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     */
017    package org.apache.commons.validator.routines;
018    
019    import java.text.DateFormat;
020    import java.text.Format;
021    import java.util.Calendar;
022    import java.util.Locale;
023    import java.util.TimeZone;
024    
025    /**
026     * <p><b>Time Validation</b> and Conversion routines (<code>java.util.Calendar</code>).</p>
027     *
028     * <p>This validator provides a number of methods for validating/converting
029     *    a <code>String</code> time value to a <code>java.util.Calendar</code> using 
030     *    <code>java.text.DateFormat</code> to parse either:</p>
031     *    <ul>
032     *       <li>using the default format for the default <code>Locale</code></li>
033     *       <li>using a specified pattern with the default <code>Locale</code></li>
034     *       <li>using the default format for a specified <code>Locale</code></li>
035     *       <li>using a specified pattern with a specified <code>Locale</code></li>
036     *    </ul>
037     *    
038     * <p>For each of the above mechanisms, conversion method (i.e the  
039     *    <code>validate</code> methods) implementations are provided which
040     *    either use the default <code>TimeZone</code> or allow the 
041     *    <code>TimeZone</code> to be specified.</p>
042     *    
043     * <p>Use one of the <code>isValid()</code> methods to just validate or
044     *    one of the <code>validate()</code> methods to validate and receive a
045     *    <i>converted</i> <code>Calendar</code> value for the time.</p>
046     *
047     * <p>Implementations of the <code>validate()</code> method are provided
048     *    to create <code>Calendar</code> objects for different <i>time zones</i>
049     *    if the system default is not appropriate.</p>
050     *    
051     * <p>Alternatively the CalendarValidator's <code>adjustToTimeZone()</code> method
052     *    can be used to adjust the <code>TimeZone</code> of the <code>Calendar</code>
053     *    object afterwards.</p> 
054     * 
055     * <p>Once a value has been sucessfully converted the following
056     *    methods can be used to perform various time comparison checks:</p>
057     *    <ul>
058     *       <li><code>compareTime()</code> compares the hours, minutes, seconds
059     *           and milliseconds of two calendars, returing 0, -1 or +1 indicating
060     *           whether the first time is equal, before or after the second.</li>
061     *       <li><code>compareSeconds()</code> compares the hours, minutes and
062     *           seconds of two times, returing 0, -1 or +1 indicating
063     *           whether the first is equal to, before or after the second.</li>
064     *       <li><code>compareMinutes()</code> compares the hours and minutes
065     *           two times, returing 0, -1 or +1 indicating
066     *           whether the first is equal to, before or after the second.</li>
067     *       <li><code>compareHours()</code> compares the hours
068     *           of two times, returing 0, -1 or +1 indicating
069     *           whether the first is equal to, before or after the second.</li>
070     *    </ul>
071     * 
072     * <p>So that the same mechanism used for parsing an <i>input</i> value 
073     *    for validation can be used to format <i>output</i>, corresponding
074     *    <code>format()</code> methods are also provided. That is you can 
075     *    format either:</p>
076     *    <ul>
077     *       <li>using a specified pattern</li>
078     *       <li>using the format for a specified <code>Locale</code></li>
079     *       <li>using the format for the <i>default</i> <code>Locale</code></li>
080     *    </ul>
081     *
082     * @version $Revision: 493905 $ $Date: 2007-01-08 03:11:38 +0100 (Mo, 08. Jan 2007) $
083     * @since Validator 1.3.0
084     */
085    public class TimeValidator extends AbstractCalendarValidator {
086    
087        private static final TimeValidator VALIDATOR = new TimeValidator();
088    
089        /**
090         * Return a singleton instance of this validator.
091         * @return A singleton instance of the TimeValidator.
092         */
093        public static TimeValidator getInstance() {
094            return VALIDATOR;
095        }
096    
097        /**
098         * Construct a <i>strict</i> instance with <i>short</i>
099         * time style.
100         */
101        public TimeValidator() {
102            this(true, DateFormat.SHORT);
103        }
104    
105        /**
106         * Construct an instance with the specified <i>strict</i>
107         * and <i>time style</i> parameters.
108         * 
109         * @param strict <code>true</code> if strict 
110         *        <code>Format</code> parsing should be used.
111         * @param timeStyle the time style to use for Locale validation.
112         */
113        public TimeValidator(boolean strict, int timeStyle) {
114            super(strict, -1, timeStyle);
115        }
116    
117        /**
118         * <p>Validate/convert a time using the default <code>Locale</code>
119         *    and <code>TimeZone</code>. 
120         *
121         * @param value The value validation is being performed on.
122         * @return The parsed <code>Calendar</code> if valid or <code>null</code>
123         *  if invalid.
124         */
125        public Calendar validate(String value) {
126            return (Calendar)parse(value, (String)null, (Locale)null, (TimeZone)null);
127        }
128    
129        /**
130         * <p>Validate/convert a time using the specified <code>TimeZone</code>
131         *    and default <code>Locale</code>.
132         *
133         * @param value The value validation is being performed on.
134         * @param timeZone The Time Zone used to parse the time, system default if null.
135         * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid.
136         */
137        public Calendar validate(String value, TimeZone timeZone) {
138            return (Calendar)parse(value, (String)null, (Locale)null, timeZone);
139        }
140    
141        /**
142         * <p>Validate/convert a time using the specified <i>pattern</i> and
143         *    default <code>TimeZone</code>.
144         *
145         * @param value The value validation is being performed on.
146         * @param pattern The pattern used to validate the value against.
147         * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid.
148         */
149        public Calendar validate(String value, String pattern) {
150            return (Calendar)parse(value, pattern, (Locale)null, (TimeZone)null);
151        }
152    
153        /**
154         * <p>Validate/convert a time using the specified <i>pattern</i>
155         *    and <code>TimeZone</code>.
156         *
157         * @param value The value validation is being performed on.
158         * @param pattern The pattern used to validate the value against.
159         * @param timeZone The Time Zone used to parse the time, system default if null.
160         * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid.
161         */
162        public Calendar validate(String value, String pattern, TimeZone timeZone) {
163            return (Calendar)parse(value, pattern, (Locale)null, timeZone);
164        }
165    
166        /**
167         * <p>Validate/convert a time using the specified <code>Locale</code>
168         *    default <code>TimeZone</code>.
169         *
170         * @param value The value validation is being performed on.
171         * @param locale The locale to use for the time format, system default if null.
172         * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid.
173         */
174        public Calendar validate(String value, Locale locale) {
175            return (Calendar)parse(value, (String)null, locale, (TimeZone)null);
176        }
177    
178        /**
179         * <p>Validate/convert a time using the specified specified <code>Locale</code>
180         *    and <code>TimeZone</code>.
181         *
182         * @param value The value validation is being performed on.
183         * @param locale The locale to use for the time format, system default if null.
184         * @param timeZone The Time Zone used to parse the time, system default if null.
185         * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid.
186         */
187        public Calendar validate(String value, Locale locale, TimeZone timeZone) {
188            return (Calendar)parse(value, (String)null, locale, timeZone);
189        }
190    
191        /**
192         * <p>Validate/convert a time using the specified pattern and <code>Locale</code>
193         *    and the default <code>TimeZone</code>.
194         *
195         * @param value The value validation is being performed on.
196         * @param pattern The pattern used to validate the value against, or the
197         *        default for the <code>Locale</code> if <code>null</code>.
198         * @param locale The locale to use for the date format, system default if null.
199         * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid.
200         */
201        public Calendar validate(String value, String pattern, Locale locale) {
202            return (Calendar)parse(value, pattern, locale, (TimeZone)null);
203        }
204    
205        /**
206         * <p>Validate/convert a time using the specified pattern, <code>Locale</code>
207         *    and <code>TimeZone</code>.
208         *
209         * @param value The value validation is being performed on.
210         * @param pattern The pattern used to validate the value against, or the
211         *        default for the <code>Locale</code> if <code>null</code>.
212         * @param locale The locale to use for the date format, system default if null.
213         * @param timeZone The Time Zone used to parse the date, system default if null.
214         * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid.
215         */
216        public Calendar validate(String value, String pattern, Locale locale, TimeZone timeZone) {
217            return (Calendar)parse(value, pattern, locale, timeZone);
218        }
219    
220        /**
221         * <p>Compare Times (hour, minute, second and millisecond - not date).</p>
222         * 
223         * @param value The <code>Calendar</code> value to check.
224         * @param compare The <code>Calendar</code> to compare the value to.
225         * @return Zero if the hours are equal, -1 if first
226         * time is less than the seconds and +1 if the first
227         * time is greater than.
228         */
229        public int compareTime(Calendar value, Calendar compare) {
230            return compareTime(value, compare, Calendar.MILLISECOND);
231        }
232    
233        /**
234         * <p>Compare Seconds (hours, minutes and seconds).</p>
235         * 
236         * @param value The <code>Calendar</code> value to check.
237         * @param compare The <code>Calendar</code> to compare the value to.
238         * @return Zero if the hours are equal, -1 if first
239         * parameter's seconds are less than the seconds and +1 if the first
240         * parameter's seconds are greater than.
241         */
242        public int compareSeconds(Calendar value, Calendar compare) {
243            return compareTime(value, compare, Calendar.SECOND);
244        }
245    
246        /**
247         * <p>Compare Minutes (hours and minutes).</p>
248         * 
249         * @param value The <code>Calendar</code> value to check.
250         * @param compare The <code>Calendar</code> to compare the value to.
251         * @return Zero if the hours are equal, -1 if first
252         * parameter's minutes are less than the seconds and +1 if the first
253         * parameter's minutes are greater than.
254         */
255        public int compareMinutes(Calendar value, Calendar compare) {
256            return compareTime(value, compare, Calendar.MINUTE);
257        }
258    
259        /**
260         * <p>Compare Hours.</p>
261         * 
262         * @param value The <code>Calendar</code> value to check.
263         * @param compare The <code>Calendar</code> to compare the value to.
264         * @return Zero if the hours are equal, -1 if first
265         * parameter's hour is less than the seconds and +1 if the first
266         * parameter's hour is greater than.
267         */
268        public int compareHours(Calendar value, Calendar compare) {
269            return compareTime(value, compare, Calendar.HOUR_OF_DAY);
270        }
271    
272        /**
273         * <p>Convert the parsed <code>Date</code> to a <code>Calendar</code>.</p>
274         * 
275         * @param value The parsed <code>Date</code> object created.
276         * @param formatter The Format used to parse the value with.
277         * @return The parsed value converted to a <code>Calendar</code>.
278         */
279        protected Object processParsedValue(Object value, Format formatter) {
280            return ((DateFormat)formatter).getCalendar();
281        }
282    }