com.twelvemonkeys.util.convert.DateConverter Maven / Gradle / Ivy
/*
* Copyright (c) 2008, Harald Kuhr
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* * Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.twelvemonkeys.util.convert;
import com.twelvemonkeys.lang.BeanUtil;
import com.twelvemonkeys.lang.StringUtil;
import java.lang.reflect.InvocationTargetException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
/**
* Converts strings to dates and back.
*
* This class has a static cache of {@code DateFormats}, to avoid
* creation and parsing of date formats every time one is used.
*
*
* @author Harald Kuhr
* @author last modified by $Author: haku $
* @version $Id: //depot/branches/personal/haraldk/twelvemonkeys/release-2/twelvemonkeys-core/src/main/java/com/twelvemonkeys/util/convert/DateConverter.java#2 $
*/
public class DateConverter extends NumberConverter {
/** Creates a {@code DateConverter} */
public DateConverter() {
}
/**
* Converts the string to a date, using the given format for parsing.
*
* @param pString the string to convert.
* @param pType the type to convert to. {@code java.util.Date} and
* subclasses allowed.
* @param pFormat the format used for parsing. Must be a legal
* {@code SimpleDateFormat} format, or {@code null} which will use the
* default format.
*
* @return the object created from the given string. May safely be typecast
* to {@code java.util.Date}
*
* @see Date
* @see java.text.DateFormat
*
* @throws ConversionException
*/
public Object toObject(String pString, Class pType, String pFormat) throws ConversionException {
if (StringUtil.isEmpty(pString))
return null;
try {
DateFormat format;
if (pFormat == null) {
// Use system default format, using default locale
format = DateFormat.getDateTimeInstance();
}
else {
// Get format from cache
format = getDateFormat(pFormat);
}
Date date = StringUtil.toDate(pString, format);
// Allow for conversion to Date subclasses (ie. java.sql.*)
if (pType != Date.class) {
try {
date = (Date) BeanUtil.createInstance(pType, new Long(date.getTime()));
}
catch (ClassCastException e) {
throw new TypeMismathException(pType);
}
catch (InvocationTargetException e) {
throw new ConversionException(e);
}
}
return date;
}
catch (RuntimeException rte) {
throw new ConversionException(rte);
}
}
/**
* Converts the object to a string, using the given format
*
* @param pObject the object to convert.
* @param pFormat the format used for conversion. Must be a legal
* {@code SimpleDateFormat} format, or {@code null} which will use the
* default format.
*
* @return the string representation of the object, on the correct format.
*
* @throws ConversionException if the object is not a subclass of
* {@code java.util.Date}
*
* @see Date
* @see java.text.DateFormat
*/
public String toString(Object pObject, String pFormat) throws ConversionException {
if (pObject == null)
return null;
if (!(pObject instanceof Date)) {
throw new TypeMismathException(pObject.getClass());
}
try {
// Convert to string, default way
if (StringUtil.isEmpty(pFormat)) {
return DateFormat.getDateTimeInstance().format(pObject);
}
// Convert to string, using format
DateFormat format = getDateFormat(pFormat);
return format.format(pObject);
}
catch (RuntimeException rte) {
throw new ConversionException(rte);
}
}
private DateFormat getDateFormat(String pFormat) {
return (DateFormat) getFormat(SimpleDateFormat.class, pFormat, Locale.US);
}
}