throws IllegalArgumentException if there is no property
129 * of the specified name
130 */
131 public Object get(final String name) {
132
133 Object value = null;
134 try {
135 value = getPropertyUtils().getSimpleProperty(instance, name);
136 } catch (final InvocationTargetException ite) {
137 final Throwable cause = ite.getTargetException();
138 throw new IllegalArgumentException
139 ("Error reading property '" + name +
140 "' nested exception - " + cause);
141 } catch (final Throwable t) {
142 throw new IllegalArgumentException
143 ("Error reading property '" + name +
144 "', exception - " + t);
145 }
146 return (value);
147
148 }
149
150
151 /**
152 * Return the value of an indexed property with the specified name.
153 *
154 * @param name Name of the property whose value is to be retrieved
155 * @param index Index of the value to be retrieved
156 * @return The indexed property's value
157 *
158 * @throws IllegalArgumentException if there is no property
159 * of the specified name
160 * @throws IllegalArgumentException if the specified property
161 * exists, but is not indexed
162 * @throws IndexOutOfBoundsException if the specified index
163 * is outside the range of the underlying property
164 * @throws NullPointerException if no array or List has been
165 * initialized for this property
166 */
167 public Object get(final String name, final int index) {
168
169 Object value = null;
170 try {
171 value = getPropertyUtils().getIndexedProperty(instance, name, index);
172 } catch (final IndexOutOfBoundsException e) {
173 throw e;
174 } catch (final InvocationTargetException ite) {
175 final Throwable cause = ite.getTargetException();
176 throw new IllegalArgumentException
177 ("Error reading indexed property '" + name +
178 "' nested exception - " + cause);
179 } catch (final Throwable t) {
180 throw new IllegalArgumentException
181 ("Error reading indexed property '" + name +
182 "', exception - " + t);
183 }
184 return (value);
185
186 }
187
188
189 /**
190 * Return the value of a mapped property with the specified name,
191 * or <code>null</code> if there is no value for the specified key.
192 *
193 * @param name Name of the property whose value is to be retrieved
194 * @param key Key of the value to be retrieved
195 * @return The mapped property's value
196 *
197 * @throws IllegalArgumentException if there is no property
198 * of the specified name
199 * @throws IllegalArgumentException if the specified property
200 * exists, but is not mapped
201 */
202 public Object get(final String name, final String key) {
203
204 Object value = null;
205 try {
206 value = getPropertyUtils().getMappedProperty(instance, name, key);
207 } catch (final InvocationTargetException ite) {
208 final Throwable cause = ite.getTargetException();
209 throw new IllegalArgumentException
210 ("Error reading mapped property '" + name +
211 "' nested exception - " + cause);
212 } catch (final Throwable t) {
213 throw new IllegalArgumentException
214 ("Error reading mapped property '" + name +
215 "', exception - " + t);
216 }
217 return (value);
218
219 }
220
221
222 /**
223 * Return the <code>DynaClass</code> instance that describes the set of
224 * properties available for this DynaBean.
225 * @return The associated DynaClass
226 */
227 public DynaClass getDynaClass() {
228
229 if (dynaClass == null) {
230 dynaClass = WrapDynaClass.createDynaClass(instance.getClass());
231 }
232
233 return (this.dynaClass);
234
235 }
236
237
238 /**
239 * Remove any existing value for the specified key on the
240 * specified mapped property.
241 *
242 * @param name Name of the property for which a value is to
243 * be removed
244 * @param key Key of the value to be removed
245 *
246 * @throws IllegalArgumentException if there is no property
247 * of the specified name
248 */
249 public void remove(final String name, final String key) {
250
251
252 throw new UnsupportedOperationException
253 ("WrapDynaBean does not support remove()");
254
255 }
256
257
258 /**
259 * Set the value of a simple property with the specified name.
260 *
261 * @param name Name of the property whose value is to be set
262 * @param value Value to which this property is to be set
263 *
264 * @throws ConversionException if the specified value cannot be
265 * converted to the type required for this property
266 * @throws IllegalArgumentException if there is no property
267 * of the specified name
268 * @throws NullPointerException if an attempt is made to set a
269 * primitive property to null
270 */
271 public void set(final String name, final Object value) {
272
273 try {
274 getPropertyUtils().setSimpleProperty(instance, name, value);
275 } catch (final InvocationTargetException ite) {
276 final Throwable cause = ite.getTargetException();
277 throw new IllegalArgumentException
278 ("Error setting property '" + name +
279 "' nested exception -" + cause);
280 } catch (final Throwable t) {
281 throw new IllegalArgumentException
282 ("Error setting property '" + name +
283 "', exception - " + t);
284 }
285
286 }
287
288
289 /**
290 * Set the value of an indexed property with the specified name.
291 *
292 * @param name Name of the property whose value is to be set
293 * @param index Index of the property to be set
294 * @param value Value to which this property is to be set
295 *
296 * @throws ConversionException if the specified value cannot be
297 * converted to the type required for this property
298 * @throws IllegalArgumentException if there is no property
299 * of the specified name
300 * @throws IllegalArgumentException if the specified property
301 * exists, but is not indexed
302 * @throws IndexOutOfBoundsException if the specified index
303 * is outside the range of the underlying property
304 */
305 public void set(final String name, final int index, final Object value) {
306
307 try {
308 getPropertyUtils().setIndexedProperty(instance, name, index, value);
309 } catch (final IndexOutOfBoundsException e) {
310 throw e;
311 } catch (final InvocationTargetException ite) {
312 final Throwable cause = ite.getTargetException();
313 throw new IllegalArgumentException
314 ("Error setting indexed property '" + name +
315 "' nested exception - " + cause);
316 } catch (final Throwable t) {
317 throw new IllegalArgumentException
318 ("Error setting indexed property '" + name +
319 "', exception - " + t);
320 }
321
322 }
323
324
325 /**
326 * Set the value of a mapped property with the specified name.
327 *
328 * @param name Name of the property whose value is to be set
329 * @param key Key of the property to be set
330 * @param value Value to which this property is to be set
331 *
332 * @throws ConversionException if the specified value cannot be
333 * converted to the type required for this property
334 * @throws IllegalArgumentException if there is no property
335 * of the specified name
336 * @throws IllegalArgumentException if the specified property
337 * exists, but is not mapped
338 */
339 public void set(final String name, final String key, final Object value) {
340
341 try {
342 getPropertyUtils().setMappedProperty(instance, name, key, value);
343 } catch (final InvocationTargetException ite) {
344 final Throwable cause = ite.getTargetException();
345 throw new IllegalArgumentException
346 ("Error setting mapped property '" + name +
347 "' nested exception - " + cause);
348 } catch (final Throwable t) {
349 throw new IllegalArgumentException
350 ("Error setting mapped property '" + name +
351 "', exception - " + t);
352 }
353
354 }
355
356 /**
357 * Gets the bean instance wrapped by this DynaBean.
358 * For most common use cases,
359 * this object should already be known
360 * and this method safely be ignored.
361 * But some creators of frameworks using <code>DynaBean</code>'s may
362 * find this useful.
363 *
364 * @return the java bean Object wrapped by this <code>DynaBean</code>
365 */
366 public Object getInstance() {
367 return instance;
368 }
369
370
371 // ------------------------------------------------------ Protected Methods
372
373
374 /**
375 * Return the property descriptor for the specified property name.
376 *
377 * @param name Name of the property for which to retrieve the descriptor
378 * @return The descriptor for the specified property
379 *
380 * @throws IllegalArgumentException if this is not a valid property
381 * name for our DynaClass
382 */
383 protected DynaProperty getDynaProperty(final String name) {
384
385 final DynaProperty descriptor = getDynaClass().getDynaProperty(name);
386 if (descriptor == null) {
387 throw new IllegalArgumentException
388 ("Invalid property name '" + name + "'");
389 }
390 return (descriptor);
391
392 }
393
394 /**
395 * Returns the {@code PropertyUtilsBean} instance to be used for accessing properties.
396 * If available, this object is obtained from the associated {@code WrapDynaClass}.
397 *
398 * @return the associated {@code PropertyUtilsBean}
399 */
400 private PropertyUtilsBean getPropertyUtils() {
401
402 PropertyUtilsBean propUtils = null;
403 if (dynaClass != null) {
404 propUtils = dynaClass.getPropertyUtilsBean();
405 }
406 return (propUtils != null) ? propUtils : PropertyUtilsBean.getInstance();
407
408 }
409 }