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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  
19  package org.apache.commons.beanutils.converters;
20  
21  
22  import java.util.List;
23  import org.apache.commons.beanutils.ConversionException;
24  
25  
26  /***
27   * <p>Standard {@link org.apache.commons.beanutils.Converter} implementation that converts an incoming
28   * String into a primitive array of boolean.  On a conversion failure, returns
29   * a specified default value or throws a {@link ConversionException} depending
30   * on how this instance is constructed.</p>
31   *
32   * <p>By default, the values to be converted are expected to be those
33   * recognised by a default instance of BooleanConverter. A customised
34   * BooleanConverter can be provided in order to recognise alternative values
35   * as true/false. </p>
36   *
37   * @author Craig R. McClanahan
38   * @version $Revision: 556229 $ $Date: 2007-07-14 07:11:19 +0100 (Sat, 14 Jul 2007) $
39   * @since 1.4
40   * @deprecated Replaced by the new {@link ArrayConverter} implementation
41   */
42  
43  public final class BooleanArrayConverter extends AbstractArrayConverter {
44  
45  
46      // ----------------------------------------------------------- Constructors
47  
48  
49      /***
50       * Create a {@link org.apache.commons.beanutils.Converter} that will throw
51       * a {@link ConversionException} if a conversion error occurs.
52       *
53       * <p>Conversion of strings to boolean values will be done via a default
54       * instance of class BooleanConverter.</p>
55       */
56      public BooleanArrayConverter() {
57  
58          super();
59          this.booleanConverter = DEFAULT_CONVERTER;
60  
61      }
62  
63  
64      /***
65       * Create a {@link org.apache.commons.beanutils.Converter} that will return
66       * the specified default value if a conversion error occurs.
67       *
68       * <p>Conversion of strings to boolean values will be done via a default
69       * instance of class BooleanConverter.</p>
70       *
71       * @param defaultValue The default value to be returned
72       */
73      public BooleanArrayConverter(Object defaultValue) {
74  
75          super(defaultValue);
76          this.booleanConverter = DEFAULT_CONVERTER;
77  
78      }
79  
80  
81      /***
82       * Create a {@link org.apache.commons.beanutils.Converter} that will return
83       * the specified default value if a conversion error occurs.
84       *
85       * <p>Conversion of strings to boolean values will be done via the
86       * specified converter.</p>
87       *
88       * @param converter is the converter object that will be used to
89       *  convert each input string-value into a boolean.
90       *
91       * @param defaultValue is the default value to be returned by method
92       * convert if conversion fails; null is a valid default value. See the
93       * documentation for method "convert" for more information.
94       * The value BooleanArrayConverter.NO_DEFAULT may be passed here to
95       * specify that an exception should be thrown on conversion failure.
96       *  
97       */
98      public BooleanArrayConverter(BooleanConverter converter, Object defaultValue) {
99  
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 }