* 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. *
* 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
* The locale 'en_US' will always be present.
*
* @return a Set of Locales for which localization is supported
*/
public static Set
* This method provides access to locale sensitive decimal style symbols.
*
* 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.
*
* This method provides access to locale sensitive decimal style symbols.
*
* @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.
*
* 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.
*
* 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.
*
* 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.
*
* 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.
*
* 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.
*
* 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.
*
* 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.
*
* 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 + "]";
}
}