Source code
Description: source: package: org.apache.commons.validator.routines, class: DoubleValidator

    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}