    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
    018package org.apache.commons.beanutils;
    019
    020import org.apache.commons.collections.Closure;
    021import org.apache.commons.logging.Log;
    022import org.apache.commons.logging.LogFactory;
    023
    024import java.lang.reflect.InvocationTargetException;
    025
    026
    027/**
    028 * <p><code>Closure</code> that sets a property.</p>
    029 * <p>
    030 * An implementation of <code>org.apache.commons.collections.Closure</code> that updates
    031 * a specified property on the object provided with a specified value.
    032 * The <code>BeanPropertyValueChangeClosure</code> constructor takes two parameters which determine
    033 * what property will be updated and with what value.
    034 * <dl>
    035 *    <dt>
    036 *       <b><code>
    037 *           <pre>public BeanPropertyValueChangeClosure( String propertyName, Object propertyValue )</pre>
    038 *       </code></b>
    039 *    </dt>
    040 *    <dd>
    041 *       Will create a <code>Closure</code> that will update an object by setting the property
    042 *       specified by <code>propertyName</code> to the value specified by <code>propertyValue</code>.
    043 *    </dd>
    044 * </dl>
    045 *
    046 * <p/>
    047 * <strong>Note:</strong> Property names can be a simple, nested, indexed, or mapped property as defined by
    048 * <code>org.apache.commons.beanutils.PropertyUtils</code>.  If any object in the property path
    049 * specified by <code>propertyName</code> is <code>null</code> then the outcome is based on the
    050 * value of the <code>ignoreNull</code> attribute.
    051 *
    052 * <p/>
    053 * A typical usage might look like:
    054 * <code><pre>
    055 * // create the closure
    056 * BeanPropertyValueChangeClosure closure =
    057 *    new BeanPropertyValueChangeClosure( "activeEmployee", Boolean.TRUE );
    058 *
    059 * // update the Collection
    060 * CollectionUtils.forAllDo( peopleCollection, closure );
    061 * </pre></code>
    062 * <p/>
    063 *
    064 * This would take a <code>Collection</code> of person objects and update the
    065 * <code>activeEmployee</code> property of each object in the <code>Collection</code> to
    066 * <code>true</code>. Assuming...
    067 * <ul>
    068 *    <li>
    069 *       The top level object in the <code>peopleCollection</code> is an object which represents a
    070 *       person.
    071 *    </li>
    072 *    <li>
    073 *       The person object has a <code>setActiveEmployee( boolean )</code> method which updates
    074 *       the value for the object's <code>activeEmployee</code> property.
    075 *    </li>
    076 * </ul>
    077 *
    078 * @version $Id$
    079 * @see org.apache.commons.beanutils.PropertyUtils
    080 * @see org.apache.commons.collections.Closure
    081 */
    082public class BeanPropertyValueChangeClosure implements Closure {
    083
    084    /** For logging. */
    085    private final Log log = LogFactory.getLog(this.getClass());
    086
    087    /**
    088     * The name of the property which will be updated when this <code>Closure</code> executes.
    089     */
    090    private String propertyName;
    091
    092    /**
    093     * The value that the property specified by <code>propertyName</code>
    094     * will be updated to when this <code>Closure</code> executes.
    095     */
    096    private Object propertyValue;
    097
    098    /**
    099     * Determines whether <code>null</code> objects in the property path will genenerate an
    100     * <code>IllegalArgumentException</code> or not. If set to <code>true</code> then if any objects
    101     * in the property path leading up to the target property evaluate to <code>null</code> then the
    102     * <code>IllegalArgumentException</code> throw by <code>PropertyUtils</code> will be logged but
    103     * not rethrown.  If set to <code>false</code> then if any objects in the property path leading
    104     * up to the target property evaluate to <code>null</code> then the
    105     * <code>IllegalArgumentException</code> throw by <code>PropertyUtils</code> will be logged and
    106     * rethrown.
    107     */
    108    private boolean ignoreNull;
    109
    110    /**
    111     * Constructor which takes the name of the property to be changed, the new value to set
    112     * the property to, and assumes <code>ignoreNull</code> to be <code>false</code>.
    113     *
    114     * @param propertyName The name of the property that will be updated with the value specified by
    115     * <code>propertyValue</code>.
    116     * @param propertyValue The value that <code>propertyName</code> will be set to on the target
    117     * object.
    118     * @throws IllegalArgumentException If the propertyName provided is null or empty.
    119     */
    120    public BeanPropertyValueChangeClosure(final String propertyName, final Object propertyValue) {
    121        this(propertyName, propertyValue, false);
    122    }
    123
    124    /**
    125     * Constructor which takes the name of the property to be changed, the new value to set
    126     * the property to and a boolean which determines whether <code>null</code> objects in the
    127     * property path will genenerate an <code>IllegalArgumentException</code> or not.
    128     *
    129     * @param propertyName The name of the property that will be updated with the value specified by
    130     * <code>propertyValue</code>.
    131     * @param propertyValue The value that <code>propertyName</code> will be set to on the target
    132     * object.
    133     * @param ignoreNull Determines whether <code>null</code> objects in the property path will
    134     * genenerate an <code>IllegalArgumentException</code> or not.
    135     * @throws IllegalArgumentException If the propertyName provided is null or empty.
    136     */
    137    public BeanPropertyValueChangeClosure(final String propertyName, final Object propertyValue, final boolean ignoreNull) {
    138        super();
    139
    140        if ((propertyName != null) && (propertyName.length() > 0)) {
    141            this.propertyName = propertyName;
    142            this.propertyValue = propertyValue;
    143            this.ignoreNull = ignoreNull;
    144        } else {
    145            throw new IllegalArgumentException("propertyName cannot be null or empty");
    146        }
    147    }
    148
    149    /**
    150     * Updates the target object provided using the property update criteria provided when this
    151     * <code>BeanPropertyValueChangeClosure</code> was constructed.  If any object in the property
    152     * path leading up to the target property is <code>null</code> then the outcome will be based on
    153     * the value of the <code>ignoreNull</code> attribute. By default, <code>ignoreNull</code> is
    154     * <code>false</code> and would result in an <code>IllegalArgumentException</code> if an object
    155     * in the property path leading up to the target property is <code>null</code>.
    156     *
    157     * @param object The object to be updated.
    158     * @throws IllegalArgumentException If an IllegalAccessException, InvocationTargetException, or
    159     * NoSuchMethodException is thrown when trying to access the property specified on the object
    160     * provided. Or if an object in the property path provided is <code>null</code> and
    161     * <code>ignoreNull</code> is set to <code>false</code>.
    162     */
    163    public void execute(final Object object) {
    164
    165        try {
    166            PropertyUtils.setProperty(object, propertyName, propertyValue);
    167        } catch (final IllegalArgumentException e) {
    168            final String errorMsg = "Unable to execute Closure. Null value encountered in property path...";
    169
    170            if (ignoreNull) {
    171                log.warn("WARNING: " + errorMsg + e);
    172            } else {
    173                final IllegalArgumentException iae = new IllegalArgumentException(errorMsg);
    174                if (!BeanUtils.initCause(iae, e)) {
    175                    log.error(errorMsg, e);
    176                }
    177                throw iae;
    178            }
    179        } catch (final IllegalAccessException e) {
    180            final String errorMsg = "Unable to access the property provided.";
    181            final IllegalArgumentException iae = new IllegalArgumentException(errorMsg);
    182            if (!BeanUtils.initCause(iae, e)) {
    183                log.error(errorMsg, e);
    184            }
    185            throw iae;
    186        } catch (final InvocationTargetException e) {
    187            final String errorMsg = "Exception occurred in property's getter";
    188            final IllegalArgumentException iae = new IllegalArgumentException(errorMsg);
    189            if (!BeanUtils.initCause(iae, e)) {
    190                log.error(errorMsg, e);
    191            }
    192            throw iae;
    193        } catch (final NoSuchMethodException e) {
    194            final String errorMsg = "Property not found";
    195            final IllegalArgumentException iae = new IllegalArgumentException(errorMsg);
    196            if (!BeanUtils.initCause(iae, e)) {
    197                log.error(errorMsg, e);
    198            }
    199            throw iae;
    200        }
    201    }
    202
    203    /**
    204     * Returns the name of the property which will be updated when this <code>Closure</code> executes.
    205     *
    206     * @return The name of the property which will be updated when this <code>Closure</code> executes.
    207     */
    208    public String getPropertyName() {
    209        return propertyName;
    210    }
    211
    212    /**
    213     * Returns the value that the property specified by <code>propertyName</code>
    214     * will be updated to when this <code>Closure</code> executes.
    215     *
    216     * @return The value that the property specified by <code>propertyName</code>
    217     * will be updated to when this <code>Closure</code> executes.
    218     */
    219    public Object getPropertyValue() {
    220        return propertyValue;
    221    }
    222
    223    /**
    224     * Returns the flag that determines whether <code>null</code> objects in the property path will
    225     * genenerate an <code>IllegalArgumentException</code> or not. If set to <code>true</code> then
    226     * if any objects in the property path leading up to the target property evaluate to
    227     * <code>null</code> then the <code>IllegalArgumentException</code> throw by
    228     * <code>PropertyUtils</code> will be logged but not rethrown.  If set to <code>false</code> then
    229     * if any objects in the property path leading up to the target property evaluate to
    230     * <code>null</code> then the <code>IllegalArgumentException</code> throw by
    231     * <code>PropertyUtils</code> will be logged and rethrown.
    232     *
    233     * @return The flag that determines whether <code>null</code> objects in the property path will
    234     * genenerate an <code>IllegalArgumentException</code> or not.
    235     */
    236    public boolean isIgnoreNull() {
    237        return ignoreNull;
    238    }
    239}