001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018
019package org.apache.commons.beanutils;
020
021import java.io.Serializable;
022import java.lang.reflect.InvocationTargetException;
023
024
025/**
026 * <p>Implementation of <code>DynaBean</code> that wraps a standard JavaBean
027 * instance, so that DynaBean APIs can be used to access its properties.</p>
028 *
029 * <p>
030 * The most common use cases for this class involve wrapping an existing java bean.
031 * (This makes it different from the typical use cases for other <code>DynaBean</code>'s.) 
032 * For example:
033 * </p>
034 * <code><pre>
035 *  Object aJavaBean = ...;
036 *  ...
037 *  DynaBean db = new WrapDynaBean(aJavaBean);
038 *  ...
039 * </pre></code>
040 *
041 * <p><strong>IMPLEMENTATION NOTE</strong> - This implementation does not
042 * support the <code>contains()</code> and <code>remove()</code> methods.</p>
043 *
044 * @author Craig McClanahan
045 * @version $Revision: 926529 $ $Date: 2010-03-23 11:44:24 +0000 (Tue, 23 Mar 2010) $
046 */
047
048public class WrapDynaBean implements DynaBean, Serializable {
049
050
051    // ---------------------------------------------------------- Constructors
052
053
054    /**
055     * Construct a new <code>DynaBean</code> associated with the specified
056     * JavaBean instance.
057     *
058     * @param instance JavaBean instance to be wrapped
059     */
060    public WrapDynaBean(Object instance) {
061
062        super();
063        this.instance = instance;
064        this.dynaClass = (WrapDynaClass)getDynaClass();
065
066    }
067
068
069    // ---------------------------------------------------- Instance Variables
070
071
072    /**
073     * The <code>DynaClass</code> "base class" that this DynaBean
074     * is associated with.
075     */
076    protected transient WrapDynaClass dynaClass = null;
077
078
079    /**
080     * The JavaBean instance wrapped by this WrapDynaBean.
081     */
082    protected Object instance = null;
083
084
085    // ------------------------------------------------------ DynaBean Methods
086
087
088    /**
089     * Does the specified mapped property contain a value for the specified
090     * key value?
091     *
092     * @param name Name of the property to check
093     * @param key Name of the key to check
094     * @return <code>true<code> if the mapped property contains a value for
095     * the specified key, otherwise <code>false</code>
096     *
097     * @exception IllegalArgumentException if there is no property
098     *  of the specified name
099     */
100    public boolean contains(String name, String key) {
101
102        throw new UnsupportedOperationException
103                ("WrapDynaBean does not support contains()");
104
105    }
106
107
108    /**
109     * Return the value of a simple property with the specified name.
110     *
111     * @param name Name of the property whose value is to be retrieved
112     * @return The property's value
113     *
114     * @exception IllegalArgumentException if there is no property
115     *  of the specified name
116     */
117    public Object get(String name) {
118
119        Object value = null;
120        try {
121            value = PropertyUtils.getSimpleProperty(instance, name);
122        } catch (InvocationTargetException ite) {
123            Throwable cause = ite.getTargetException();
124            throw new IllegalArgumentException
125                    ("Error reading property '" + name +
126                              "' nested exception - " + cause);
127        } catch (Throwable t) {
128            throw new IllegalArgumentException
129                    ("Error reading property '" + name +
130                              "', exception - " + t);
131        }
132        return (value);
133
134    }
135
136
137    /**
138     * Return the value of an indexed property with the specified name.
139     *
140     * @param name Name of the property whose value is to be retrieved
141     * @param index Index of the value to be retrieved
142     * @return The indexed property's value
143     *
144     * @exception IllegalArgumentException if there is no property
145     *  of the specified name
146     * @exception IllegalArgumentException if the specified property
147     *  exists, but is not indexed
148     * @exception IndexOutOfBoundsException if the specified index
149     *  is outside the range of the underlying property
150     * @exception NullPointerException if no array or List has been
151     *  initialized for this property
152     */
153    public Object get(String name, int index) {
154
155        Object value = null;
156        try {
157            value = PropertyUtils.getIndexedProperty(instance, name, index);
158        } catch (IndexOutOfBoundsException e) {
159            throw e;
160        } catch (InvocationTargetException ite) {
161            Throwable cause = ite.getTargetException();
162            throw new IllegalArgumentException
163                    ("Error reading indexed property '" + name +
164                              "' nested exception - " + cause);
165        } catch (Throwable t) {
166            throw new IllegalArgumentException
167                    ("Error reading indexed property '" + name +
168                              "', exception - " + t);
169        }
170        return (value);
171
172    }
173
174
175    /**
176     * Return the value of a mapped property with the specified name,
177     * or <code>null</code> if there is no value for the specified key.
178     *
179     * @param name Name of the property whose value is to be retrieved
180     * @param key Key of the value to be retrieved
181     * @return The mapped property's value
182     *
183     * @exception IllegalArgumentException if there is no property
184     *  of the specified name
185     * @exception IllegalArgumentException if the specified property
186     *  exists, but is not mapped
187     */
188    public Object get(String name, String key) {
189
190        Object value = null;
191        try {
192            value = PropertyUtils.getMappedProperty(instance, name, key);
193        } catch (InvocationTargetException ite) {
194            Throwable cause = ite.getTargetException();
195            throw new IllegalArgumentException
196                    ("Error reading mapped property '" + name +
197                              "' nested exception - " + cause);
198        } catch (Throwable t) {
199            throw new IllegalArgumentException
200                    ("Error reading mapped property '" + name +
201                              "', exception - " + t);
202        }
203        return (value);
204
205    }
206
207
208    /**
209     * Return the <code>DynaClass</code> instance that describes the set of
210     * properties available for this DynaBean.
211     * @return The associated DynaClass
212     */
213    public DynaClass getDynaClass() {
214
215        if (dynaClass == null) {
216            dynaClass = WrapDynaClass.createDynaClass(instance.getClass());
217        }
218
219        return (this.dynaClass);
220
221    }
222
223
224    /**
225     * Remove any existing value for the specified key on the
226     * specified mapped property.
227     *
228     * @param name Name of the property for which a value is to
229     *  be removed
230     * @param key Key of the value to be removed
231     *
232     * @exception IllegalArgumentException if there is no property
233     *  of the specified name
234     */
235    public void remove(String name, String key) {
236
237
238        throw new UnsupportedOperationException
239                ("WrapDynaBean does not support remove()");
240
241    }
242
243
244    /**
245     * Set the value of a simple property with the specified name.
246     *
247     * @param name Name of the property whose value is to be set
248     * @param value Value to which this property is to be set
249     *
250     * @exception ConversionException if the specified value cannot be
251     *  converted to the type required for this property
252     * @exception IllegalArgumentException if there is no property
253     *  of the specified name
254     * @exception NullPointerException if an attempt is made to set a
255     *  primitive property to null
256     */
257    public void set(String name, Object value) {
258
259        try {
260            PropertyUtils.setSimpleProperty(instance, name, value);
261        } catch (InvocationTargetException ite) {
262            Throwable cause = ite.getTargetException();
263            throw new IllegalArgumentException
264                    ("Error setting property '" + name +
265                              "' nested exception -" + cause);
266        } catch (Throwable t) {
267            throw new IllegalArgumentException
268                    ("Error setting property '" + name +
269                              "', exception - " + t);
270        }
271
272    }
273
274
275    /**
276     * Set the value of an indexed property with the specified name.
277     *
278     * @param name Name of the property whose value is to be set
279     * @param index Index of the property to be set
280     * @param value Value to which this property is to be set
281     *
282     * @exception ConversionException if the specified value cannot be
283     *  converted to the type required for this property
284     * @exception IllegalArgumentException if there is no property
285     *  of the specified name
286     * @exception IllegalArgumentException if the specified property
287     *  exists, but is not indexed
288     * @exception IndexOutOfBoundsException if the specified index
289     *  is outside the range of the underlying property
290     */
291    public void set(String name, int index, Object value) {
292
293        try {
294            PropertyUtils.setIndexedProperty(instance, name, index, value);
295        } catch (IndexOutOfBoundsException e) {
296            throw e;
297        } catch (InvocationTargetException ite) {
298            Throwable cause = ite.getTargetException();
299            throw new IllegalArgumentException
300                    ("Error setting indexed property '" + name +
301                              "' nested exception - " + cause);
302        } catch (Throwable t) {
303            throw new IllegalArgumentException
304                    ("Error setting indexed property '" + name +
305                              "', exception - " + t);
306        }
307
308    }
309
310
311    /**
312     * Set the value of a mapped property with the specified name.
313     *
314     * @param name Name of the property whose value is to be set
315     * @param key Key of the property to be set
316     * @param value Value to which this property is to be set
317     *
318     * @exception ConversionException if the specified value cannot be
319     *  converted to the type required for this property
320     * @exception IllegalArgumentException if there is no property
321     *  of the specified name
322     * @exception IllegalArgumentException if the specified property
323     *  exists, but is not mapped
324     */
325    public void set(String name, String key, Object value) {
326
327        try {
328            PropertyUtils.setMappedProperty(instance, name, key, value);
329        } catch (InvocationTargetException ite) {
330            Throwable cause = ite.getTargetException();
331            throw new IllegalArgumentException
332                    ("Error setting mapped property '" + name +
333                              "' nested exception - " + cause);
334        } catch (Throwable t) {
335            throw new IllegalArgumentException
336                    ("Error setting mapped property '" + name +
337                              "', exception - " + t);
338        }
339
340    }
341
342    /** 
343     * Gets the bean instance wrapped by this DynaBean.
344     * For most common use cases, 
345     * this object should already be known 
346     * and this method safely be ignored.
347     * But some creators of frameworks using <code>DynaBean</code>'s may 
348     * find this useful.
349     *
350     * @return the java bean Object wrapped by this <code>DynaBean</code>
351     */
352    public Object getInstance() {
353        return instance;
354    }
355
356
357    // ------------------------------------------------------ Protected Methods
358
359
360    /**
361     * Return the property descriptor for the specified property name.
362     *
363     * @param name Name of the property for which to retrieve the descriptor
364     * @return The descriptor for the specified property
365     *
366     * @exception IllegalArgumentException if this is not a valid property
367     *  name for our DynaClass
368     */
369    protected DynaProperty getDynaProperty(String name) {
370
371        DynaProperty descriptor = getDynaClass().getDynaProperty(name);
372        if (descriptor == null) {
373            throw new IllegalArgumentException
374                    ("Invalid property name '" + name + "'");
375        }
376        return (descriptor);
377
378    }
379
380
381}