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    1   /*
    2    * $Id: BigDecimalValidator.java 386637 2006-03-17 13:22:26Z niallp $
    3    * $Revision: 386637 $
    4    * $Date: 2006-03-17 13:22:26 +0000 (Fri, 17 Mar 2006) $
    5    *
    6    * ====================================================================
    7    * Copyright 2006 The Apache Software Foundation
    8    *
    9    * Licensed under the Apache License, Version 2.0 (the "License");
    10   * you may not use this file except in compliance with the License.
    11   * You may obtain a copy of the License at
    12   *
    13   *     http://www.apache.org/licenses/LICENSE-2.0
    14   *
    15   * Unless required by applicable law or agreed to in writing, software
    16   * distributed under the License is distributed on an "AS IS" BASIS,
    17   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    18   * See the License for the specific language governing permissions and
    19   * limitations under the License.
    20   */
    21  package org.apache.commons.validator.routines;
    22
    23  import java.math.BigDecimal;
    24  import java.text.Format;
    25  import java.text.NumberFormat;
    26  import java.util.Locale;
    27
    28  /***
    29   * <p><b>BigDecimal Validation</b> and Conversion routines (<code>java.math.BigDecimal</code>).</p>
    30   *
    31   * <p>This validator provides a number of methods for
    32   *    validating/converting a <code>String</code> value to
    33   *    a <code>BigDecimal</code> using <code>java.text.NumberFormat</code>
    34   *    to parse either:</p>
    35   *    <ul>
    36   *       <li>using the default format for the default <code>Locale</code></li>
    37   *       <li>using a specified pattern with the default <code>Locale</code></li>
    38   *       <li>using the default format for a specified <code>Locale</code></li>
    39   *       <li>using a specified pattern with a specified <code>Locale</code></li>
    40   *    </ul>
    41   *
    42   * <p>Use one of the <code>isValid()</code> methods to just validate or
    43   *    one of the <code>validate()</code> methods to validate and receive a
    44   *    <i>converted</i> <code>BigDecimal</code> value.</p>
    45   *
    46   * <p>Fraction/decimal values are automatically trimmed to the appropriate length.</p>
    47   *
    48   * <p>Once a value has been sucessfully converted the following
    49   *    methods can be used to perform minimum, maximum and range checks:</p>
    50   *    <ul>
    51   *       <li><code>minValue()</code> checks whether the value is greater
    52   *           than or equal to a specified minimum.</li>
    53   *       <li><code>maxValue()</code> checks whether the value is less
    54   *           than or equal to a specified maximum.</li>
    55   *       <li><code>isInRange()</code> checks whether the value is within
    56   *           a specified range of values.</li>
    57   *    </ul>
    58   *
    59   * <p>So that the same mechanism used for parsing an <i>input</i> value
    60   *    for validation can be used to format <i>output</i>, corresponding
    61   *    <code>format()</code> methods are also provided. That is you can
    62   *    format either:</p>
    63   *    <ul>
    64   *       <li>using the default format for the default <code>Locale</code></li>
    65   *       <li>using a specified pattern with the default <code>Locale</code></li>
    66   *       <li>using the default format for a specified <code>Locale</code></li>
    67   *       <li>using a specified pattern with a specified <code>Locale</code></li>
    68   *    </ul>
    69   *
    70   * @version $Revision: 386637 $ $Date: 2006-03-17 13:22:26 +0000 (Fri, 17 Mar 2006) $
    71   * @since Validator 1.3.0
    72   */
    73  public class BigDecimalValidator extends AbstractNumberValidator {
    74
    75      private static final BigDecimalValidator VALIDATOR = new BigDecimalValidator();
    76
    77      /***
    78       * Return a singleton instance of this validator.
    79       * @return A singleton instance of the BigDecimalValidator.
    80       */
    81      public static BigDecimalValidator getInstance() {
    82          return VALIDATOR;
    83      }
    84
    85      /***
    86       * Construct a <i>strict</i> instance.
    87       */
    88      public BigDecimalValidator() {
    89          this(true);
    90      }
    91
    92      /***
    93       * <p>Construct an instance with the specified strict setting.</p>
    94       *
    95       * @param strict <code>true</code> if strict
    96       *        <code>Format</code> parsing should be used.
    97       */
    98      public BigDecimalValidator(boolean strict) {
    99          this(strict, STANDARD_FORMAT, true);
    100     }
    101
    102     /***
    103      * <p>Construct an instance with the specified strict setting
    104      *    and format type.</p>
    105      *
    106      * <p>The <code>formatType</code> specified what type of
    107      *    <code>NumberFormat</code> is created - valid types
    108      *    are:</p>
    109      *    <ul>
    110      *       <li>AbstractNumberValidator.STANDARD_FORMAT -to create
    111      *           <i>standard</i> number formats (the default).</li>
    112      *       <li>AbstractNumberValidator.CURRENCY_FORMAT -to create
    113      *           <i>currency</i> number formats.</li>
    114      *       <li>AbstractNumberValidator.PERCENT_FORMAT -to create
    115      *           <i>percent</i> number formats (the default).</li>
    116      *    </ul>
    117      *
    118      * @param strict <code>true</code> if strict
    119      *        <code>Format</code> parsing should be used.
    120      * @param formatType The <code>NumberFormat</code> type to
    121      *        create for validation, default is STANDARD_FORMAT.
    122      * @param allowFractions <code>true</code> if fractions are
    123      *        allowed or <code>false</code> if integers only.
    124      */
    125     protected BigDecimalValidator(boolean strict, int formatType,
    126             boolean allowFractions) {
    127         super(strict, formatType, allowFractions);
    128     }
    129
    130     /***
    131      * <p>Validate/convert a <code>BigDecimal</code> using the default
    132      *    <code>Locale</code>.
    133      *
    134      * @param value The value validation is being performed on.
    135      * @return The parsed <code>BigDecimal</code> if valid or <code>null</code>
    136      *  if invalid.
    137      */
    138     public BigDecimal validate(String value) {
    139         return (BigDecimal)parse(value, (String)null, (Locale)null);
    140     }
    141
    142     /***
    143      * <p>Validate/convert a <code>BigDecimal</code> using the
    144      *    specified <i>pattern</i>.
    145      *
    146      * @param value The value validation is being performed on.
    147      * @param pattern The pattern used to validate the value against, or the
    148      *        default for the <code>Locale</code> if <code>null</code>.
    149      * @return The parsed <code>BigDecimal</code> if valid or <code>null</code> if invalid.
    150      */
    151     public BigDecimal validate(String value, String pattern) {
    152         return (BigDecimal)parse(value, pattern, (Locale)null);
    153     }
    154
    155     /***
    156      * <p>Validate/convert a <code>BigDecimal</code> using the
    157      *    specified <code>Locale</code>.
    158      *
    159      * @param value The value validation is being performed on.
    160      * @param locale The locale to use for the number format, system default if null.
    161      * @return The parsed <code>BigDecimal</code> if valid or <code>null</code> if invalid.
    162      */
    163     public BigDecimal validate(String value, Locale locale) {
    164         return (BigDecimal)parse(value, (String)null, locale);
    165     }
    166
    167     /***
    168      * <p>Validate/convert a <code>BigDecimal</code> using the
    169      *    specified pattern and/ or <code>Locale</code>.
    170      *
    171      * @param value The value validation is being performed on.
    172      * @param pattern The pattern used to validate the value against, or the
    173      *        default for the <code>Locale</code> if <code>null</code>.
    174      * @param locale The locale to use for the date format, system default if null.
    175      * @return The parsed <code>BigDecimal</code> if valid or <code>null</code> if invalid.
    176      */
    177     public BigDecimal validate(String value, String pattern, Locale locale) {
    178         return (BigDecimal)parse(value, pattern, locale);
    179     }
    180
    181     /***
    182      * Check if the value is within a specified range.
    183      *
    184      * @param value The <code>Number</code> value to check.
    185      * @param min The minimum value of the range.
    186      * @param max The maximum value of the range.
    187      * @return <code>true</code> if the value is within the
    188      *         specified range.
    189      */
    190     public boolean isInRange(BigDecimal value, double min, double max) {
    191         return (value.doubleValue() >= min && value.doubleValue() <= max);
    192     }
    193
    194     /***
    195      * Check if the value is greater than or equal to a minimum.
    196      *
    197      * @param value The value validation is being performed on.
    198      * @param min The minimum value.
    199      * @return <code>true</code> if the value is greater than
    200      *         or equal to the minimum.
    201      */
    202     public boolean minValue(BigDecimal value, double min) {
    203         return (value.doubleValue() >= min);
    204     }
    205
    206     /***
    207      * Check if the value is less than or equal to a maximum.
    208      *
    209      * @param value The value validation is being performed on.
    210      * @param max The maximum value.
    211      * @return <code>true</code> if the value is less than
    212      *         or equal to the maximum.
    213      */
    214     public boolean maxValue(BigDecimal value, double max) {
    215         return (value.doubleValue() <= max);
    216     }
    217
    218     /***
    219      * Convert the parsed value to a <code>BigDecimal</code>.
    220      *
    221      * @param value The parsed <code>Number</code> object created.
    222      * @param formatter The Format used to parse the value with.
    223      * @return The parsed <code>Number</code> converted to a
    224      *         <code>BigDecimal</code>.
    225      */
    226     protected Object processParsedValue(Object value, Format formatter) {
    227         BigDecimal decimal = null;
    228         if (value instanceof Long) {
    229             decimal = BigDecimal.valueOf(((Long)value).longValue());
    230         } else {
    231             decimal = new BigDecimal(value.toString());
    232         }
    233
    234         int scale = determineScale((NumberFormat)formatter);
    235         if (scale >= 0) {
    236             decimal = decimal.setScale(scale, BigDecimal.ROUND_DOWN);
    237         }
    238
    239         return decimal;
    240     }
    241 }