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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 }