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
021
022import java.io.Serializable;
023import java.lang.reflect.Array;
024import java.util.HashMap;
025import java.util.List;
026import java.util.Map;
027
028
029/**
030 * <p>Minimal implementation of the <code>DynaBean</code> interface.  Can be
031 * used as a convenience base class for more sophisticated implementations.</p>
032 *
033 * <p><strong>IMPLEMENTATION NOTE</strong> - Instances of this class that are
034 * accessed from multiple threads simultaneously need to be synchronized.</p>
035 *
036 * <p><strong>IMPLEMENTATION NOTE</strong> - Instances of this class can be
037 * successfully serialized and deserialized <strong>ONLY</strong> if all
038 * property values are <code>Serializable</code>.</p>
039 *
040 * @version $Id$
041 */
042
043public class BasicDynaBean implements DynaBean, Serializable {
044
045
046    // ---------------------------------------------------------- Constructors
047
048
049    /**
050     * Construct a new <code>DynaBean</code> associated with the specified
051     * <code>DynaClass</code> instance.
052     *
053     * @param dynaClass The DynaClass we are associated with
054     */
055    public BasicDynaBean(final DynaClass dynaClass) {
056
057        super();
058        this.dynaClass = dynaClass;
059
060    }
061
062
063    // ---------------------------------------------------- Instance Variables
064
065
066    /**
067     * The <code>DynaClass</code> "base class" that this DynaBean
068     * is associated with.
069     */
070    protected DynaClass dynaClass = null;
071
072
073    /**
074     * The set of property values for this DynaBean, keyed by property name.
075     */
076    protected HashMap<String, Object> values = new HashMap<String, Object>();
077
078    /** Map decorator for this DynaBean */
079    private transient Map<String, Object> mapDecorator;
080
081    /**
082     * Return a Map representation of this DynaBean.
083     * </p>
084     * This, for example, could be used in JSTL in the following way to access
085     * a DynaBean's <code>fooProperty</code>:
086     * <ul><li><code>${myDynaBean.<b>map</b>.fooProperty}</code></li></ul>
087     *
088     * @return a Map representation of this DynaBean
089     * @since 1.8.0
090     */
091    public Map<String, Object> getMap() {
092
093        // cache the Map
094        if (mapDecorator == null) {
095            mapDecorator = new DynaBeanPropertyMapDecorator(this);
096        }
097        return mapDecorator;
098
099    }
100
101    // ------------------------------------------------------ DynaBean Methods
102
103
104    /**
105     * Does the specified mapped property contain a value for the specified
106     * key value?
107     *
108     * @param name Name of the property to check
109     * @param key Name of the key to check
110     * @return <code>true</code> if the mapped property contains a value for
111     * the specified key, otherwise <code>false</code>
112     *
113     * @throws IllegalArgumentException if there is no property
114     *  of the specified name
115     */
116    public boolean contains(final String name, final String key) {
117
118        final Object value = values.get(name);
119        if (value == null) {
120            throw new NullPointerException
121                    ("No mapped value for '" + name + "(" + key + ")'");
122        } else if (value instanceof Map) {
123            return (((Map<?, ?>) value).containsKey(key));
124        } else {
125            throw new IllegalArgumentException
126                    ("Non-mapped property for '" + name + "(" + key + ")'");
127        }
128
129    }
130
131
132    /**
133     * Return the value of a simple property with the specified name.
134     *
135     * @param name Name of the property whose value is to be retrieved
136     * @return The property's value
137     *
138     * @throws IllegalArgumentException if there is no property
139     *  of the specified name
140     */
141    public Object get(final String name) {
142
143        // Return any non-null value for the specified property
144        final Object value = values.get(name);
145        if (value != null) {
146            return (value);
147        }
148
149        // Return a null value for a non-primitive property
150        final Class<?> type = getDynaProperty(name).getType();
151        if (!type.isPrimitive()) {
152            return (value);
153        }
154
155        // Manufacture default values for primitive properties
156        if (type == Boolean.TYPE) {
157            return (Boolean.FALSE);
158        } else if (type == Byte.TYPE) {
159            return (new Byte((byte) 0));
160        } else if (type == Character.TYPE) {
161            return (new Character((char) 0));
162        } else if (type == Double.TYPE) {
163            return (new Double(0.0));
164        } else if (type == Float.TYPE) {
165            return (new Float((float) 0.0));
166        } else if (type == Integer.TYPE) {
167            return (new Integer(0));
168        } else if (type == Long.TYPE) {
169            return (new Long(0));
170        } else if (type == Short.TYPE) {
171            return (new Short((short) 0));
172        } else {
173            return (null);
174        }
175
176    }
177
178
179    /**
180     * Return the value of an indexed property with the specified name.
181     *
182     * @param name Name of the property whose value is to be retrieved
183     * @param index Index of the value to be retrieved
184     * @return The indexed property's value
185     *
186     * @throws IllegalArgumentException if there is no property
187     *  of the specified name
188     * @throws IllegalArgumentException if the specified property
189     *  exists, but is not indexed
190     * @throws IndexOutOfBoundsException if the specified index
191     *  is outside the range of the underlying property
192     * @throws NullPointerException if no array or List has been
193     *  initialized for this property
194     */
195    public Object get(final String name, final int index) {
196
197        final Object value = values.get(name);
198        if (value == null) {
199            throw new NullPointerException
200                    ("No indexed value for '" + name + "[" + index + "]'");
201        } else if (value.getClass().isArray()) {
202            return (Array.get(value, index));
203        } else if (value instanceof List) {
204            return ((List<?>) value).get(index);
205        } else {
206            throw new IllegalArgumentException
207                    ("Non-indexed property for '" + name + "[" + index + "]'");
208        }
209
210    }
211
212
213    /**
214     * Return the value of a mapped property with the specified name,
215     * or <code>null</code> if there is no value for the specified key.
216     *
217     * @param name Name of the property whose value is to be retrieved
218     * @param key Key of the value to be retrieved
219     * @return The mapped property's value
220     *
221     * @throws IllegalArgumentException if there is no property
222     *  of the specified name
223     * @throws IllegalArgumentException if the specified property
224     *  exists, but is not mapped
225     */
226    public Object get(final String name, final String key) {
227
228        final Object value = values.get(name);
229        if (value == null) {
230            throw new NullPointerException
231                    ("No mapped value for '" + name + "(" + key + ")'");
232        } else if (value instanceof Map) {
233            return (((Map<?, ?>) value).get(key));
234        } else {
235            throw new IllegalArgumentException
236                    ("Non-mapped property for '" + name + "(" + key + ")'");
237        }
238
239    }
240
241
242    /**
243     * Return the <code>DynaClass</code> instance that describes the set of
244     * properties available for this DynaBean.
245     *
246     * @return The associated DynaClass
247     */
248    public DynaClass getDynaClass() {
249
250        return (this.dynaClass);
251
252    }
253
254
255    /**
256     * Remove any existing value for the specified key on the
257     * specified mapped property.
258     *
259     * @param name Name of the property for which a value is to
260     *  be removed
261     * @param key Key of the value to be removed
262     *
263     * @throws IllegalArgumentException if there is no property
264     *  of the specified name
265     */
266    public void remove(final String name, final String key) {
267
268        final Object value = values.get(name);
269        if (value == null) {
270            throw new NullPointerException
271                    ("No mapped value for '" + name + "(" + key + ")'");
272        } else if (value instanceof Map) {
273            ((Map<?, ?>) value).remove(key);
274        } else {
275            throw new IllegalArgumentException
276                    ("Non-mapped property for '" + name + "(" + key + ")'");
277        }
278
279    }
280
281
282    /**
283     * Set the value of a simple property with the specified name.
284     *
285     * @param name Name of the property whose value is to be set
286     * @param value Value to which this property is to be set
287     *
288     * @throws ConversionException if the specified value cannot be
289     *  converted to the type required for this property
290     * @throws IllegalArgumentException if there is no property
291     *  of the specified name
292     * @throws NullPointerException if an attempt is made to set a
293     *  primitive property to null
294     */
295    public void set(final String name, final Object value) {
296
297        final DynaProperty descriptor = getDynaProperty(name);
298        if (value == null) {
299            if (descriptor.getType().isPrimitive()) {
300                throw new NullPointerException
301                        ("Primitive value for '" + name + "'");
302            }
303        } else if (!isAssignable(descriptor.getType(), value.getClass())) {
304            throw new ConversionException
305                    ("Cannot assign value of type '" +
306                    value.getClass().getName() +
307                    "' to property '" + name + "' of type '" +
308                    descriptor.getType().getName() + "'");
309        }
310        values.put(name, value);
311
312    }
313
314
315    /**
316     * Set the value of an indexed property with the specified name.
317     *
318     * @param name Name of the property whose value is to be set
319     * @param index Index of the property to be set
320     * @param value Value to which this property is to be set
321     *
322     * @throws ConversionException if the specified value cannot be
323     *  converted to the type required for this property
324     * @throws IllegalArgumentException if there is no property
325     *  of the specified name
326     * @throws IllegalArgumentException if the specified property
327     *  exists, but is not indexed
328     * @throws IndexOutOfBoundsException if the specified index
329     *  is outside the range of the underlying property
330     */
331    public void set(final String name, final int index, final Object value) {
332
333        final Object prop = values.get(name);
334        if (prop == null) {
335            throw new NullPointerException
336                    ("No indexed value for '" + name + "[" + index + "]'");
337        } else if (prop.getClass().isArray()) {
338            Array.set(prop, index, value);
339        } else if (prop instanceof List) {
340            try {
341                @SuppressWarnings("unchecked")
342                final
343                // This is safe to cast because list properties are always
344                // of type Object
345                List<Object> list = (List<Object>) prop;
346                list.set(index, value);
347            } catch (final ClassCastException e) {
348                throw new ConversionException(e.getMessage());
349            }
350        } else {
351            throw new IllegalArgumentException
352                    ("Non-indexed property for '" + name + "[" + index + "]'");
353        }
354
355    }
356
357
358    /**
359     * Set the value of a mapped property with the specified name.
360     *
361     * @param name Name of the property whose value is to be set
362     * @param key Key of the property to be set
363     * @param value Value to which this property is to be set
364     *
365     * @throws ConversionException if the specified value cannot be
366     *  converted to the type required for this property
367     * @throws IllegalArgumentException if there is no property
368     *  of the specified name
369     * @throws IllegalArgumentException if the specified property
370     *  exists, but is not mapped
371     */
372    public void set(final String name, final String key, final Object value) {
373
374        final Object prop = values.get(name);
375        if (prop == null) {
376            throw new NullPointerException
377                    ("No mapped value for '" + name + "(" + key + ")'");
378        } else if (prop instanceof Map) {
379            @SuppressWarnings("unchecked")
380            final
381            // This is safe to cast because mapped properties are always
382            // maps of types String -> Object
383            Map<String, Object> map = (Map<String, Object>) prop;
384            map.put(key, value);
385        } else {
386            throw new IllegalArgumentException
387                    ("Non-mapped property for '" + name + "(" + key + ")'");
388        }
389
390    }
391
392
393    // ------------------------------------------------------ Protected Methods
394
395
396    /**
397     * Return the property descriptor for the specified property name.
398     *
399     * @param name Name of the property for which to retrieve the descriptor
400     * @return The property descriptor
401     *
402     * @throws IllegalArgumentException if this is not a valid property
403     *  name for our DynaClass
404     */
405    protected DynaProperty getDynaProperty(final String name) {
406
407        final DynaProperty descriptor = getDynaClass().getDynaProperty(name);
408        if (descriptor == null) {
409            throw new IllegalArgumentException
410                    ("Invalid property name '" + name + "'");
411        }
412        return (descriptor);
413
414    }
415
416
417    /**
418     * Is an object of the source class assignable to the destination class?
419     *
420     * @param dest Destination class
421     * @param source Source class
422     * @return <code>true</code> if the source class is assignable to the
423     * destination class, otherwise <code>false</code>
424     */
425    protected boolean isAssignable(final Class<?> dest, final Class<?> source) {
426
427        if (dest.isAssignableFrom(source) ||
428                ((dest == Boolean.TYPE) && (source == Boolean.class)) ||
429                ((dest == Byte.TYPE) && (source == Byte.class)) ||
430                ((dest == Character.TYPE) && (source == Character.class)) ||
431                ((dest == Double.TYPE) && (source == Double.class)) ||
432                ((dest == Float.TYPE) && (source == Float.class)) ||
433                ((dest == Integer.TYPE) && (source == Integer.class)) ||
434                ((dest == Long.TYPE) && (source == Long.class)) ||
435                ((dest == Short.TYPE) && (source == Short.class))) {
436            return (true);
437        } else {
438            return (false);
439        }
440
441    }
442
443
444}