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/* * Copyright 2002-2017 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.util.Calendar; import java.util.Date; import org.springframework.core.convert.converter.Converter; import org.springframework.core.convert.converter.ConverterRegistry; import org.springframework.format.FormatterRegistrar; import org.springframework.format.FormatterRegistry; import org.springframework.lang.Nullable; import org.springframework.util.Assert; /** * Configures basic date formatting for use with Spring, primarily for * {@link org.springframework.format.annotation.DateTimeFormat} declarations. * Applies to fields of type {@link Date}, {@link Calendar} and {@code long}. * * <p>Designed for direct instantiation but also exposes the static * {@link #addDateConverters(ConverterRegistry)} utility method for * ad-hoc use against any {@code ConverterRegistry} instance. * * @author Phillip Webb * @since 3.2 * @see org.springframework.format.datetime.standard.DateTimeFormatterRegistrar * @see org.springframework.format.datetime.joda.JodaTimeFormatterRegistrar * @see FormatterRegistrar#registerFormatters */ public class DateFormatterRegistrar implements FormatterRegistrar { @Nullable private DateFormatter dateFormatter; /** * Set a global date formatter to register. * <p>If not specified, no general formatter for non-annotated * {@link Date} and {@link Calendar} fields will be registered. */ public void setFormatter(DateFormatter dateFormatter) { Assert.notNull(dateFormatter, "DateFormatter must not be null"); this.dateFormatter = dateFormatter; } @Override public void registerFormatters(FormatterRegistry registry) { addDateConverters(registry); registry.addFormatterForFieldAnnotation(new DateTimeFormatAnnotationFormatterFactory()); // In order to retain back compatibility we only register Date/Calendar // types when a user defined formatter is specified (see SPR-10105) if (this.dateFormatter != null) { registry.addFormatter(this.dateFormatter); registry.addFormatterForFieldType(Calendar.class, this.dateFormatter); } } /** * Add date converters to the specified registry. * @param converterRegistry the registry of converters to add to */ public static void addDateConverters(ConverterRegistry converterRegistry) { converterRegistry.addConverter(new DateToLongConverter()); converterRegistry.addConverter(new DateToCalendarConverter()); converterRegistry.addConverter(new CalendarToDateConverter()); converterRegistry.addConverter(new CalendarToLongConverter()); converterRegistry.addConverter(new LongToDateConverter()); converterRegistry.addConverter(new LongToCalendarConverter()); } private static class DateToLongConverter implements Converter<Date, Long> { @Override public Long convert(Date source) { return source.getTime(); } } private static class DateToCalendarConverter implements Converter<Date, Calendar> { @Override public Calendar convert(Date source) { Calendar calendar = Calendar.getInstance(); calendar.setTime(source); return calendar; } } private static class CalendarToDateConverter implements Converter<Calendar, Date> { @Override public Date convert(Calendar source) { return source.getTime(); } } private static class CalendarToLongConverter implements Converter<Calendar, Long> { @Override public Long convert(Calendar source) { return source.getTimeInMillis(); } } private static class LongToDateConverter implements Converter<Long, Date> { @Override public Date convert(Long source) { return new Date(source); } } private static class LongToCalendarConverter implements Converter<Long, Calendar> { @Override public Calendar convert(Long source) { Calendar calendar = Calendar.getInstance(); calendar.setTimeInMillis(source); return calendar; } } }