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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    *      https://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  package org.apache.commons.validator.routines;
18  
19  import java.text.Format;
20  import java.text.NumberFormat;
21  import java.util.Locale;
22  
23  /**
24   * <p><strong>Double Validation</strong> and Conversion routines ({@link Double}).</p>
25   *
26   * <p>This validator provides a number of methods for
27   *    validating/converting a {@link String} value to
28   *    a {@code Double} using {@link NumberFormat}
29   *    to parse either:</p>
30   *    <ul>
31   *       <li>using the default format for the default {@link Locale}</li>
32   *       <li>using a specified pattern with the default {@link Locale}</li>
33   *       <li>using the default format for a specified {@link Locale}</li>
34   *       <li>using a specified pattern with a specified {@link Locale}</li>
35   *    </ul>
36   *
37   * <p>Use one of the {@code isValid()} methods to just validate or
38   *    one of the {@code validate()} methods to validate and receive a
39   *    <em>converted</em> {@code Double} value.</p>
40   *
41   * <p>Once a value has been successfully converted the following
42   *    methods can be used to perform minimum, maximum and range checks:</p>
43   *    <ul>
44   *       <li>{@code minValue()} checks whether the value is greater
45   *           than or equal to a specified minimum.</li>
46   *       <li>{@code maxValue()} checks whether the value is less
47   *           than or equal to a specified maximum.</li>
48   *       <li>{@code isInRange()} checks whether the value is within
49   *           a specified range of values.</li>
50   *    </ul>
51   *
52   * <p>So that the same mechanism used for parsing an <em>input</em> value
53   *    for validation can be used to format <em>output</em>, corresponding
54   *    {@code format()} methods are also provided. That is you can
55   *    format either:</p>
56   *    <ul>
57   *       <li>using the default format for the default {@link Locale}</li>
58   *       <li>using a specified pattern with the default {@link Locale}</li>
59   *       <li>using the default format for a specified {@link Locale}</li>
60   *       <li>using a specified pattern with a specified {@link Locale}</li>
61   *    </ul>
62   *
63   * @since 1.3.0
64   */
65  public class DoubleValidator extends AbstractNumberValidator {
66  
67      private static final long serialVersionUID = 5867946581318211330L;
68  
69      private static final DoubleValidator VALIDATOR = new DoubleValidator();
70  
71      /**
72       * Gets the singleton instance of this validator.
73       *
74       * @return A singleton instance of the DoubleValidator.
75       */
76      public static DoubleValidator getInstance() {
77          return VALIDATOR;
78      }
79  
80      /**
81       * Constructs a <em>strict</em> instance.
82       */
83      public DoubleValidator() {
84          this(true, STANDARD_FORMAT);
85      }
86  
87      /**
88       * <p>Construct an instance with the specified strict setting
89       *    and format type.</p>
90       *
91       * <p>The {@code formatType} specified what type of
92       *    {@code NumberFormat} is created - valid types
93       *    are:</p>
94       *    <ul>
95       *       <li>AbstractNumberValidator.STANDARD_FORMAT -to create
96       *           <em>standard</em> number formats (the default).</li>
97       *       <li>AbstractNumberValidator.CURRENCY_FORMAT -to create
98       *           <em>currency</em> number formats.</li>
99       *       <li>AbstractNumberValidator.PERCENT_FORMAT -to create
100      *           <em>percent</em> number formats (the default).</li>
101      *    </ul>
102      *
103      * @param strict {@code true} if strict
104      *        {@code Format} parsing should be used.
105      * @param formatType The {@code NumberFormat} type to
106      *        create for validation, default is STANDARD_FORMAT.
107      */
108     public DoubleValidator(final boolean strict, final int formatType) {
109         super(strict, formatType, true);
110     }
111 
112     /**
113      * Check if the value is within a specified range.
114      *
115      * @param value The {@code Number} value to check.
116      * @param min The minimum value of the range.
117      * @param max The maximum value of the range.
118      * @return {@code true} if the value is within the
119      *         specified range.
120      */
121     public boolean isInRange(final double value, final double min, final double max) {
122         return value >= min && value <= max;
123     }
124 
125     /**
126      * Check if the value is within a specified range.
127      *
128      * @param value The {@code Number} value to check.
129      * @param min The minimum value of the range.
130      * @param max The maximum value of the range.
131      * @return {@code true} if the value is within the
132      *         specified range.
133      */
134     public boolean isInRange(final Double value, final double min, final double max) {
135         return isInRange(value.doubleValue(), min, max);
136     }
137 
138     /**
139      * Check if the value is less than or equal to a maximum.
140      *
141      * @param value The value validation is being performed on.
142      * @param max The maximum value.
143      * @return {@code true} if the value is less than
144      *         or equal to the maximum.
145      */
146     public boolean maxValue(final double value, final double max) {
147         return value <= max;
148     }
149 
150     /**
151      * Check if the value is less than or equal to a maximum.
152      *
153      * @param value The value validation is being performed on.
154      * @param max The maximum value.
155      * @return {@code true} if the value is less than
156      *         or equal to the maximum.
157      */
158     public boolean maxValue(final Double value, final double max) {
159         return maxValue(value.doubleValue(), max);
160     }
161 
162     /**
163      * Check if the value is greater than or equal to a minimum.
164      *
165      * @param value The value validation is being performed on.
166      * @param min The minimum value.
167      * @return {@code true} if the value is greater than
168      *         or equal to the minimum.
169      */
170     public boolean minValue(final double value, final double min) {
171         return value >= min;
172     }
173 
174     /**
175      * Check if the value is greater than or equal to a minimum.
176      *
177      * @param value The value validation is being performed on.
178      * @param min The minimum value.
179      * @return {@code true} if the value is greater than
180      *         or equal to the minimum.
181      */
182     public boolean minValue(final Double value, final double min) {
183         return minValue(value.doubleValue(), min);
184     }
185 
186     /**
187      * Convert the parsed value to a {@code Double}.
188      *
189      * @param value The parsed {@code Number} object created.
190      * @param formatter The Format used to parse the value with.
191      * @return The validated/converted {@code Double} value if valid
192      * or {@code null} if invalid.
193      */
194     @Override
195     protected Object processParsedValue(final Object value, final Format formatter) {
196         if (value instanceof Double) {
197             return value;
198         }
199         return Double.valueOf(((Number) value).doubleValue());
200 
201     }
202 
203     /**
204      * <p>Validate/convert a {@code Double} using the default
205      *    {@link Locale}.
206      *
207      * @param value The value validation is being performed on.
208      * @return The parsed {@code Double} if valid or {@code null}
209      *  if invalid.
210      */
211     public Double validate(final String value) {
212         return (Double) parse(value, (String) null, (Locale) null);
213     }
214 
215     /**
216      * <p>Validate/convert a {@code Double} using the
217      *    specified {@link Locale}.
218      *
219      * @param value The value validation is being performed on.
220      * @param locale The locale to use for the number format, system default if null.
221      * @return The parsed {@code Double} if valid or {@code null} if invalid.
222      */
223     public Double validate(final String value, final Locale locale) {
224         return (Double) parse(value, (String) null, locale);
225     }
226 
227     /**
228      * <p>Validate/convert a {@code Double} using the
229      *    specified <em>pattern</em>.
230      *
231      * @param value The value validation is being performed on.
232      * @param pattern The pattern used to validate the value against.
233      * @return The parsed {@code BigDecimal} if valid or {@code null} if invalid.
234      */
235     public Double validate(final String value, final String pattern) {
236         return (Double) parse(value, pattern, (Locale) null);
237     }
238 
239     /**
240      * <p>Validate/convert a {@code Double} using the
241      *    specified pattern and/ or {@link Locale}.
242      *
243      * @param value The value validation is being performed on.
244      * @param pattern The pattern used to validate the value against, or the
245      *        default for the {@link Locale} if {@code null}.
246      * @param locale The locale to use for the date format, system default if null.
247      * @return The parsed {@code Double} if valid or {@code null} if invalid.
248      */
249     public Double validate(final String value, final String pattern, final Locale locale) {
250         return (Double) parse(value, pattern, locale);
251     }
252 }