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/* * 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 javadz.beanutils.locale.converters; import javadz.beanutils.ConversionException; import javadz.beanutils.locale.BaseLocaleConverter; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import java.text.ParseException; import java.text.ParsePosition; import java.text.SimpleDateFormat; import java.text.DateFormat; import java.text.DateFormatSymbols; import java.util.Locale; /** * <p>Standard {@link org.apache.commons.beanutils.locale.LocaleConverter} * implementation that converts an incoming * locale-sensitive String into a <code>java.util.Date</code> object, * optionally using a default value or throwing a * {@link org.apache.commons.beanutils.ConversionException} * if a conversion error occurs.</p> * * @author Yauheny Mikulski * @author Michael Szlapa */ public class DateLocaleConverter extends BaseLocaleConverter { // ----------------------------------------------------- Instance Variables /** All logging goes through this logger */ private Log log = LogFactory.getLog(DateLocaleConverter.class); /** Should the date conversion be lenient? */ boolean isLenient = false; /** * Default Pattern Characters * */ private static final String DEFAULT_PATTERN_CHARS = DateLocaleConverter.initDefaultChars(); // ----------------------------------------------------------- Constructors /** * Create a {@link org.apache.commons.beanutils.locale.LocaleConverter} * that will throw a {@link org.apache.commons.beanutils.ConversionException} * if a conversion error occurs. The locale is the default locale for * this instance of the Java Virtual Machine and an unlocalized pattern is used * for the convertion. * */ public DateLocaleConverter() { this(false); } /** * Create a {@link org.apache.commons.beanutils.locale.LocaleConverter} * that will throw a {@link org.apache.commons.beanutils.ConversionException} * if a conversion error occurs. The locale is the default locale for * this instance of the Java Virtual Machine. * * @param locPattern Indicate whether the pattern is localized or not */ public DateLocaleConverter(boolean locPattern) { this(Locale.getDefault(), locPattern); } /** * Create a {@link org.apache.commons.beanutils.locale.LocaleConverter} * that will throw a {@link org.apache.commons.beanutils.ConversionException} * if a conversion error occurs. An unlocalized pattern is used for the convertion. * * @param locale The locale */ public DateLocaleConverter(Locale locale) { this(locale, false); } /** * Create a {@link org.apache.commons.beanutils.locale.LocaleConverter} * that will throw a {@link org.apache.commons.beanutils.ConversionException} * if a conversion error occurs. * * @param locale The locale * @param locPattern Indicate whether the pattern is localized or not */ public DateLocaleConverter(Locale locale, boolean locPattern) { this(locale, (String) null, locPattern); } /** * Create a {@link org.apache.commons.beanutils.locale.LocaleConverter} * that will throw a {@link org.apache.commons.beanutils.ConversionException} * if a conversion error occurs. An unlocalized pattern is used for the convertion. * * @param locale The locale * @param pattern The convertion pattern */ public DateLocaleConverter(Locale locale, String pattern) { this(locale, pattern, false); } /** * Create a {@link org.apache.commons.beanutils.locale.LocaleConverter} * that will throw a {@link org.apache.commons.beanutils.ConversionException} * if a conversion error occurs. * * @param locale The locale * @param pattern The convertion pattern * @param locPattern Indicate whether the pattern is localized or not */ public DateLocaleConverter(Locale locale, String pattern, boolean locPattern) { super(locale, pattern, locPattern); } /** * Create a {@link org.apache.commons.beanutils.locale.LocaleConverter} * that will return the specified default value * if a conversion error occurs. The locale is the default locale for * this instance of the Java Virtual Machine and an unlocalized pattern is used * for the convertion. * * @param defaultValue The default value to be returned */ public DateLocaleConverter(Object defaultValue) { this(defaultValue, false); } /** * Create a {@link org.apache.commons.beanutils.locale.LocaleConverter} * that will return the specified default value * if a conversion error occurs. The locale is the default locale for * this instance of the Java Virtual Machine. * * @param defaultValue The default value to be returned * @param locPattern Indicate whether the pattern is localized or not */ public DateLocaleConverter(Object defaultValue, boolean locPattern) { this(defaultValue, Locale.getDefault(), locPattern); } /** * Create a {@link org.apache.commons.beanutils.locale.LocaleConverter} * that will return the specified default value * if a conversion error occurs. An unlocalized pattern is used for the convertion. * * @param defaultValue The default value to be returned * @param locale The locale */ public DateLocaleConverter(Object defaultValue, Locale locale) { this(defaultValue, locale, false); } /** * Create a {@link org.apache.commons.beanutils.locale.LocaleConverter} * that will return the specified default value * if a conversion error occurs. * * @param defaultValue The default value to be returned * @param locale The locale * @param locPattern Indicate whether the pattern is localized or not */ public DateLocaleConverter(Object defaultValue, Locale locale, boolean locPattern) { this(defaultValue, locale, null, locPattern); } /** * Create a {@link org.apache.commons.beanutils.locale.LocaleConverter} * that will return the specified default value * if a conversion error occurs. An unlocalized pattern is used for the convertion. * * @param defaultValue The default value to be returned * @param locale The locale * @param pattern The convertion pattern */ public DateLocaleConverter(Object defaultValue, Locale locale, String pattern) { this(defaultValue, locale, pattern, false); } /** * Create a {@link org.apache.commons.beanutils.locale.LocaleConverter} * that will return the specified default value * if a conversion error occurs. * * @param defaultValue The default value to be returned * @param locale The locale * @param pattern The convertion pattern * @param locPattern Indicate whether the pattern is localized or not */ public DateLocaleConverter(Object defaultValue, Locale locale, String pattern, boolean locPattern) { super(defaultValue, locale, pattern, locPattern); } // --------------------------------------------------------- Methods /** * Returns whether date formatting is lenient. * * @return true if the <code>DateFormat</code> used for formatting is lenient * @see java.text.DateFormat#isLenient */ public boolean isLenient() { return isLenient; } /** * Specify whether or not date-time parsing should be lenient. * * @param lenient true if the <code>DateFormat</code> used for formatting should be lenient * @see java.text.DateFormat#setLenient */ public void setLenient(boolean lenient) { isLenient = lenient; } // --------------------------------------------------------- Methods /** * Convert the specified locale-sensitive input object into an output object of the * specified type. * * @param value The input object to be converted * @param pattern The pattern is used for the convertion * @return the converted Date value * * @exception org.apache.commons.beanutils.ConversionException * if conversion cannot be performed successfully * @throws ParseException if an error occurs parsing */ protected Object parse(Object value, String pattern) throws ParseException { // Handle Date if (value instanceof java.util.Date) { return value; } // Handle Calendar if (value instanceof java.util.Calendar) { return ((java.util.Calendar) value).getTime(); } if (locPattern) { pattern = convertLocalizedPattern(pattern, locale); } // Create Formatter - use default if pattern is null DateFormat formatter = pattern == null ? DateFormat.getDateInstance(DateFormat.SHORT, locale) : new SimpleDateFormat(pattern, locale); formatter.setLenient(isLenient); // Parse the Date ParsePosition pos = new ParsePosition(0); String strValue = value.toString(); Object parsedValue = formatter.parseObject(strValue, pos); if (pos.getErrorIndex() > -1) { throw new ConversionException("Error parsing date '" + value + "' at position=" + pos.getErrorIndex()); } if (pos.getIndex() < strValue.length()) { throw new ConversionException( "Date '" + value + "' contains unparsed characters from position=" + pos.getIndex()); } return parsedValue; } /** * Convert a pattern from a localized format to the default format. * * @param locale The locale * @param localizedPattern The pattern in 'local' symbol format * @return pattern in 'default' symbol format */ private String convertLocalizedPattern(String localizedPattern, Locale locale) { if (localizedPattern == null) { return null; } // Note that this is a little obtuse. // However, it is the best way that anyone can come up with // that works with some 1.4 series JVM. // Get the symbols for the localized pattern DateFormatSymbols localizedSymbols = new DateFormatSymbols(locale); String localChars = localizedSymbols.getLocalPatternChars(); if (DEFAULT_PATTERN_CHARS.equals(localChars)) { return localizedPattern; } // Convert the localized pattern to default String convertedPattern = null; try { convertedPattern = convertPattern(localizedPattern, localChars, DEFAULT_PATTERN_CHARS); } catch (Exception ex) { log.debug("Converting pattern '" + localizedPattern + "' for " + locale, ex); } return convertedPattern; } /** * <p>Converts a Pattern from one character set to another.</p> */ private String convertPattern(String pattern, String fromChars, String toChars) { StringBuffer converted = new StringBuffer(); boolean quoted = false; for (int i = 0; i < pattern.length(); ++i) { char thisChar = pattern.charAt(i); if (quoted) { if (thisChar == '\'') { quoted = false; } } else { if (thisChar == '\'') { quoted = true; } else if ((thisChar >= 'a' && thisChar <= 'z') || (thisChar >= 'A' && thisChar <= 'Z')) { int index = fromChars.indexOf(thisChar); if (index == -1) { throw new IllegalArgumentException("Illegal pattern character '" + thisChar + "'"); } thisChar = toChars.charAt(index); } } converted.append(thisChar); } if (quoted) { throw new IllegalArgumentException("Unfinished quote in pattern"); } return converted.toString(); } /** * This method is called at class initialization time to define the * value for constant member DEFAULT_PATTERN_CHARS. All other methods needing * this data should just read that constant. */ private static String initDefaultChars() { DateFormatSymbols defaultSymbols = new DateFormatSymbols(Locale.US); return defaultSymbols.getLocalPatternChars(); } }