Source code

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 *      https://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 */
017package org.apache.commons.validator.routines;
018
019import java.text.Format;
020import java.text.NumberFormat;
021import java.util.Locale;
022
023/**
024 * <strong>Double Validation</strong> and Conversion routines ({@link Double}).
025 *
026 * <p>This validator provides a number of methods for
027 *    validating/converting a {@link String} value to
028 *    a {@code Double} using {@link NumberFormat}
029 *    to parse either:</p>
030 *    <ul>
031 *       <li>using the default format for the default {@link Locale}</li>
032 *       <li>using a specified pattern with the default {@link Locale}</li>
033 *       <li>using the default format for a specified {@link Locale}</li>
034 *       <li>using a specified pattern with a specified {@link Locale}</li>
035 *    </ul>
036 *
037 * <p>Use one of the {@code isValid()} methods to just validate or
038 *    one of the {@code validate()} methods to validate and receive a
039 *    <em>converted</em> {@code Double} value.</p>
040 *
041 * <p>Once a value has been successfully converted the following
042 *    methods can be used to perform minimum, maximum and range checks:</p>
043 *    <ul>
044 *       <li>{@code minValue()} checks whether the value is greater
045 *           than or equal to a specified minimum.</li>
046 *       <li>{@code maxValue()} checks whether the value is less
047 *           than or equal to a specified maximum.</li>
048 *       <li>{@code isInRange()} checks whether the value is within
049 *           a specified range of values.</li>
050 *    </ul>
051 *
052 * <p>So that the same mechanism used for parsing an <em>input</em> value
053 *    for validation can be used to format <em>output</em>, corresponding
054 *    {@code format()} methods are also provided. That is you can
055 *    format either:</p>
056 *    <ul>
057 *       <li>using the default format for the default {@link Locale}</li>
058 *       <li>using a specified pattern with the default {@link Locale}</li>
059 *       <li>using the default format for a specified {@link Locale}</li>
060 *       <li>using a specified pattern with a specified {@link Locale}</li>
061 *    </ul>
062 *
063 * @since 1.3.0
064 */
065public class DoubleValidator extends AbstractNumberValidator {
066
067    private static final long serialVersionUID = 5867946581318211330L;
068
069    private static final DoubleValidator VALIDATOR = new DoubleValidator();
070
071    /**
072     * Gets the singleton instance of this validator.
073     *
074     * @return A singleton instance of the DoubleValidator.
075     */
076    public static DoubleValidator getInstance() {
077        return VALIDATOR;
078    }
079
080    /**
081     * Constructs a <em>strict</em> instance.
082     */
083    public DoubleValidator() {
084        this(true, STANDARD_FORMAT);
085    }
086
087    /**
088     * Construct an instance with the specified strict setting
089     *    and format type.
090     *
091     * <p>The {@code formatType} specified what type of
092     *    {@code NumberFormat} is created - valid types
093     *    are:</p>
094     *    <ul>
095     *       <li>AbstractNumberValidator.STANDARD_FORMAT -to create
096     *           <em>standard</em> number formats (the default).</li>
097     *       <li>AbstractNumberValidator.CURRENCY_FORMAT -to create
098     *           <em>currency</em> number formats.</li>
099     *       <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     * Tests if the value is less than or equal to a maximum, comparing the exact values.
164     *
165     * <p>
166     * This overrides the {@link Number} overload inherited from the superclass, which narrows the bound to a {@code double} before comparing and so loses
167     * precision for a {@code BigDecimal} or {@code BigInteger} bound that carries more significant digits than a {@code double} can hold. A non-finite
168     * {@link Double} or {@link Float} operand keeps the {@code doubleValue()} comparison so the documented infinity behavior is unchanged.
169     * </p>
170     *
171     * @param value The value validation is being performed on.
172     * @param max   The maximum value.
173     * @return {@code true} if the value is less than or equal to the maximum.
174     */
175    @Override
176    public boolean maxValue(final Number value, final Number max) {
177        return isFinite(value) && isFinite(max) ? compareTo(value, max) <= 0 : value.doubleValue() <= max.doubleValue();
178    }
179
180    /**
181     * Check if the value is greater than or equal to a minimum.
182     *
183     * @param value The value validation is being performed on.
184     * @param min The minimum value.
185     * @return {@code true} if the value is greater than
186     *         or equal to the minimum.
187     */
188    public boolean minValue(final double value, final double min) {
189        return value >= min;
190    }
191
192    /**
193     * Check if the value is greater than or equal to a minimum.
194     *
195     * @param value The value validation is being performed on.
196     * @param min The minimum value.
197     * @return {@code true} if the value is greater than
198     *         or equal to the minimum.
199     */
200    public boolean minValue(final Double value, final double min) {
201        return minValue(value.doubleValue(), min);
202    }
203
204    /**
205     * Tests if the value is greater than or equal to a minimum, comparing the exact values.
206     *
207     * <p>
208     * This overrides the {@link Number} overload inherited from the superclass, which narrows the bound to a {@code double} before comparing and so loses
209     * precision for a {@code BigDecimal} or {@code BigInteger} bound that carries more significant digits than a {@code double} can hold. A non-finite
210     * {@link Double} or {@link Float} operand keeps the {@code doubleValue()} comparison so the documented infinity behavior is unchanged.
211     * </p>
212     *
213     * @param value The value validation is being performed on.
214     * @param min   The minimum value.
215     * @return {@code true} if the value is greater than or equal to the minimum.
216     */
217    @Override
218    public boolean minValue(final Number value, final Number min) {
219        return isFinite(value) && isFinite(min) ? compareTo(value, min) >= 0 : value.doubleValue() >= min.doubleValue();
220    }
221
222    /**
223     * Convert the parsed value to a {@code Double}.
224     *
225     * @param value The parsed {@code Number} object created.
226     * @param formatter The Format used to parse the value with.
227     * @return The validated/converted {@code Double} value if valid
228     * or {@code null} if invalid.
229     */
230    @Override
231    protected Object processParsedValue(final Object value, final Format formatter) {
232        if (value instanceof Double) {
233            return value;
234        }
235        return Double.valueOf(((Number) value).doubleValue());
236    }
237
238    /**
239     * Validate/convert a {@code Double} using the default
240     *    {@link Locale}.
241     *
242     * @param value The value validation is being performed on.
243     * @return The parsed {@code Double} if valid or {@code null}
244     *  if invalid.
245     */
246    public Double validate(final String value) {
247        return (Double) parse(value, (String) null, (Locale) null);
248    }
249
250    /**
251     * Validate/convert a {@code Double} using the
252     *    specified {@link Locale}.
253     *
254     * @param value The value validation is being performed on.
255     * @param locale The locale to use for the number format, system default if null.
256     * @return The parsed {@code Double} if valid or {@code null} if invalid.
257     */
258    public Double validate(final String value, final Locale locale) {
259        return (Double) parse(value, (String) null, locale);
260    }
261
262    /**
263     * Validate/convert a {@code Double} using the
264     *    specified <em>pattern</em>.
265     *
266     * @param value The value validation is being performed on.
267     * @param pattern The pattern used to validate the value against.
268     * @return The parsed {@code BigDecimal} if valid or {@code null} if invalid.
269     */
270    public Double validate(final String value, final String pattern) {
271        return (Double) parse(value, pattern, (Locale) null);
272    }
273
274    /**
275     * Validate/convert a {@code Double} using the
276     *    specified pattern and/ or {@link Locale}.
277     *
278     * @param value The value validation is being performed on.
279     * @param pattern The pattern used to validate the value against, or the
280     *        default for the {@link Locale} if {@code null}.
281     * @param locale The locale to use for the date format, system default if null.
282     * @return The parsed {@code Double} if valid or {@code null} if invalid.
283     */
284    public Double validate(final String value, final String pattern, final Locale locale) {
285        return (Double) parse(value, pattern, locale);
286    }
287}