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.converters;
020    
021    
022    import java.util.List;
023    import org.apache.commons.beanutils.ConversionException;
024    
025    
026    /**
027     * <p>Standard {@link org.apache.commons.beanutils.Converter} implementation that converts an incoming
028     * String into a primitive array of boolean.  On a conversion failure, returns
029     * a specified default value or throws a {@link ConversionException} depending
030     * on how this instance is constructed.</p>
031     *
032     * <p>By default, the values to be converted are expected to be those
033     * recognised by a default instance of BooleanConverter. A customised
034     * BooleanConverter can be provided in order to recognise alternative values
035     * as true/false. </p>
036     *
037     * @author Craig R. McClanahan
038     * @version $Revision: 556229 $ $Date: 2007-07-14 07:11:19 +0100 (Sat, 14 Jul 2007) $
039     * @since 1.4
040     * @deprecated Replaced by the new {@link ArrayConverter} implementation
041     */
042    
043    public final class BooleanArrayConverter extends AbstractArrayConverter {
044    
045    
046        // ----------------------------------------------------------- Constructors
047    
048    
049        /**
050         * Create a {@link org.apache.commons.beanutils.Converter} that will throw
051         * a {@link ConversionException} if a conversion error occurs.
052         *
053         * <p>Conversion of strings to boolean values will be done via a default
054         * instance of class BooleanConverter.</p>
055         */
056        public BooleanArrayConverter() {
057    
058            super();
059            this.booleanConverter = DEFAULT_CONVERTER;
060    
061        }
062    
063    
064        /**
065         * Create a {@link org.apache.commons.beanutils.Converter} that will return
066         * the specified default value if a conversion error occurs.
067         *
068         * <p>Conversion of strings to boolean values will be done via a default
069         * instance of class BooleanConverter.</p>
070         *
071         * @param defaultValue The default value to be returned
072         */
073        public BooleanArrayConverter(Object defaultValue) {
074    
075            super(defaultValue);
076            this.booleanConverter = DEFAULT_CONVERTER;
077    
078        }
079    
080    
081        /**
082         * Create a {@link org.apache.commons.beanutils.Converter} that will return
083         * the specified default value if a conversion error occurs.
084         *
085         * <p>Conversion of strings to boolean values will be done via the
086         * specified converter.</p>
087         *
088         * @param converter is the converter object that will be used to
089         *  convert each input string-value into a boolean.
090         *
091         * @param defaultValue is the default value to be returned by method
092         * convert if conversion fails; null is a valid default value. See the
093         * documentation for method "convert" for more information.
094         * The value BooleanArrayConverter.NO_DEFAULT may be passed here to
095         * specify that an exception should be thrown on conversion failure.
096         *  
097         */
098        public BooleanArrayConverter(BooleanConverter converter, Object defaultValue) {
099    
100            super(defaultValue);
101            this.booleanConverter = converter;
102    
103        }
104    
105        // ------------------------------------------------------- Static Variables
106    
107        /**
108         * Type which this class converts its input to. This value can be
109         * used as a parameter to the ConvertUtils.register method.
110         */
111        public static final Class MODEL = new boolean[0].getClass();
112    
113        /**
114         * The converter that all instances of this class will use to
115         * do individual string->boolean conversions, unless overridden
116         * in the constructor.
117         */
118        private static final BooleanConverter DEFAULT_CONVERTER
119            = new BooleanConverter();
120    
121        // ---------------------------------------------------- Instance Variables
122    
123        /**
124         * This object is used to perform the conversion of individual strings
125         * into Boolean/boolean values.
126         */
127        protected final BooleanConverter booleanConverter;
128    
129        // --------------------------------------------------------- Public Methods
130    
131    
132        /**
133         * Convert the specified input object into an output object of type
134         * array-of-boolean.
135         * 
136         * <p>If the input value is null, then the default value specified in the
137         * constructor is returned. If no such value was provided, then a
138         * ConversionException is thrown instead.</p>
139         *
140         * <p>If the input value is of type String[] then the returned array shall
141         * be of the same size as this array, with a true or false value in each
142         * array element depending on the result of applying method
143         * BooleanConverter.convert to each string.</p>
144         *
145         * <p>For all other types of value, the object's toString method is
146         * expected to return a string containing a comma-separated list of
147         * values, eg "true, false, true". See the documentation for
148         * {@link AbstractArrayConverter#parseElements} for more information on
149         * the exact formats supported.</p>
150         *
151         * <p>If the result of value.toString() cannot be split into separate
152         * words, then the default value is also returned (or an exception thrown).
153         * </p>
154         *
155         * <p>If any of the elements in the value array (or the elements resulting
156         * from splitting up value.toString) are not recognised by the
157         * BooleanConverter associated with this object, then what happens depends
158         * on whether that BooleanConverter has a default value or not: if it does, 
159         * then that unrecognised element is converted into the BooleanConverter's
160         * default value. If the BooleanConverter does <i>not</i> have a default
161         * value, then the default value for this object is returned as the
162         * <i>complete</i> conversion result (not just for the element), or an 
163         * exception is thrown if this object has no default value defined.</p>
164         *
165         * @param type is the type to which this value should be converted. In the
166         *  case of this BooleanArrayConverter class, this value is ignored.
167         *
168         * @param value is the input value to be converted.
169         *
170         * @return an object of type boolean[], or the default value if there was
171         *  any sort of error during conversion and the constructor
172         *  was provided with a default value.
173         *
174         * @exception ConversionException if conversion cannot be performed
175         *  successfully and the constructor was not provided with a default
176         *  value to return on conversion failure.
177         *
178         * @exception NullPointerException if value is an array, and any of the
179         * array elements are null.
180         */
181        public Object convert(Class type, Object value) {
182    
183            // Deal with a null value
184            if (value == null) {
185                if (useDefault) {
186                    return (defaultValue);
187                } else {
188                    throw new ConversionException("No value specified");
189                }
190            }
191    
192            // Deal with the no-conversion-needed case
193            if (MODEL == value.getClass()) {
194                return (value);
195            }
196    
197            // Deal with input value as a String array
198            //
199            // TODO: use if (value.getClass().isArray() instead...
200            //  this requires casting to Object[], then using values[i].toString()
201            if (strings.getClass() == value.getClass()) {
202                try {
203                    String[] values = (String[]) value;
204                    boolean[] results = new boolean[values.length];
205                    for (int i = 0; i < values.length; i++) {
206                        String stringValue = values[i];
207                        Object result = booleanConverter.convert(Boolean.class, stringValue);
208                        results[i] = ((Boolean) result).booleanValue();
209                    }
210                    return (results);
211                } catch (Exception e) {
212                    if (useDefault) {
213                        return (defaultValue);
214                    } else {
215                        throw new ConversionException(value.toString(), e);
216                    }
217                }
218            }
219    
220            // We only get here if the input value is not of type String[].
221            // In this case, we assume value.toString() returns a comma-separated
222            // sequence of values; see method AbstractArrayConverter.parseElements
223            // for more information.
224            try {
225                List list = parseElements(value.toString());
226                boolean[] results = new boolean[list.size()];
227                for (int i = 0; i < results.length; i++) {
228                    String stringValue = (String) list.get(i);
229                    Object result = booleanConverter.convert(Boolean.class, stringValue);
230                    results[i] = ((Boolean) result).booleanValue();
231                }
232                return (results);
233            } catch (Exception e) {
234                if (useDefault) {
235                    return (defaultValue);
236                } else {
237                    throw new ConversionException(value.toString(), e);
238                }
239            }
240    
241        }
242    
243    
244    }