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/* * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ /* * This file is available under and governed by the GNU General Public * License version 2 only, as published by the Free Software Foundation. * However, the following notice accompanied the original version of this * file: * * Copyright (c) 2008-2012, Stephen Colebourne & Michael Nascimento Santos * * 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 JSR-310 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 OWNER 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 java.time.format; import java.text.DecimalFormatSymbols; import java.util.Collections; import java.util.HashSet; import java.util.Locale; import java.util.Objects; import java.util.Set; import java.util.concurrent.ConcurrentHashMap; import java.util.concurrent.ConcurrentMap; /** * Localized decimal style used in date and time formatting. * <p> * A significant part of dealing with dates and times is the localization. * This class acts as a central point for accessing the information. * * @implSpec * This class is immutable and thread-safe. * * @since 1.8 */ public final class DecimalStyle { /** * The standard set of non-localized decimal style symbols. * <p> * This uses standard ASCII characters for zero, positive, negative and a dot for the decimal point. */ public static final DecimalStyle STANDARD = new DecimalStyle('0', '+', '-', '.'); /** * The cache of DecimalStyle instances. */ private static final ConcurrentMap<Locale, DecimalStyle> CACHE = new ConcurrentHashMap<>(16, 0.75f, 2); /** * The zero digit. */ private final char zeroDigit; /** * The positive sign. */ private final char positiveSign; /** * The negative sign. */ private final char negativeSign; /** * The decimal separator. */ private final char decimalSeparator; //----------------------------------------------------------------------- /** * Lists all the locales that are supported. * <p> * The locale 'en_US' will always be present. * * @return a Set of Locales for which localization is supported */ public static Set<Locale> getAvailableLocales() { Locale[] l = DecimalFormatSymbols.getAvailableLocales(); Set<Locale> locales = new HashSet<>(l.length); Collections.addAll(locales, l); return locales; } /** * Obtains the DecimalStyle for the default * {@link java.util.Locale.Category#FORMAT FORMAT} locale. * <p> * This method provides access to locale sensitive decimal style symbols. * <p> * This is equivalent to calling * {@link #of(Locale) * of(Locale.getDefault(Locale.Category.FORMAT))}. * * @see java.util.Locale.Category#FORMAT * @return the decimal style, not null */ public static DecimalStyle ofDefaultLocale() { return of(Locale.getDefault(Locale.Category.FORMAT)); } /** * Obtains the DecimalStyle for the specified locale. * <p> * This method provides access to locale sensitive decimal style symbols. * If the locale contains "nu" (Numbering System) and/or "rg" * (Region Override) <a href="../../util/Locale.html#def_locale_extension"> * Unicode extensions</a>, returned instance will reflect the values specified with * those extensions. If both "nu" and "rg" are specified, the value from * the "nu" extension supersedes the implicit one from the "rg" extension. * * @param locale the locale, not null * @return the decimal style, not null */ public static DecimalStyle of(Locale locale) { Objects.requireNonNull(locale, "locale"); DecimalStyle info = CACHE.get(locale); if (info == null) { info = create(locale); CACHE.putIfAbsent(locale, info); info = CACHE.get(locale); } return info; } private static DecimalStyle create(Locale locale) { DecimalFormatSymbols oldSymbols = DecimalFormatSymbols.getInstance(locale); char zeroDigit = oldSymbols.getZeroDigit(); char positiveSign = '+'; char negativeSign = oldSymbols.getMinusSign(); char decimalSeparator = oldSymbols.getDecimalSeparator(); if (zeroDigit == '0' && negativeSign == '-' && decimalSeparator == '.') { return STANDARD; } return new DecimalStyle(zeroDigit, positiveSign, negativeSign, decimalSeparator); } //----------------------------------------------------------------------- /** * Restricted constructor. * * @param zeroChar the character to use for the digit of zero * @param positiveSignChar the character to use for the positive sign * @param negativeSignChar the character to use for the negative sign * @param decimalPointChar the character to use for the decimal point */ private DecimalStyle(char zeroChar, char positiveSignChar, char negativeSignChar, char decimalPointChar) { this.zeroDigit = zeroChar; this.positiveSign = positiveSignChar; this.negativeSign = negativeSignChar; this.decimalSeparator = decimalPointChar; } //----------------------------------------------------------------------- /** * Gets the character that represents zero. * <p> * The character used to represent digits may vary by culture. * This method specifies the zero character to use, which implies the characters for one to nine. * * @return the character for zero */ public char getZeroDigit() { return zeroDigit; } /** * Returns a copy of the info with a new character that represents zero. * <p> * The character used to represent digits may vary by culture. * This method specifies the zero character to use, which implies the characters for one to nine. * * @param zeroDigit the character for zero * @return a copy with a new character that represents zero, not null */ public DecimalStyle withZeroDigit(char zeroDigit) { if (zeroDigit == this.zeroDigit) { return this; } return new DecimalStyle(zeroDigit, positiveSign, negativeSign, decimalSeparator); } //----------------------------------------------------------------------- /** * Gets the character that represents the positive sign. * <p> * The character used to represent a positive number may vary by culture. * This method specifies the character to use. * * @return the character for the positive sign */ public char getPositiveSign() { return positiveSign; } /** * Returns a copy of the info with a new character that represents the positive sign. * <p> * The character used to represent a positive number may vary by culture. * This method specifies the character to use. * * @param positiveSign the character for the positive sign * @return a copy with a new character that represents the positive sign, not null */ public DecimalStyle withPositiveSign(char positiveSign) { if (positiveSign == this.positiveSign) { return this; } return new DecimalStyle(zeroDigit, positiveSign, negativeSign, decimalSeparator); } //----------------------------------------------------------------------- /** * Gets the character that represents the negative sign. * <p> * The character used to represent a negative number may vary by culture. * This method specifies the character to use. * * @return the character for the negative sign */ public char getNegativeSign() { return negativeSign; } /** * Returns a copy of the info with a new character that represents the negative sign. * <p> * The character used to represent a negative number may vary by culture. * This method specifies the character to use. * * @param negativeSign the character for the negative sign * @return a copy with a new character that represents the negative sign, not null */ public DecimalStyle withNegativeSign(char negativeSign) { if (negativeSign == this.negativeSign) { return this; } return new DecimalStyle(zeroDigit, positiveSign, negativeSign, decimalSeparator); } //----------------------------------------------------------------------- /** * Gets the character that represents the decimal point. * <p> * The character used to represent a decimal point may vary by culture. * This method specifies the character to use. * * @return the character for the decimal point */ public char getDecimalSeparator() { return decimalSeparator; } /** * Returns a copy of the info with a new character that represents the decimal point. * <p> * The character used to represent a decimal point may vary by culture. * This method specifies the character to use. * * @param decimalSeparator the character for the decimal point * @return a copy with a new character that represents the decimal point, not null */ public DecimalStyle withDecimalSeparator(char decimalSeparator) { if (decimalSeparator == this.decimalSeparator) { return this; } return new DecimalStyle(zeroDigit, positiveSign, negativeSign, decimalSeparator); } //----------------------------------------------------------------------- /** * Checks whether the character is a digit, based on the currently set zero character. * * @param ch the character to check * @return the value, 0 to 9, of the character, or -1 if not a digit */ int convertToDigit(char ch) { int val = ch - zeroDigit; return (val >= 0 && val <= 9) ? val : -1; } /** * Converts the input numeric text to the internationalized form using the zero character. * * @param numericText the text, consisting of digits 0 to 9, to convert, not null * @return the internationalized text, not null */ String convertNumberToI18N(String numericText) { if (zeroDigit == '0') { return numericText; } int diff = zeroDigit - '0'; char[] array = numericText.toCharArray(); for (int i = 0; i < array.length; i++) { array[i] = (char) (array[i] + diff); } return new String(array); } //----------------------------------------------------------------------- /** * Checks if this DecimalStyle is equal to another DecimalStyle. * * @param obj the object to check, null returns false * @return true if this is equal to the other date */ @Override public boolean equals(Object obj) { if (this == obj) { return true; } if (obj instanceof DecimalStyle) { DecimalStyle other = (DecimalStyle) obj; return (zeroDigit == other.zeroDigit && positiveSign == other.positiveSign && negativeSign == other.negativeSign && decimalSeparator == other.decimalSeparator); } return false; } /** * A hash code for this DecimalStyle. * * @return a suitable hash code */ @Override public int hashCode() { return zeroDigit + positiveSign + negativeSign + decimalSeparator; } //----------------------------------------------------------------------- /** * Returns a string describing this DecimalStyle. * * @return a string description, not null */ @Override public String toString() { return "DecimalStyle[" + zeroDigit + positiveSign + negativeSign + decimalSeparator + "]"; } }