org.springframework.format.datetime.DateFormatter Maven / Gradle / Ivy
/*
* Copyright 2002-2022 the original author or authors.
*
* Licensed 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
*
* https://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.springframework.format.datetime;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import java.util.Map;
import java.util.TimeZone;
import org.springframework.format.Formatter;
import org.springframework.format.annotation.DateTimeFormat;
import org.springframework.format.annotation.DateTimeFormat.ISO;
import org.springframework.lang.Nullable;
import org.springframework.util.ObjectUtils;
import org.springframework.util.StringUtils;
/**
* A formatter for {@link java.util.Date} types.
* Supports the configuration of an explicit date time pattern, timezone,
* locale, and fallback date time patterns for lenient parsing.
*
* @author Keith Donald
* @author Juergen Hoeller
* @author Phillip Webb
* @author Sam Brannen
* @since 3.0
* @see SimpleDateFormat
*/
public class DateFormatter implements Formatter {
private static final TimeZone UTC = TimeZone.getTimeZone("UTC");
private static final Map ISO_PATTERNS = Map.of(
ISO.DATE, "yyyy-MM-dd",
ISO.TIME, "HH:mm:ss.SSSXXX",
ISO.DATE_TIME, "yyyy-MM-dd'T'HH:mm:ss.SSSXXX");
@Nullable
private Object source;
@Nullable
private String pattern;
@Nullable
private String[] fallbackPatterns;
private int style = DateFormat.DEFAULT;
@Nullable
private String stylePattern;
@Nullable
private ISO iso;
@Nullable
private TimeZone timeZone;
private boolean lenient = false;
/**
* Create a new default {@code DateFormatter}.
*/
public DateFormatter() {
}
/**
* Create a new {@code DateFormatter} for the given date time pattern.
*/
public DateFormatter(String pattern) {
this.pattern = pattern;
}
/**
* Set the source of the configuration for this {@code DateFormatter} —
* for example, an instance of the {@link DateTimeFormat @DateTimeFormat}
* annotation if such an annotation was used to configure this {@code DateFormatter}.
* The supplied source object will only be used for descriptive purposes
* by invoking its {@code toString()} method — for example, when
* generating an exception message to provide further context.
* @param source the source of the configuration
* @since 5.3.5
*/
public void setSource(Object source) {
this.source = source;
}
/**
* Set the pattern to use to format date values.
*
If not specified, DateFormat's default style will be used.
*/
public void setPattern(String pattern) {
this.pattern = pattern;
}
/**
* Set additional patterns to use as a fallback in case parsing fails for the
* configured {@linkplain #setPattern pattern}, {@linkplain #setIso ISO format},
* {@linkplain #setStyle style}, or {@linkplain #setStylePattern style pattern}.
* @param fallbackPatterns the fallback parsing patterns
* @since 5.3.5
* @see DateTimeFormat#fallbackPatterns()
*/
public void setFallbackPatterns(String... fallbackPatterns) {
this.fallbackPatterns = fallbackPatterns;
}
/**
* Set the ISO format to use to format date values.
* @param iso the {@link ISO} format
* @since 3.2
*/
public void setIso(ISO iso) {
this.iso = iso;
}
/**
* Set the {@link DateFormat} style to use to format date values.
*
If not specified, DateFormat's default style will be used.
* @see DateFormat#DEFAULT
* @see DateFormat#SHORT
* @see DateFormat#MEDIUM
* @see DateFormat#LONG
* @see DateFormat#FULL
*/
public void setStyle(int style) {
this.style = style;
}
/**
* Set the two characters to use to format date values.
*
The first character is used for the date style; the second is used for
* the time style.
*
Supported characters:
*
* - 'S' = Small
* - 'M' = Medium
* - 'L' = Long
* - 'F' = Full
* - '-' = Omitted
*
* This method mimics the styles supported by Joda-Time.
* @param stylePattern two characters from the set {"S", "M", "L", "F", "-"}
* @since 3.2
*/
public void setStylePattern(String stylePattern) {
this.stylePattern = stylePattern;
}
/**
* Set the {@link TimeZone} to normalize the date values into, if any.
*/
public void setTimeZone(TimeZone timeZone) {
this.timeZone = timeZone;
}
/**
* Specify whether parsing is to be lenient. Default is {@code false}.
* With lenient parsing, the parser may allow inputs that do not precisely match the format.
* With strict parsing, inputs must match the format exactly.
*/
public void setLenient(boolean lenient) {
this.lenient = lenient;
}
@Override
public String print(Date date, Locale locale) {
return getDateFormat(locale).format(date);
}
@Override
public Date parse(String text, Locale locale) throws ParseException {
try {
return getDateFormat(locale).parse(text);
}
catch (ParseException ex) {
if (!ObjectUtils.isEmpty(this.fallbackPatterns)) {
for (String pattern : this.fallbackPatterns) {
try {
DateFormat dateFormat = configureDateFormat(new SimpleDateFormat(pattern, locale));
// Align timezone for parsing format with printing format if ISO is set.
if (this.iso != null && this.iso != ISO.NONE) {
dateFormat.setTimeZone(UTC);
}
return dateFormat.parse(text);
}
catch (ParseException ignoredException) {
// Ignore fallback parsing exceptions since the exception thrown below
// will include information from the "source" if available -- for example,
// the toString() of a @DateTimeFormat annotation.
}
}
}
if (this.source != null) {
ParseException parseException = new ParseException(
String.format("Unable to parse date time value \"%s\" using configuration from %s", text, this.source),
ex.getErrorOffset());
parseException.initCause(ex);
throw parseException;
}
// else rethrow original exception
throw ex;
}
}
protected DateFormat getDateFormat(Locale locale) {
return configureDateFormat(createDateFormat(locale));
}
private DateFormat configureDateFormat(DateFormat dateFormat) {
if (this.timeZone != null) {
dateFormat.setTimeZone(this.timeZone);
}
dateFormat.setLenient(this.lenient);
return dateFormat;
}
private DateFormat createDateFormat(Locale locale) {
if (StringUtils.hasLength(this.pattern)) {
return new SimpleDateFormat(this.pattern, locale);
}
if (this.iso != null && this.iso != ISO.NONE) {
String pattern = ISO_PATTERNS.get(this.iso);
if (pattern == null) {
throw new IllegalStateException("Unsupported ISO format " + this.iso);
}
SimpleDateFormat format = new SimpleDateFormat(pattern);
format.setTimeZone(UTC);
return format;
}
if (StringUtils.hasLength(this.stylePattern)) {
int dateStyle = getStylePatternForChar(0);
int timeStyle = getStylePatternForChar(1);
if (dateStyle != -1 && timeStyle != -1) {
return DateFormat.getDateTimeInstance(dateStyle, timeStyle, locale);
}
if (dateStyle != -1) {
return DateFormat.getDateInstance(dateStyle, locale);
}
if (timeStyle != -1) {
return DateFormat.getTimeInstance(timeStyle, locale);
}
throw new IllegalStateException("Unsupported style pattern '" + this.stylePattern + "'");
}
return DateFormat.getDateInstance(this.style, locale);
}
private int getStylePatternForChar(int index) {
if (this.stylePattern != null && this.stylePattern.length() > index) {
switch (this.stylePattern.charAt(index)) {
case 'S': return DateFormat.SHORT;
case 'M': return DateFormat.MEDIUM;
case 'L': return DateFormat.LONG;
case 'F': return DateFormat.FULL;
case '-': return -1;
}
}
throw new IllegalStateException("Unsupported style pattern '" + this.stylePattern + "'");
}
}