    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
    019    package org.apache.commons.beanutils;
    020
    021    import java.io.Serializable;
    022    import 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: 555824 $ $Date: 2007-07-13 01:27:15 +0100 (Fri, 13 Jul 2007) $
    046     */
    047
    048    public 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    }