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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 org.apache.commons.lang3.time;
import java.text.DateFormat;
import java.text.Format;
import java.text.SimpleDateFormat;
import java.util.Arrays;
import java.util.Locale;
import java.util.Objects;
import java.util.TimeZone;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import org.apache.commons.lang3.LocaleUtils;
/**
* FormatCache is a cache and factory for {@link Format}s.
*
* @param The Format type.
*
* @since 3.0
*/
// TODO: Before making public move from getDateTimeInstance(Integer, ...) to int; or some other approach.
abstract class AbstractFormatCache {
/**
* Helper class to hold multipart Map keys as arrays.
*/
private static final class ArrayKey {
private static int computeHashCode(final Object[] keys) {
final int prime = 31;
int result = 1;
result = prime * result + Arrays.hashCode(keys);
return result;
}
private final Object[] keys;
private final int hashCode;
/**
* Constructs an instance of {@link MultipartKey} to hold the specified objects.
*
* @param keys the set of objects that make up the key. Each key may be null.
*/
ArrayKey(final Object... keys) {
this.keys = keys;
this.hashCode = computeHashCode(keys);
}
@Override
public boolean equals(final Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
final ArrayKey other = (ArrayKey) obj;
return Arrays.deepEquals(keys, other.keys);
}
@Override
public int hashCode() {
return hashCode;
}
}
/**
* No date or no time. Used in same parameters as DateFormat.SHORT or DateFormat.LONG
*/
static final int NONE = -1;
private static final ConcurrentMap cDateTimeInstanceCache = new ConcurrentHashMap<>(7);
/**
* Gets a date/time format for the specified styles and locale.
*
* @param dateStyle date style: FULL, LONG, MEDIUM, or SHORT, null indicates no date in format
* @param timeStyle time style: FULL, LONG, MEDIUM, or SHORT, null indicates no time in format
* @param locale The non-null locale of the desired format
* @return a localized standard date/time format
* @throws IllegalArgumentException if the Locale has no date/time pattern defined
*/
// package protected, for access from test code; do not make public or protected
static String getPatternForStyle(final Integer dateStyle, final Integer timeStyle, final Locale locale) {
final Locale safeLocale = LocaleUtils.toLocale(locale);
final ArrayKey key = new ArrayKey(dateStyle, timeStyle, safeLocale);
return cDateTimeInstanceCache.computeIfAbsent(key, k -> {
try {
final DateFormat formatter;
if (dateStyle == null) {
formatter = DateFormat.getTimeInstance(timeStyle.intValue(), safeLocale);
} else if (timeStyle == null) {
formatter = DateFormat.getDateInstance(dateStyle.intValue(), safeLocale);
} else {
formatter = DateFormat.getDateTimeInstance(dateStyle.intValue(), timeStyle.intValue(), safeLocale);
}
return ((SimpleDateFormat) formatter).toPattern();
} catch (final ClassCastException ex) {
throw new IllegalArgumentException("No date time pattern for locale: " + safeLocale);
}
});
}
private final ConcurrentMap cInstanceCache = new ConcurrentHashMap<>(7);
/**
* Create a format instance using the specified pattern, time zone
* and locale.
*
* @param pattern {@link java.text.SimpleDateFormat} compatible pattern, this will not be null.
* @param timeZone time zone, this will not be null.
* @param locale locale, this will not be null.
* @return a pattern based date/time formatter
* @throws IllegalArgumentException if pattern is invalid
* or {@code null}
*/
protected abstract F createInstance(String pattern, TimeZone timeZone, Locale locale);
/**
* Gets a date formatter instance using the specified style,
* time zone and locale.
*
* @param dateStyle date style: FULL, LONG, MEDIUM, or SHORT
* @param timeZone optional time zone, overrides time zone of
* formatted date, null means use default Locale
* @param locale optional locale, overrides system locale
* @return a localized standard date/time formatter
* @throws IllegalArgumentException if the Locale has no date/time
* pattern defined
*/
// package protected, for access from FastDateFormat; do not make public or protected
F getDateInstance(final int dateStyle, final TimeZone timeZone, final Locale locale) {
return getDateTimeInstance(Integer.valueOf(dateStyle), null, timeZone, locale);
}
/**
* Gets a date/time formatter instance using the specified style,
* time zone and locale.
*
* @param dateStyle date style: FULL, LONG, MEDIUM, or SHORT
* @param timeStyle time style: FULL, LONG, MEDIUM, or SHORT
* @param timeZone optional time zone, overrides time zone of
* formatted date, null means use default Locale
* @param locale optional locale, overrides system locale
* @return a localized standard date/time formatter
* @throws IllegalArgumentException if the Locale has no date/time
* pattern defined
*/
// package protected, for access from FastDateFormat; do not make public or protected
F getDateTimeInstance(final int dateStyle, final int timeStyle, final TimeZone timeZone, final Locale locale) {
return getDateTimeInstance(Integer.valueOf(dateStyle), Integer.valueOf(timeStyle), timeZone, locale);
}
/**
* Gets a date/time formatter instance using the specified style,
* time zone and locale.
*
* @param dateStyle date style: FULL, LONG, MEDIUM, or SHORT, null indicates no date in format
* @param timeStyle time style: FULL, LONG, MEDIUM, or SHORT, null indicates no time in format
* @param timeZone optional time zone, overrides time zone of
* formatted date, null means use default Locale
* @param locale optional locale, overrides system locale
* @return a localized standard date/time formatter
* @throws IllegalArgumentException if the Locale has no date/time
* pattern defined
*/
// This must remain private, see LANG-884
private F getDateTimeInstance(final Integer dateStyle, final Integer timeStyle, final TimeZone timeZone, Locale locale) {
locale = LocaleUtils.toLocale(locale);
final String pattern = getPatternForStyle(dateStyle, timeStyle, locale);
return getInstance(pattern, timeZone, locale);
}
/**
* Gets a formatter instance using the default pattern in the
* default time zone and locale.
*
* @return a date/time formatter
*/
public F getInstance() {
return getDateTimeInstance(DateFormat.SHORT, DateFormat.SHORT, TimeZone.getDefault(), Locale.getDefault());
}
/**
* Gets a formatter instance using the specified pattern, time zone
* and locale.
*
* @param pattern {@link java.text.SimpleDateFormat} compatible
* pattern, non-null
* @param timeZone the time zone, null means use the default TimeZone
* @param locale the locale, null means use the default Locale
* @return a pattern based date/time formatter
* @throws NullPointerException if pattern is {@code null}
* @throws IllegalArgumentException if pattern is invalid
*/
public F getInstance(final String pattern, final TimeZone timeZone, final Locale locale) {
Objects.requireNonNull(pattern, "pattern");
final TimeZone actualTimeZone = TimeZones.toTimeZone(timeZone);
final Locale actualLocale = LocaleUtils.toLocale(locale);
final ArrayKey key = new ArrayKey(pattern, actualTimeZone, actualLocale);
return cInstanceCache.computeIfAbsent(key, k -> createInstance(pattern, actualTimeZone, actualLocale));
}
/**
* Gets a time formatter instance using the specified style,
* time zone and locale.
*
* @param timeStyle time style: FULL, LONG, MEDIUM, or SHORT
* @param timeZone optional time zone, overrides time zone of
* formatted date, null means use default Locale
* @param locale optional locale, overrides system locale
* @return a localized standard date/time formatter
* @throws IllegalArgumentException if the Locale has no date/time
* pattern defined
*/
// package protected, for access from FastDateFormat; do not make public or protected
F getTimeInstance(final int timeStyle, final TimeZone timeZone, final Locale locale) {
return getDateTimeInstance(null, Integer.valueOf(timeStyle), timeZone, locale);
}
}