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 *      http://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.DecimalFormatSymbols;
020import java.text.Format;
021import java.text.NumberFormat;
022import java.text.DecimalFormat;
023import java.util.Locale;
024
025/**
026 * <p>Abstract class for Number Validation.</p>
027 *
028 * <p>This is a <i>base</i> class for building Number
029 *    Validators using format parsing.</p>
030 *
031 * @version $Revision: 1227719 $ $Date: 2012-01-05 18:45:51 +0100 (Do, 05 Jan 2012) $
032 * @since Validator 1.3.0
033 */
034public abstract class AbstractNumberValidator extends AbstractFormatValidator {
035
036    private static final long serialVersionUID = -3088817875906765463L;
037
038    /** Standard <code>NumberFormat</code> type */
039    public static final int STANDARD_FORMAT = 0;
040
041    /** Currency <code>NumberFormat</code> type */
042    public static final int CURRENCY_FORMAT = 1;
043
044    /** Percent <code>NumberFormat</code> type */
045    public static final int PERCENT_FORMAT  = 2;
046
047    private final boolean allowFractions;
048    private final int     formatType;
049
050    /**
051     * Construct an instance with specified <i>strict</i>
052     * and <i>decimal</i> parameters.
053     *
054     * @param strict <code>true</code> if strict
055     *        <code>Format</code> parsing should be used.
056     * @param formatType The <code>NumberFormat</code> type to
057     *        create for validation, default is STANDARD_FORMAT.
058     * @param allowFractions <code>true</code> if fractions are
059     *        allowed or <code>false</code> if integers only.
060     */
061    public AbstractNumberValidator(boolean strict, int formatType, boolean allowFractions) {
062        super(strict);
063        this.allowFractions = allowFractions;
064        this.formatType = formatType;
065    }
066
067    /**
068     * <p>Indicates whether the number being validated is
069     *    a decimal or integer.</p>
070     *
071     * @return <code>true</code> if decimals are allowed
072     *       or <code>false</code> if the number is an integer.
073     */
074    public boolean isAllowFractions() {
075        return allowFractions;
076    }
077
078    /**
079     * <p>Indicates the type of <code>NumberFormat</code> created
080     *    by this validator instance.</p>
081     *
082     * @return the format type created.
083     */
084    public int getFormatType() {
085        return formatType;
086    }
087
088    /**
089     * <p>Validate using the specified <code>Locale</code>.</p>
090     *
091     * @param value The value validation is being performed on.
092     * @param pattern The pattern used to validate the value against, or the
093     *        default for the <code>Locale</code> if <code>null</code>.
094     * @param locale The locale to use for the date format, system default if null.
095     * @return <code>true</code> if the value is valid.
096     */
097    public boolean isValid(String value, String pattern, Locale locale) {
098        Object parsedValue = parse(value, pattern, locale);
099        return (parsedValue == null ? false : true);
100    }
101
102    /**
103     * Check if the value is within a specified range.
104     *
105     * @param value The value validation is being performed on.
106     * @param min The minimum value of the range.
107     * @param max The maximum value of the range.
108     * @return <code>true</code> if the value is within the
109     *         specified range.
110     */
111    public boolean isInRange(Number value, Number min, Number max) {
112        return (minValue(value, min) && maxValue(value, max));
113    }
114
115    /**
116     * Check if the value is greater than or equal to a minimum.
117     *
118     * @param value The value validation is being performed on.
119     * @param min The minimum value.
120     * @return <code>true</code> if the value is greater than
121     *         or equal to the minimum.
122     */
123    public boolean minValue(Number value, Number min) {
124        if (isAllowFractions()) {
125            return (value.doubleValue() >= min.doubleValue());
126        } else {
127            return (value.longValue() >= min.longValue());
128        }
129    }
130
131    /**
132     * Check if the value is less than or equal to a maximum.
133     *
134     * @param value The value validation is being performed on.
135     * @param max The maximum value.
136     * @return <code>true</code> if the value is less than
137     *         or equal to the maximum.
138     */
139    public boolean maxValue(Number value, Number max) {
140        if (isAllowFractions()) {
141            return (value.doubleValue() <= max.doubleValue());
142        } else {
143            return (value.longValue() <= max.longValue());
144        }
145    }
146
147    /**
148     * <p>Parse the value using the specified pattern.</p>
149     *
150     * @param value The value validation is being performed on.
151     * @param pattern The pattern used to validate the value against, or the
152     *        default for the <code>Locale</code> if <code>null</code>.
153     * @param locale The locale to use for the date format, system default if null.
154     * @return The parsed value if valid or <code>null</code> if invalid.
155     */
156    protected Object parse(String value, String pattern, Locale locale) {
157
158        value = (value == null ? null : value.trim());
159        if (value == null || value.length() == 0) {
160            return null;
161        }
162        Format formatter = getFormat(pattern, locale);
163        return parse(value, formatter);
164
165    }
166
167    /**
168     * <p>Process the parsed value, performing any further validation
169     *    and type conversion required.</p>
170     *
171     * @param value The parsed object created.
172     * @param formatter The Format used to parse the value with.
173     * @return The parsed value converted to the appropriate type
174     *         if valid or <code>null</code> if invalid.
175     */
176    protected abstract Object processParsedValue(Object value, Format formatter);
177
178    /**
179     * <p>Returns a <code>NumberFormat</code> for the specified <i>pattern</i>
180     *    and/or <code>Locale</code>.</p>
181     *
182     * @param pattern The pattern used to validate the value against or
183     *        <code>null</code> to use the default for the <code>Locale</code>.
184     * @param locale The locale to use for the currency format, system default if null.
185     * @return The <code>NumberFormat</code> to created.
186     */
187    protected Format getFormat(String pattern, Locale locale) {
188
189        NumberFormat formatter = null;
190        boolean usePattern = (pattern != null && pattern.length() > 0);
191        if (!usePattern) {
192            formatter = (NumberFormat)getFormat(locale);
193        } else if (locale == null) {
194            formatter =  new DecimalFormat(pattern);
195        } else {
196            DecimalFormatSymbols symbols = new DecimalFormatSymbols(locale);
197            formatter = new DecimalFormat(pattern, symbols);
198        }
199
200        if (determineScale(formatter) == 0) {
201            formatter.setParseIntegerOnly(true);
202        }
203        return formatter;
204    }
205
206    /**
207     * <p>Returns the <i>multiplier</i> of the <code>NumberFormat</code>.</p>
208     *
209     * @param format The <code>NumberFormat</code> to determine the
210     *        multiplier of.
211     * @return The multiplying factor for the format..
212     */
213    protected int determineScale(NumberFormat format) {
214        if (!isStrict()) {
215            return -1;
216        }
217        if (!isAllowFractions() || format.isParseIntegerOnly()) {
218            return 0;
219        }
220        int minimumFraction = format.getMinimumFractionDigits();
221        int maximumFraction = format.getMaximumFractionDigits();
222        if (minimumFraction != maximumFraction) {
223            return -1;
224        }
225        int scale = minimumFraction;
226        if (format instanceof DecimalFormat) {
227            int multiplier = ((DecimalFormat)format).getMultiplier();
228            if (multiplier == 100) {
229                scale += 2;
230            } else if (multiplier == 1000) {
231                scale += 3;
232            }
233        } else if (formatType == PERCENT_FORMAT) {
234            scale += 2;
235        }
236        return scale;
237    }
238
239    /**
240     * <p>Returns a <code>NumberFormat</code> for the specified Locale.</p>
241     *
242     * @param locale The locale a <code>NumberFormat</code> is required for,
243     *   system default if null.
244     * @return The <code>NumberFormat</code> to created.
245     */
246    protected Format getFormat(Locale locale) {
247        NumberFormat formatter = null;
248        switch (formatType) {
249        case CURRENCY_FORMAT:
250            if (locale == null) {
251                formatter = NumberFormat.getCurrencyInstance();
252            } else {
253                formatter = NumberFormat.getCurrencyInstance(locale);
254            }
255            break;
256        case PERCENT_FORMAT:
257            if (locale == null) {
258                formatter = NumberFormat.getPercentInstance();
259            } else {
260                formatter = NumberFormat.getPercentInstance(locale);
261            }
262            break;
263        default:
264            if (locale == null) {
265                formatter = NumberFormat.getInstance();
266            } else {
267                formatter = NumberFormat.getInstance(locale);
268            }
269            break;
270        }
271        return formatter;
272    }
273}