Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.commons.validator.routines; import java.text.DateFormat; import java.text.Format; import java.util.Calendar; import java.util.Locale; import java.util.TimeZone; /** * <p> * <b>Calendar Validation</b> and Conversion routines (<code>java.util.Calendar</code>). * </p> * * <p> * This validator provides a number of methods for validating/converting a <code>String</code> date value to a * <code>java.util.Calendar</code> using <code>java.text.DateFormat</code> to parse either: * </p> * <ul> * <li>using the default format for the default <code>Locale</code></li> * <li>using a specified pattern with the default <code>Locale</code></li> * <li>using the default format for a specified <code>Locale</code></li> * <li>using a specified pattern with a specified <code>Locale</code></li> * </ul> * * <p> * For each of the above mechanisms, conversion method (i.e the <code>validate</code> methods) implementations are provided which * either use the default <code>TimeZone</code> or allow the <code>TimeZone</code> to be specified. * </p> * * <p> * Use one of the <code>isValid()</code> methods to just validate or one of the <code>validate()</code> methods to validate and * receive a <i>converted</i> <code>Calendar</code> value. * </p> * * <p> * Implementations of the <code>validate()</code> method are provided to create <code>Calendar</code> objects for different * <i>time zones</i> if the system default is not appropriate. * </p> * * <p> * Alternatively the CalendarValidator's <code>adjustToTimeZone()</code> method can be used to adjust the <code>TimeZone</code> of * the <code>Calendar</code> object afterwards. * </p> * * <p> * Once a value has been sucessfully converted the following methods can be used to perform various date comparison checks: * </p> * <ul> * <li><code>compareDates()</code> compares the day, month and year of two calendars, returing 0, -1 or +1 indicating whether the * first date is equal, before or after the second.</li> * <li><code>compareWeeks()</code> compares the week and year of two calendars, returing 0, -1 or +1 indicating whether the first * week is equal, before or after the second.</li> * <li><code>compareMonths()</code> compares the month and year of two calendars, returing 0, -1 or +1 indicating whether the * first month is equal, before or after the second.</li> * <li><code>compareQuarters()</code> compares the quarter and year of two calendars, returing 0, -1 or +1 indicating whether the * first quarter is equal, before or after the second.</li> * <li><code>compareYears()</code> compares the year of two calendars, returing 0, -1 or +1 indicating whether the first year is * equal, before or after the second.</li> * </ul> * * <p> * So that the same mechanism used for parsing an <i>input</i> value for validation can be used to format <i>output</i>, * corresponding <code>format()</code> methods are also provided. That is you can format either: * </p> * <ul> * <li>using a specified pattern</li> * <li>using the format for a specified <code>Locale</code></li> * <li>using the format for the <i>default</i> <code>Locale</code></li> * </ul> * * @version $Revision: 493905 $ $Date: 2007-01-08 02:11:38 +0000 (Seg, 08 Jan 2007) $ * @since Validator 1.3.0 */ public class CalendarValidator extends AbstractCalendarValidator { private static final CalendarValidator VALIDATOR = new CalendarValidator(); /** * Return a singleton instance of this validator. * * @return A singleton instance of the CalendarValidator. */ public static CalendarValidator getInstance() { return VALIDATOR; } /** * Construct a <i>strict</i> instance with <i>short</i> * date style. */ public CalendarValidator() { this(true, DateFormat.SHORT); } /** * Construct an instance with the specified <i>strict</i> * and <i>date style</i> parameters. * * @param strict <code>true</code> if strict <code>Format</code> parsing should be used. * @param dateStyle the date style to use for Locale validation. */ public CalendarValidator(boolean strict, int dateStyle) { super(strict, dateStyle, -1); } /** * <p> * Validate/convert a <code>Calendar</code> using the default <code>Locale</code> and <code>TimeZone</code>. * * @param value The value validation is being performed on. * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid. */ public Calendar validate(String value) { return (Calendar) parse(value, (String) null, (Locale) null, (TimeZone) null); } /** * <p> * Validate/convert a <code>Calendar</code> using the specified <code>TimeZone</code> and default <code>Locale</code>. * * @param value The value validation is being performed on. * @param timeZone The Time Zone used to parse the date, system default if null. * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid. */ public Calendar validate(String value, TimeZone timeZone) { return (Calendar) parse(value, (String) null, (Locale) null, timeZone); } /** * <p> * Validate/convert a <code>Calendar</code> using the specified <i>pattern</i> and default <code>TimeZone</code>. * * @param value The value validation is being performed on. * @param pattern The pattern used to validate the value against. * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid. */ public Calendar validate(String value, String pattern) { return (Calendar) parse(value, pattern, (Locale) null, (TimeZone) null); } /** * <p> * Validate/convert a <code>Calendar</code> using the specified <i>pattern</i> and <code>TimeZone</code>. * * @param value The value validation is being performed on. * @param pattern The pattern used to validate the value against. * @param timeZone The Time Zone used to parse the date, system default if null. * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid. */ public Calendar validate(String value, String pattern, TimeZone timeZone) { return (Calendar) parse(value, pattern, (Locale) null, timeZone); } /** * <p> * Validate/convert a <code>Calendar</code> using the specified <code>Locale</code> and default <code>TimeZone</code>. * * @param value The value validation is being performed on. * @param locale The locale to use for the date format, system default if null. * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid. */ public Calendar validate(String value, Locale locale) { return (Calendar) parse(value, (String) null, locale, (TimeZone) null); } /** * <p> * Validate/convert a <code>Calendar</code> using the specified <code>Locale</code> and <code>TimeZone</code>. * * @param value The value validation is being performed on. * @param locale The locale to use for the date format, system default if null. * @param timeZone The Time Zone used to parse the date, system default if null. * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid. */ public Calendar validate(String value, Locale locale, TimeZone timeZone) { return (Calendar) parse(value, (String) null, locale, timeZone); } /** * <p> * Validate/convert a <code>Calendar</code> using the specified pattern and <code>Locale</code> and the default * <code>TimeZone</code>. * * @param value The value validation is being performed on. * @param pattern The pattern used to validate the value against, or the * default for the <code>Locale</code> if <code>null</code>. * @param locale The locale to use for the date format, system default if null. * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid. */ public Calendar validate(String value, String pattern, Locale locale) { return (Calendar) parse(value, pattern, locale, (TimeZone) null); } /** * <p> * Validate/convert a <code>Calendar</code> using the specified pattern, and <code>Locale</code> and <code>TimeZone</code>. * * @param value The value validation is being performed on. * @param pattern The pattern used to validate the value against, or the * default for the <code>Locale</code> if <code>null</code>. * @param locale The locale to use for the date format, system default if null. * @param timeZone The Time Zone used to parse the date, system default if null. * @return The parsed <code>Calendar</code> if valid or <code>null</code> if invalid. */ public Calendar validate(String value, String pattern, Locale locale, TimeZone timeZone) { return (Calendar) parse(value, pattern, locale, timeZone); } /** * <p> * Adjusts a Calendar's value to a different TimeZone. * </p> * * @param value The value to adjust. * @param timeZone The new time zone to use to adjust the Calendar to. */ public static void adjustToTimeZone(Calendar value, TimeZone timeZone) { if (value.getTimeZone().hasSameRules(timeZone)) { value.setTimeZone(timeZone); } else { int year = value.get(Calendar.YEAR); int month = value.get(Calendar.MONTH); int date = value.get(Calendar.DATE); int hour = value.get(Calendar.HOUR_OF_DAY); int minute = value.get(Calendar.MINUTE); value.setTimeZone(timeZone); value.set(year, month, date, hour, minute); } } /** * <p> * Compare Dates (day, month and year - not time). * </p> * * @param value The <code>Calendar</code> value to check. * @param compare The <code>Calendar</code> to compare the value to. * @return Zero if the dates are equal, -1 if first * date is less than the seconds and +1 if the first * date is greater than. */ public int compareDates(Calendar value, Calendar compare) { return compare(value, compare, Calendar.DATE); } /** * <p> * Compare Weeks (week and year). * </p> * * @param value The <code>Calendar</code> value to check. * @param compare The <code>Calendar</code> to compare the value to. * @return Zero if the weeks are equal, -1 if first * parameter's week is less than the seconds and +1 if the first * parameter's week is greater than. */ public int compareWeeks(Calendar value, Calendar compare) { return compare(value, compare, Calendar.WEEK_OF_YEAR); } /** * <p> * Compare Months (month and year). * </p> * * @param value The <code>Calendar</code> value to check. * @param compare The <code>Calendar</code> to compare the value to. * @return Zero if the months are equal, -1 if first * parameter's month is less than the seconds and +1 if the first * parameter's month is greater than. */ public int compareMonths(Calendar value, Calendar compare) { return compare(value, compare, Calendar.MONTH); } /** * <p> * Compare Quarters (quarter and year). * </p> * * @param value The <code>Calendar</code> value to check. * @param compare The <code>Calendar</code> to check the value against. * @return Zero if the quarters are equal, -1 if first * parameter's quarter is less than the seconds and +1 if the first * parameter's quarter is greater than. */ public int compareQuarters(Calendar value, Calendar compare) { return compareQuarters(value, compare, 1); } /** * <p> * Compare Quarters (quarter and year). * </p> * * @param value The <code>Calendar</code> value to check. * @param compare The <code>Calendar</code> to compare the value to. * @param monthOfFirstQuarter The month that the first quarter starts. * @return Zero if the quarters are equal, -1 if first * parameter's quarter is less than the seconds and +1 if the first * parameter's quarter is greater than. */ @Override public int compareQuarters(Calendar value, Calendar compare, int monthOfFirstQuarter) { return super.compareQuarters(value, compare, monthOfFirstQuarter); } /** * <p> * Compare Years. * </p> * * @param value The <code>Calendar</code> value to check. * @param compare The <code>Calendar</code> to compare the value to. * @return Zero if the years are equal, -1 if first * parameter's year is less than the seconds and +1 if the first * parameter's year is greater than. */ public int compareYears(Calendar value, Calendar compare) { return compare(value, compare, Calendar.YEAR); } /** * <p> * Convert the parsed <code>Date</code> to a <code>Calendar</code>. * </p> * * @param value The parsed <code>Date</code> object created. * @param formatter The Format used to parse the value with. * @return The parsed value converted to a <code>Calendar</code>. */ @Override protected Object processParsedValue(Object value, Format formatter) { return ((DateFormat) formatter).getCalendar(); } }