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/*
* Copyright 2008 Google Inc.
*
* 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
*
* 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 com.google.gwt.i18n.client;
import com.google.gwt.core.client.GWT;
import com.google.gwt.i18n.client.constants.NumberConstants;
/**
* Formats and parses numbers using locale-sensitive patterns.
*
* This class provides comprehensive and flexible support for a wide variety of
* localized formats, including
* <ul>
* <li><b>Locale-specific symbols</b> such as decimal point, group separator,
* digit representation, currency symbol, percent, and permill</li>
* <li><b>Numeric variations</b> including integers ("123"), fixed-point
* numbers ("123.4"), scientific notation ("1.23E4"), percentages ("12%"), and
* currency amounts ("$123")</li>
* <li><b>Predefined standard patterns</b> that can be used both for parsing
* and formatting, including {@link #getDecimalFormat() decimal},
* {@link #getCurrencyFormat() currency},
* {@link #getPercentFormat() percentages}, and
* {@link #getScientificFormat() scientific}</li>
* <li><b>Custom patterns</b> and supporting features designed to make it
* possible to parse and format numbers in any locale, including support for
* Western, Arabic, and Indic digits</li>
* </ul>
*
* <h3>Patterns</h3>
* <p>
* Formatting and parsing are based on customizable patterns that can include a
* combination of literal characters and special characters that act as
* placeholders and are replaced by their localized counterparts. Many
* characters in a pattern are taken literally; they are matched during parsing
* and output unchanged during formatting. Special characters, on the other
* hand, stand for other characters, strings, or classes of characters. For
* example, the '<code>#</code>' character is replaced by a localized digit.
* </p>
*
* <p>
* Often the replacement character is the same as the pattern character. In the
* U.S. locale, for example, the '<code>,</code>' grouping character is
* replaced by the same character '<code>,</code>'. However, the replacement
* is still actually happening, and in a different locale, the grouping
* character may change to a different character, such as '<code>.</code>'.
* Some special characters affect the behavior of the formatter by their
* presence. For example, if the percent character is seen, then the value is
* multiplied by 100 before being displayed.
* </p>
*
* <p>
* The characters listed below are used in patterns. Localized symbols use the
* corresponding characters taken from corresponding locale symbol collection,
* which can be found in the properties files residing in the
* <code><nobr>com.google.gwt.i18n.client.constants</nobr></code>. To insert
* a special character in a pattern as a literal (that is, without any special
* meaning) the character must be quoted. There are some exceptions to this
* which are noted below.
* </p>
*
* <table>
* <tr>
* <th>Symbol</th>
* <th>Location</th>
* <th>Localized?</th>
* <th>Meaning</th>
* </tr>
*
* <tr>
* <td><code>0</code></td>
* <td>Number</td>
* <td>Yes</td>
* <td>Digit</td>
* </tr>
*
* <tr>
* <td><code>#</code></td>
* <td>Number</td>
* <td>Yes</td>
* <td>Digit, zero shows as absent</td>
* </tr>
*
* <tr>
* <td><code>.</code></td>
* <td>Number</td>
* <td>Yes</td>
* <td>Decimal separator or monetary decimal separator</td>
* </tr>
*
* <tr>
* <td><code>-</code></td>
* <td>Number</td>
* <td>Yes</td>
* <td>Minus sign</td>
* </tr>
*
* <tr>
* <td><code>,</code></td>
* <td>Number</td>
* <td>Yes</td>
* <td>Grouping separator</td>
* </tr>
*
* <tr>
* <td><code>E</code></td>
* <td>Number</td>
* <td>Yes</td>
* <td>Separates mantissa and exponent in scientific notation; need not be
* quoted in prefix or suffix</td>
* </tr>
*
* <tr>
* <td><code>;</code></td>
* <td>Subpattern boundary</td>
* <td>Yes</td>
* <td>Separates positive and negative subpatterns</td>
* </tr>
*
* <tr>
* <td><code>%</code></td>
* <td>Prefix or suffix</td>
* <td>Yes</td>
* <td>Multiply by 100 and show as percentage</td>
* </tr>
*
* <tr>
* <td><nobr><code>\u2030</code> (\u005Cu2030)</nobr></td>
* <td>Prefix or suffix</td>
* <td>Yes</td>
* <td>Multiply by 1000 and show as per mille</td>
* </tr>
*
* <tr>
* <td><nobr><code>\u00A4</code> (\u005Cu00A4)</nobr></td>
* <td>Prefix or suffix</td>
* <td>No</td>
* <td>Currency sign, replaced by currency symbol; if doubled, replaced by
* international currency symbol; if present in a pattern, the monetary decimal
* separator is used instead of the decimal separator</td>
* </tr>
*
* <tr>
* <td><code>'</code></td>
* <td>Prefix or suffix</td>
* <td>No</td>
* <td>Used to quote special characters in a prefix or suffix; for example,
* <code>"'#'#"</code> formats <code>123</code> to <code>"#123"</code>;
* to create a single quote itself, use two in succession, such as
* <code>"# o''clock"</code></td>
* </tr>
*
* </table>
*
* <p>
* A <code>NumberFormat</code> pattern contains a postive and negative
* subpattern separated by a semicolon, such as
* <code>"#,##0.00;(#,##0.00)"</code>. Each subpattern has a prefix, a
* numeric part, and a suffix. If there is no explicit negative subpattern, the
* negative subpattern is the localized minus sign prefixed to the positive
* subpattern. That is, <code>"0.00"</code> alone is equivalent to
* <code>"0.00;-0.00"</code>. If there is an explicit negative subpattern, it
* serves only to specify the negative prefix and suffix; the number of digits,
* minimal digits, and other characteristics are ignored in the negative
* subpattern. That means that <code>"#,##0.0#;(#)"</code> has precisely the
* same result as <code>"#,##0.0#;(#,##0.0#)"</code>.
* </p>
*
* <p>
* The prefixes, suffixes, and various symbols used for infinity, digits,
* thousands separators, decimal separators, etc. may be set to arbitrary
* values, and they will appear properly during formatting. However, care must
* be taken that the symbols and strings do not conflict, or parsing will be
* unreliable. For example, the decimal separator and thousands separator should
* be distinct characters, or parsing will be impossible.
* </p>
*
* <p>
* The grouping separator is a character that separates clusters of integer
* digits to make large numbers more legible. It commonly used for thousands,
* but in some locales it separates ten-thousands. The grouping size is the
* number of digits between the grouping separators, such as 3 for "100,000,000"
* or 4 for "1 0000 0000".
* </p>
*
* <h3>Pattern Grammar (BNF)</h3>
* <p>
* The pattern itself uses the following grammar:
* </p>
*
* <table>
* <tr>
* <td>pattern</td>
* <td>:=</td>
* <td style="white-space: nowrap">subpattern ('<code>;</code>'
* subpattern)?</td>
* </tr>
* <tr>
* <td>subpattern</td>
* <td>:=</td>
* <td>prefix? number exponent? suffix?</td>
* </tr>
* <tr>
* <td>number</td>
* <td>:=</td>
* <td style="white-space: nowrap">(integer ('<code>.</code>' fraction)?) |
* sigDigits</td>
* </tr>
* <tr>
* <td>prefix</td>
* <td>:=</td>
* <td style="white-space: nowrap">'<code>\u005Cu0000</code>'..'<code>\u005CuFFFD</code>' -
* specialCharacters</td>
* </tr>
* <tr>
* <td>suffix</td>
* <td>:=</td>
* <td style="white-space: nowrap">'<code>\u005Cu0000</code>'..'<code>\u005CuFFFD</code>' -
* specialCharacters</td>
* </tr>
* <tr>
* <td>integer</td>
* <td>:=</td>
* <td style="white-space: nowrap">'<code>#</code>'* '<code>0</code>'*'<code>0</code>'</td>
* </tr>
* <tr>
* <td>fraction</td>
* <td>:=</td>
* <td style="white-space: nowrap">'<code>0</code>'* '<code>#</code>'*</td>
* </tr>
* <tr>
* <td>sigDigits</td>
* <td>:=</td>
* <td style="white-space: nowrap">'<code>#</code>'* '<code>@</code>''<code>@</code>'* '<code>#</code>'*</td>
* </tr>
* <tr>
* <td>exponent</td>
* <td>:=</td>
* <td style="white-space: nowrap">'<code>E</code>' '<code>+</code>'? '<code>0</code>'* '<code>0</code>'</td>
* </tr>
* <tr>
* <td>padSpec</td>
* <td>:=</td>
* <td style="white-space: nowrap">'<code>*</code>' padChar</td>
* </tr>
* <tr>
* <td>padChar</td>
* <td>:=</td>
* <td>'<code>\u005Cu0000</code>'..'<code>\u005CuFFFD</code>' - quote</td>
* </tr>
* </table>
*
* <p>
* Notation:
* </p>
*
* <table>
* <tr>
* <td>X*</td>
* <td style="white-space: nowrap">0 or more instances of X</td>
* </tr>
*
* <tr>
* <td>X?</td>
* <td style="white-space: nowrap">0 or 1 instances of X</td>
* </tr>
*
* <tr>
* <td>X|Y</td>
* <td style="white-space: nowrap">either X or Y</td>
* </tr>
*
* <tr>
* <td>C..D</td>
* <td style="white-space: nowrap">any character from C up to D, inclusive</td>
* </tr>
*
* <tr>
* <td>S-T</td>
* <td style="white-space: nowrap">characters in S, except those in T</td>
* </tr>
* </table>
*
* <p>
* The first subpattern is for positive numbers. The second (optional)
* subpattern is for negative numbers.
* </p>
*
* <h3>Example</h3> {@example com.google.gwt.examples.NumberFormatExample}
*
*
*/
public class NumberFormat {
// Sets of constants as defined for the current locale from CLDR.
protected static final NumberConstants localizedNumberConstants = LocaleInfo.getCurrentLocale().getNumberConstants();
/**
* Current NumberConstants interface to use, see
* {@link #setForcedLatinDigits(boolean)} for changing it.
*/
protected static NumberConstants defaultNumberConstants = localizedNumberConstants;
// Cached instances of standard formatters.
private static NumberFormat cachedCurrencyFormat;
private static NumberFormat cachedDecimalFormat;
private static NumberFormat cachedPercentFormat;
private static NumberFormat cachedScientificFormat;
// Number constants mapped to use latin digits/separators.
private static NumberConstants latinNumberConstants = null;
// Localized characters for dot and comma in number patterns, used to produce
// the latin mapping for arbitrary locales. Any separator not in either of
// these strings will be mapped to non-breaking space (U+00A0).
private static final String LOCALIZED_COMMA_EQUIVALENTS = ",\u060C\u066B\u3001\uFE10\uFE11\uFE50\uFE51\uFF0C\uFF64";
private static final String LOCALIZED_DOT_EQUIVALENTS = ".\u2024\u3002\uFE12\uFE52\uFF0E\uFF61";
// Constants for characters used in programmatic (unlocalized) patterns.
private static final char CURRENCY_SIGN = '\u00A4';
private static final char PATTERN_DECIMAL_SEPARATOR = '.';
private static final char PATTERN_DIGIT = '#';
private static final char PATTERN_EXPONENT = 'E';
private static final char PATTERN_GROUPING_SEPARATOR = ',';
private static final char PATTERN_MINUS = '-';
private static final char PATTERN_PER_MILLE = '\u2030';
private static final char PATTERN_PERCENT = '%';
private static final char PATTERN_SEPARATOR = ';';
private static final char PATTERN_ZERO_DIGIT = '0';
private static final char QUOTE = '\'';
/**
* @return true if all new NumberFormat instances will use latin digits
* and related characters rather than the localized ones.
*/
public static boolean forcedLatinDigits() {
return defaultNumberConstants != localizedNumberConstants;
}
/**
* Provides the standard currency format for the default locale.
*
* @return a <code>NumberFormat</code> capable of producing and consuming
* currency format for the default locale
*/
public static NumberFormat getCurrencyFormat() {
if (cachedCurrencyFormat == null) {
cachedCurrencyFormat = new NumberFormat(
defaultNumberConstants.currencyPattern(), CurrencyList.get().getDefault(), false);
}
return cachedCurrencyFormat;
}
/**
* Provides the standard currency format for the default locale using a
* specified currency.
*
* @param currencyData currency data to use
* @return a <code>NumberFormat</code> capable of producing and consuming
* currency format for the default locale
*/
public static NumberFormat getCurrencyFormat(CurrencyData currencyData) {
return new NumberFormat(defaultNumberConstants.currencyPattern(),
currencyData, false);
}
/**
* Provides the standard currency format for the default locale using a
* specified currency.
*
* @param currencyCode valid currency code, as defined in
* com.google.gwt.i18n.client.constants.CurrencyCodeMapConstants.properties
* @return a <code>NumberFormat</code> capable of producing and consuming
* currency format for the default locale
* @throws IllegalArgumentException if the currency code is unknown
*/
public static NumberFormat getCurrencyFormat(String currencyCode) {
// TODO(jat): consider caching values per currency code.
return new NumberFormat(defaultNumberConstants.currencyPattern(),
lookupCurrency(currencyCode), false);
}
/**
* Provides the standard decimal format for the default locale.
*
* @return a <code>NumberFormat</code> capable of producing and consuming
* decimal format for the default locale
*/
public static NumberFormat getDecimalFormat() {
if (cachedDecimalFormat == null) {
cachedDecimalFormat = new NumberFormat(
defaultNumberConstants.decimalPattern(),
CurrencyList.get().getDefault(), false);
}
return cachedDecimalFormat;
}
/**
* Gets a <code>NumberFormat</code> instance for the default locale using
* the specified pattern and the default currencyCode.
*
* @param pattern pattern for this formatter
* @return a NumberFormat instance
* @throws IllegalArgumentException if the specified pattern is invalid
*/
public static NumberFormat getFormat(String pattern) {
return new NumberFormat(pattern, CurrencyList.get().getDefault(), true);
}
/**
* Gets a custom <code>NumberFormat</code> instance for the default locale
* using the specified pattern and currency code.
*
* @param pattern pattern for this formatter
* @param currencyData currency data
* @return a NumberFormat instance
* @throws IllegalArgumentException if the specified pattern is invalid
*/
public static NumberFormat getFormat(String pattern,
CurrencyData currencyData) {
return new NumberFormat(pattern, currencyData, true);
}
/**
* Gets a custom <code>NumberFormat</code> instance for the default locale
* using the specified pattern and currency code.
*
* @param pattern pattern for this formatter
* @param currencyCode international currency code
* @return a NumberFormat instance
* @throws IllegalArgumentException if the specified pattern is invalid
* or the currency code is unknown
*/
public static NumberFormat getFormat(String pattern, String currencyCode) {
return new NumberFormat(pattern, lookupCurrency(currencyCode), true);
}
/**
* Provides the standard percent format for the default locale.
*
* @return a <code>NumberFormat</code> capable of producing and consuming
* percent format for the default locale
*/
public static NumberFormat getPercentFormat() {
if (cachedPercentFormat == null) {
cachedPercentFormat = new NumberFormat(
defaultNumberConstants.percentPattern(),
CurrencyList.get().getDefault(), false);
}
return cachedPercentFormat;
}
/**
* Provides the standard scientific format for the default locale.
*
* @return a <code>NumberFormat</code> capable of producing and consuming
* scientific format for the default locale
*/
public static NumberFormat getScientificFormat() {
if (cachedScientificFormat == null) {
cachedScientificFormat = new NumberFormat(
defaultNumberConstants.scientificPattern(),
CurrencyList.get().getDefault(), false);
}
return cachedScientificFormat;
}
/**
* Specify whether all new NumberFormat instances will use latin digits
* and related characters rather than the localized ones.
*
* @param useLatinDigits true if latin digits/etc should be used, false if
* localized digits/etc should be used.
*/
public static void setForcedLatinDigits(boolean useLatinDigits) {
// Invalidate cached formats if changing
if (useLatinDigits != forcedLatinDigits()) {
cachedCurrencyFormat = null;
cachedDecimalFormat = null;
cachedPercentFormat = null;
cachedScientificFormat = null;
}
if (useLatinDigits) {
if (latinNumberConstants == null) {
latinNumberConstants = createLatinNumberConstants(
localizedNumberConstants);
}
defaultNumberConstants = latinNumberConstants;
} else {
defaultNumberConstants = localizedNumberConstants;
}
}
/**
* Create a delocalized NumberConstants instance from a localized one.
*
* @param orig localized NumberConstants instance
* @return NumberConstants instance using latin digits/etc
*/
protected static NumberConstants createLatinNumberConstants(
final NumberConstants orig) {
final String groupingSeparator = remapSeparator(
orig.groupingSeparator());
final String decimalSeparator = remapSeparator(
orig.decimalSeparator());
final String monetaryGroupingSeparator = remapSeparator(
orig.monetaryGroupingSeparator());
final String monetarySeparator = remapSeparator(
orig.monetarySeparator());
return new NumberConstants() {
public String currencyPattern() {
return orig.currencyPattern();
}
public String decimalPattern() {
return orig.decimalPattern();
}
public String decimalSeparator() {
return decimalSeparator;
}
public String defCurrencyCode() {
return orig.defCurrencyCode();
}
public String exponentialSymbol() {
return orig.exponentialSymbol();
}
public String groupingSeparator() {
return groupingSeparator;
}
public String infinity() {
return orig.infinity();
}
public String minusSign() {
return orig.minusSign();
}
public String monetaryGroupingSeparator() {
return monetaryGroupingSeparator;
}
public String monetarySeparator() {
return monetarySeparator;
}
public String notANumber() {
return orig.notANumber();
}
public String percent() {
return orig.percent();
}
public String percentPattern() {
return orig.percentPattern();
}
public String perMill() {
return orig.perMill();
}
public String plusSign() {
return orig.plusSign();
}
public String scientificPattern() {
return orig.scientificPattern();
}
public String zeroDigit() {
return "0";
}
};
}
/**
* Remap a localized separator to an equivalent latin one.
*
* @param separator
* @return delocalized separator character
*/
protected static String remapSeparator(String separator) {
char ch = separator.length() > 0 ? separator.charAt(0) : 0xFFFF;
if (LOCALIZED_DOT_EQUIVALENTS.indexOf(ch) >= 0) {
return ".";
}
if (LOCALIZED_COMMA_EQUIVALENTS.indexOf(ch) >= 0) {
return ",";
}
return "\u00A0";
}
/**
* Lookup a currency code.
*
* @param currencyCode ISO4217 currency code
* @return a CurrencyData instance
* @throws IllegalArgumentException if the currency code is unknown
*/
private static CurrencyData lookupCurrency(String currencyCode) {
CurrencyData currencyData = CurrencyList.get().lookup(currencyCode);
if (currencyData == null) {
throw new IllegalArgumentException("Currency code " + currencyCode
+ " is unkown in locale "
+ LocaleInfo.getCurrentLocale().getLocaleName());
}
return currencyData;
}
private static native String toFixed(double d, int digits) /*-{
return d.toFixed(digits);
}-*/;
// The currency code.
private final String currencyCode;
// Currency setting.
private final String currencySymbol;
// Forces the decimal separator to always appear in a formatted number.
private boolean decimalSeparatorAlwaysShown = false;
// The number of digits between grouping separators in the integer
// portion of a number.
private int groupingSize = 3;
private boolean isCurrencyFormat = false;
private int maximumFractionDigits = 3; // invariant, >= minFractionDigits.
private int maximumIntegerDigits = 40;
private int minExponentDigits;
private int minimumFractionDigits = 0;
private int minimumIntegerDigits = 1;
// The multiplier for use in percent, per mille, etc.
private int multiplier = 1;
private String negativePrefix = "-";
private String negativeSuffix = "";
// Locale specific symbol collection.
private final NumberConstants numberConstants;
// The pattern to use for formatting and parsing.
private final String pattern;
private String positivePrefix = "";
private String positiveSuffix = "";
// True to force the use of exponential (i.e. scientific) notation.
private boolean useExponentialNotation = false;
/**
* Constructs a format object based on the specified settings.
*
* @param numberConstants the locale-specific number constants to use for this
* format -- **NOTE** subclasses passing their own instance here
* should pay attention to {@link #forcedLatinDigits()} and remap
* localized symbols using
* {@link #createLatinNumberConstants(NumberConstants)}
* @param pattern pattern that specify how number should be formatted
* @param cdata currency data that should be used
* @param userSuppliedPattern true if the pattern was supplied by the user
*/
protected NumberFormat(NumberConstants numberConstants, String pattern, CurrencyData cdata,
boolean userSuppliedPattern) {
if (cdata == null) {
throw new IllegalArgumentException("Unknown currency code");
}
this.numberConstants = numberConstants;
this.pattern = pattern;
currencyCode = cdata.getCurrencyCode();
currencySymbol = cdata.getCurrencySymbol();
// TODO: handle per-currency flags, such as symbol prefix/suffix and spacing
parsePattern(this.pattern);
if (!userSuppliedPattern && isCurrencyFormat) {
minimumFractionDigits = cdata.getDefaultFractionDigits();
maximumFractionDigits = minimumFractionDigits;
}
}
/**
* Constructs a format object for the default locale based on the specified
* settings.
*
* @param pattern pattern that specify how number should be formatted
* @param cdata currency data that should be used
* @param userSuppliedPattern true if the pattern was supplied by the user
*/
protected NumberFormat(String pattern, CurrencyData cdata, boolean userSuppliedPattern) {
this(defaultNumberConstants, pattern, cdata, userSuppliedPattern);
}
/**
* This method formats a double to produce a string.
*
* @param number The double to format
* @return the formatted number string
*/
public String format(double number) {
StringBuffer result = new StringBuffer();
if (Double.isNaN(number)) {
result.append(numberConstants.notANumber());
return result.toString();
}
boolean isNegative = ((number < 0.0) || (number == 0.0 && 1 / number < 0.0));
result.append(isNegative ? negativePrefix : positivePrefix);
if (Double.isInfinite(number)) {
result.append(numberConstants.infinity());
} else {
if (isNegative) {
number = -number;
}
number *= multiplier;
if (useExponentialNotation) {
subformatExponential(number, result);
} else {
subformatFixed(number, result, minimumIntegerDigits);
}
}
result.append(isNegative ? negativeSuffix : positiveSuffix);
return result.toString();
}
/**
* Returns the pattern used by this number format.
*/
public String getPattern() {
return pattern;
}
/**
* Parses text to produce a numeric value. A {@link NumberFormatException} is
* thrown if either the text is empty or if the parse does not consume all
* characters of the text.
*
* @param text the string being parsed
* @return a parsed number value
* @throws NumberFormatException if the entire text could not be converted
* into a number
*/
public double parse(String text) throws NumberFormatException {
int[] pos = {0};
double result = parse(text, pos);
if (pos[0] == 0 || pos[0] != text.length()) {
throw new NumberFormatException(text);
}
return result;
}
/**
* Parses text to produce a numeric value.
*
* <p>
* The method attempts to parse text starting at the index given by pos. If
* parsing succeeds, then the index of <code>pos</code> is updated to the
* index after the last character used (parsing does not necessarily use all
* characters up to the end of the string), and the parsed number is returned.
* The updated <code>pos</code> can be used to indicate the starting point
* for the next call to this method. If an error occurs, then the index of
* <code>pos</code> is not changed.
* </p>
*
* @param text the string to be parsed
* @param inOutPos position to pass in and get back
* @return a double value representing the parsed number, or <code>0.0</code>
* if the parse fails
* @throws NumberFormatException if the text segment could not be converted into a number
*/
public double parse(String text, int[] inOutPos) throws NumberFormatException {
double ret = 0.0;
boolean gotPositivePrefix = text.startsWith(positivePrefix, inOutPos[0]);
boolean gotNegativePrefix = text.startsWith(negativePrefix, inOutPos[0]);
boolean gotPositiveSuffix = text.endsWith(positiveSuffix);
boolean gotNegativeSuffix = text.endsWith(negativeSuffix);
boolean gotPositive = gotPositivePrefix && gotPositiveSuffix;
boolean gotNegative = gotNegativePrefix && gotNegativeSuffix;
// Handle conflicts where we get both patterns, which usually
// happens when one is a prefix of the other (such as the positive
// pattern having empty prefix/suffixes).
if (gotPositive && gotNegative) {
if (positivePrefix.length() > negativePrefix.length()) {
gotNegative = false;
} else if (positivePrefix.length() < negativePrefix.length()) {
gotPositive = false;
} else if (positiveSuffix.length() > negativeSuffix.length()) {
gotNegative = false;
} else if (positiveSuffix.length() < negativeSuffix.length()) {
gotPositive = false;
} else {
// can't tell patterns apart, must be positive
gotNegative = false;
}
} else if (!gotPositive && !gotNegative) {
throw new NumberFormatException(text
+ " does not have either positive or negative affixes");
}
// Contains just the value to parse, stripping any prefix or suffix
String valueOnly = null;
if (gotPositive) {
inOutPos[0] += positivePrefix.length();
valueOnly = text.substring(inOutPos[0],
text.length() - positiveSuffix.length());
} else {
inOutPos[0] += negativePrefix.length();
valueOnly = text.substring(inOutPos[0],
text.length() - negativeSuffix.length());
}
// Process digits or special values, and find decimal position.
if (valueOnly.equals(numberConstants.infinity())) {
inOutPos[0] += numberConstants.infinity().length();
ret = Double.POSITIVE_INFINITY;
} else if (valueOnly.equals(numberConstants.notANumber())) {
inOutPos[0] += numberConstants.notANumber().length();
ret = Double.NaN;
} else {
int[] tempPos = {0};
ret = parseNumber(valueOnly, tempPos);
inOutPos[0] += tempPos[0];
}
// Check for suffix.
if (gotPositive) {
inOutPos[0] += positiveSuffix.length();
} else if (gotNegative) {
inOutPos[0] += negativeSuffix.length();
}
if (gotNegative) {
ret = -ret;
}
return ret;
}
protected int getGroupingSize() {
return groupingSize;
}
protected String getNegativePrefix() {
return negativePrefix;
}
protected String getNegativeSuffix() {
return negativeSuffix;
}
protected NumberConstants getNumberConstants() {
return numberConstants;
}
protected String getPositivePrefix() {
return positivePrefix;
}
protected String getPositiveSuffix() {
return positiveSuffix;
}
protected boolean isDecimalSeparatorAlwaysShown() {
return decimalSeparatorAlwaysShown;
}
/**
* This method formats the exponent part of a double.
*
* @param exponent exponential value
* @param result formatted exponential part will be append to it
*/
private void addExponentPart(int exponent, StringBuffer result) {
result.append(numberConstants.exponentialSymbol());
if (exponent < 0) {
exponent = -exponent;
result.append(numberConstants.minusSign());
}
String exponentDigits = String.valueOf(exponent);
int len = exponentDigits.length();
for (int i = len; i < minExponentDigits; ++i) {
result.append(numberConstants.zeroDigit());
}
int zeroDelta = numberConstants.zeroDigit().charAt(0) - '0';
for (int i = 0; i < len; ++i) {
result.append((char) (exponentDigits.charAt(i) + zeroDelta));
}
}
/**
* This method return the digit that represented by current character, it
* could be either '0' to '9', or a locale specific digit.
*
* @param ch character that represents a digit
* @return the digit value
*/
private int getDigit(char ch) {
if ('0' <= ch && ch <= '0' + 9) {
return (ch - '0');
} else {
char zeroChar = numberConstants.zeroDigit().charAt(0);
return ((zeroChar <= ch && ch <= zeroChar + 9) ? (ch - zeroChar) : -1);
}
}
/**
* This does the work of String.valueOf(long), but given a double as input
* and avoiding our emulated longs. Contrasted with String.valueOf(double),
* it ensures (a) there will be no trailing .0, and (b) unwinds E-notation.
*
* @param number the integral value to convert
* @return the string representing that integer
*/
private String makeIntString(double number) {
String intPart = String.valueOf(number);
if (GWT.isScript()) {
return intPart; // JavaScript does the right thing for integral doubles
}
// ...but bytecode (hosted mode) does not... String.valueOf(double) will
// either end in .0 (non internationalized) which we don't want but is
// easy, or, for large numbers, it will be E-notation, which is annoying.
int digitLen = intPart.length();
if (intPart.charAt(digitLen - 2) == '.') {
return intPart.substring(0, digitLen - 2);
}
// if we have E notation, (1) the exponent will be positive (else
// intValue is 0, which doesn't need E notation), and (2) there will
// be a radix dot (String.valueOf() isn't interationalized)
int radix = intPart.indexOf('.');
int exp = intPart.indexOf('E');
int digits = 0;
for (int i = exp + 1; i < intPart.length(); i++) {
digits = digits * 10 + (intPart.charAt(i) - '0');
}
digits++; // exp of zero is one int digit...
StringBuffer newIntPart = new StringBuffer();
newIntPart.append(intPart.substring(0, radix));
newIntPart.append(intPart.substring(radix + 1, exp));
while (newIntPart.length() < digits) {
newIntPart.append('0');
}
newIntPart.setLength(digits);
return newIntPart.toString();
}
/**
* This method parses affix part of pattern.
*
* @param pattern pattern string that need to be parsed
* @param start start position to parse
* @param affix store the parsed result
* @param inNegativePattern true if we are parsing the negative pattern and
* therefore only care about the prefix and suffix
* @return how many characters parsed
*/
private int parseAffix(String pattern, int start, StringBuffer affix,
boolean inNegativePattern) {
affix.delete(0, affix.length());
boolean inQuote = false;
int len = pattern.length();
for (int pos = start; pos < len; ++pos) {
char ch = pattern.charAt(pos);
if (ch == QUOTE) {
if ((pos + 1) < len && pattern.charAt(pos + 1) == QUOTE) {
++pos;
affix.append("'"); // 'don''t'
} else {
inQuote = !inQuote;
}
continue;
}
if (inQuote) {
affix.append(ch);
} else {
switch (ch) {
case PATTERN_DIGIT:
case PATTERN_ZERO_DIGIT:
case PATTERN_GROUPING_SEPARATOR:
case PATTERN_DECIMAL_SEPARATOR:
case PATTERN_SEPARATOR:
return pos - start;
case CURRENCY_SIGN:
isCurrencyFormat = true;
if ((pos + 1) < len && pattern.charAt(pos + 1) == CURRENCY_SIGN) {
++pos;
affix.append(currencyCode);
} else {
affix.append(currencySymbol);
}
break;
case PATTERN_PERCENT:
if (!inNegativePattern) {
if (multiplier != 1) {
throw new IllegalArgumentException(
"Too many percent/per mille characters in pattern \""
+ pattern + '"');
}
multiplier = 100;
}
affix.append(numberConstants.percent());
break;
case PATTERN_PER_MILLE:
if (!inNegativePattern) {
if (multiplier != 1) {
throw new IllegalArgumentException(
"Too many percent/per mille characters in pattern \""
+ pattern + '"');
}
multiplier = 1000;
}
affix.append(numberConstants.perMill());
break;
case PATTERN_MINUS:
affix.append("-");
break;
default:
affix.append(ch);
}
}
}
return len - start;
}
/**
* This function parses a "localized" text into a <code>double</code>. It
* needs to handle locale specific decimal, grouping, exponent and digit.
*
* @param text the text that need to be parsed
* @param pos in/out parsing position. in case of failure, this shouldn't be
* changed
* @return double value, could be 0.0 if nothing can be parsed
*/
private double parseNumber(String text, int[] pos) {
double ret;
boolean sawDecimal = false;
boolean sawExponent = false;
boolean sawDigit = false;
int scale = 1;
String decimal = isCurrencyFormat ? numberConstants.monetarySeparator()
: numberConstants.decimalSeparator();
String grouping = isCurrencyFormat
? numberConstants.monetaryGroupingSeparator()
: numberConstants.groupingSeparator();
String exponentChar = numberConstants.exponentialSymbol();
StringBuffer normalizedText = new StringBuffer();
for (; pos[0] < text.length(); ++pos[0]) {
char ch = text.charAt(pos[0]);
int digit = getDigit(ch);
if (digit >= 0 && digit <= 9) {
normalizedText.append((char) (digit + '0'));
sawDigit = true;
} else if (ch == decimal.charAt(0)) {
if (sawDecimal || sawExponent) {
break;
}
normalizedText.append('.');
sawDecimal = true;
} else if (ch == grouping.charAt(0)) {
if (sawDecimal || sawExponent) {
break;
}
continue;
} else if (ch == exponentChar.charAt(0)) {
if (sawExponent) {
break;
}
normalizedText.append('E');
sawExponent = true;
} else if (ch == '+' || ch == '-') {
normalizedText.append(ch);
} else if (ch == numberConstants.percent().charAt(0)) {
if (scale != 1) {
break;
}
scale = 100;
if (sawDigit) {
++pos[0];
break;
}
} else if (ch == numberConstants.perMill().charAt(0)) {
if (scale != 1) {
break;
}
scale = 1000;
if (sawDigit) {
++pos[0];
break;
}
} else {
break;
}
}
// parseDouble could throw NumberFormatException, rethrow with correct text.
try {
ret = Double.parseDouble(normalizedText.toString());
} catch (NumberFormatException e) {
throw new NumberFormatException(text);
}
ret = ret / scale;
return ret;
}
/**
* Method parses provided pattern, result is stored in member variables.
*
* @param pattern
*/
private void parsePattern(String pattern) {
int pos = 0;
StringBuffer affix = new StringBuffer();
pos += parseAffix(pattern, pos, affix, false);
positivePrefix = affix.toString();
pos += parseTrunk(pattern, pos, false);
pos += parseAffix(pattern, pos, affix, false);
positiveSuffix = affix.toString();
if (pos < pattern.length() && pattern.charAt(pos) == PATTERN_SEPARATOR) {
++pos;
pos += parseAffix(pattern, pos, affix, true);
negativePrefix = affix.toString();
// the negative pattern is only used for prefix/suffix
pos += parseTrunk(pattern, pos, true);
pos += parseAffix(pattern, pos, affix, true);
negativeSuffix = affix.toString();
} else {
negativePrefix = numberConstants.minusSign() + positivePrefix;
negativeSuffix = positiveSuffix;
}
}
/**
* This method parses the trunk part of a pattern.
*
* @param pattern pattern string that need to be parsed
* @param start where parse started
* @param ignorePattern true if we are only parsing this for length
* and correctness, such as in the negative portion of the pattern
* @return how many characters parsed
*/
private int parseTrunk(String pattern, int start, boolean ignorePattern) {
int decimalPos = -1;
int digitLeftCount = 0, zeroDigitCount = 0, digitRightCount = 0;
byte groupingCount = -1;
int len = pattern.length();
int pos = start;
boolean loop = true;
for (; (pos < len) && loop; ++pos) {
char ch = pattern.charAt(pos);
switch (ch) {
case PATTERN_DIGIT:
if (zeroDigitCount > 0) {
++digitRightCount;
} else {
++digitLeftCount;
}
if (groupingCount >= 0 && decimalPos < 0) {
++groupingCount;
}
break;
case PATTERN_ZERO_DIGIT:
if (digitRightCount > 0) {
throw new IllegalArgumentException("Unexpected '0' in pattern \""
+ pattern + '"');
}
++zeroDigitCount;
if (groupingCount >= 0 && decimalPos < 0) {
++groupingCount;
}
break;
case PATTERN_GROUPING_SEPARATOR:
groupingCount = 0;
break;
case PATTERN_DECIMAL_SEPARATOR:
if (decimalPos >= 0) {
throw new IllegalArgumentException(
"Multiple decimal separators in pattern \"" + pattern + '"');
}
decimalPos = digitLeftCount + zeroDigitCount + digitRightCount;
break;
case PATTERN_EXPONENT:
if (!ignorePattern) {
if (useExponentialNotation) {
throw new IllegalArgumentException("Multiple exponential "
+ "symbols in pattern \"" + pattern + '"');
}
useExponentialNotation = true;
minExponentDigits = 0;
}
// Use lookahead to parse out the exponential part
// of the pattern, then jump into phase 2.
while ((pos + 1) < len
&& pattern.charAt(pos + 1) == PATTERN_ZERO_DIGIT) {
++pos;
if (!ignorePattern) {
++minExponentDigits;
}
}
if (!ignorePattern && (digitLeftCount + zeroDigitCount) < 1
|| minExponentDigits < 1) {
throw new IllegalArgumentException("Malformed exponential "
+ "pattern \"" + pattern + '"');
}
loop = false;
break;
default:
--pos;
loop = false;
break;
}
}
if (zeroDigitCount == 0 && digitLeftCount > 0 && decimalPos >= 0) {
// Handle "###.###" and "###." and ".###".
int n = decimalPos;
if (n == 0) { // Handle ".###"
++n;
}
digitRightCount = digitLeftCount - n;
digitLeftCount = n - 1;
zeroDigitCount = 1;
}
// Do syntax checking on the digits.
if ((decimalPos < 0 && digitRightCount > 0)
|| (decimalPos >= 0 && (decimalPos < digitLeftCount || decimalPos > (digitLeftCount + zeroDigitCount)))
|| groupingCount == 0) {
throw new IllegalArgumentException("Malformed pattern \"" + pattern + '"');
}
if (ignorePattern) {
return pos - start;
}
int totalDigits = digitLeftCount + zeroDigitCount + digitRightCount;
maximumFractionDigits = (decimalPos >= 0 ? (totalDigits - decimalPos) : 0);
if (decimalPos >= 0) {
minimumFractionDigits = digitLeftCount + zeroDigitCount - decimalPos;
if (minimumFractionDigits < 0) {
minimumFractionDigits = 0;
}
}
/*
* The effectiveDecimalPos is the position the decimal is at or would be at
* if there is no decimal. Note that if decimalPos<0, then digitTotalCount ==
* digitLeftCount + zeroDigitCount.
*/
int effectiveDecimalPos = decimalPos >= 0 ? decimalPos : totalDigits;
minimumIntegerDigits = effectiveDecimalPos - digitLeftCount;
if (useExponentialNotation) {
maximumIntegerDigits = digitLeftCount + minimumIntegerDigits;
// In exponential display, integer part can't be empty.
if (maximumFractionDigits == 0 && minimumIntegerDigits == 0) {
minimumIntegerDigits = 1;
}
}
this.groupingSize = (groupingCount > 0) ? groupingCount : 0;
decimalSeparatorAlwaysShown = (decimalPos == 0 || decimalPos == totalDigits);
return pos - start;
}
/**
* This method formats a <code>double</code> in exponential format.
*
* @param number value need to be formated
* @param result where the formatted string goes
*/
private void subformatExponential(double number, StringBuffer result) {
if (number == 0.0) {
subformatFixed(number, result, minimumIntegerDigits);
addExponentPart(0, result);
return;
}
int exponent = (int) Math.floor(Math.log(number) / Math.log(10));
number /= Math.pow(10, exponent);
int minIntDigits = minimumIntegerDigits;
if (maximumIntegerDigits > 1 && maximumIntegerDigits > minimumIntegerDigits) {
// A repeating range is defined; adjust to it as follows.
// If repeat == 3, we have 6,5,4=>3; 3,2,1=>0; 0,-1,-2=>-3;
// -3,-4,-5=>-6, etc. This takes into account that the
// exponent we have here is off by one from what we expect;
// it is for the format 0.MMMMMx10^n.
while ((exponent % maximumIntegerDigits) != 0) {
number *= 10;
exponent--;
}
minIntDigits = 1;
} else {
// No repeating range is defined; use minimum integer digits.
if (minimumIntegerDigits < 1) {
exponent++;
number /= 10;
} else {
for (int i = 1; i < minimumIntegerDigits; i++) {
exponent--;
number *= 10;
}
}
}
subformatFixed(number, result, minIntDigits);
addExponentPart(exponent, result);
}
/**
* This method formats a <code>double</code> into a fractional
* representation.
*
* @param number value need to be formated
* @param result result will be written here
* @param minIntDigits minimum integer digits
*/
private void subformatFixed(double number, StringBuffer result,
int minIntDigits) {
double power = Math.pow(10, maximumFractionDigits);
// Use 3 extra digits to allow us to do our own rounding since
// Java rounds up on .5 whereas some browsers might use 'round to even'
// or other rules.
// There are cases where more digits would be required to get
// guaranteed results, but this at least makes such cases rarer.
String fixedString = toFixed(number, maximumFractionDigits + 3);
double intValue = 0, fracValue = 0;
int exponentIndex = fixedString.indexOf('e');
if (exponentIndex != -1) {
// Large numbers may be returned in exponential notation: such numbers
// are integers anyway
intValue = Math.floor(number);
} else {
int decimalIndex = fixedString.indexOf('.');
int len = fixedString.length();
if (decimalIndex == -1) {
decimalIndex = len;
}
if (decimalIndex > 0) {
intValue = Double.parseDouble(fixedString.substring(0, decimalIndex));
}
if (decimalIndex < len - 1) {
fracValue = Double.parseDouble(fixedString.substring(decimalIndex + 1));
fracValue = (((int) fracValue) + 500) / 1000;
if (fracValue >= power) {
fracValue -= power;
intValue++;
}
}
}
boolean fractionPresent = (minimumFractionDigits > 0) || (fracValue > 0);
String intPart = makeIntString(intValue);
String grouping = isCurrencyFormat
? numberConstants.monetaryGroupingSeparator()
: numberConstants.groupingSeparator();
String decimal = isCurrencyFormat ? numberConstants.monetarySeparator()
: numberConstants.decimalSeparator();
int zeroDelta = numberConstants.zeroDigit().charAt(0) - '0';
int digitLen = intPart.length();
if (intValue > 0 || minIntDigits > 0) {
for (int i = digitLen; i < minIntDigits; i++) {
result.append(numberConstants.zeroDigit());
}
for (int i = 0; i < digitLen; i++) {
result.append((char) (intPart.charAt(i) + zeroDelta));
if (digitLen - i > 1 && groupingSize > 0
&& ((digitLen - i) % groupingSize == 1)) {
result.append(grouping);
}
}
} else if (!fractionPresent) {
// If there is no fraction present, and we haven't printed any
// integer digits, then print a zero.
result.append(numberConstants.zeroDigit());
}
// Output the decimal separator if we always do so.
if (decimalSeparatorAlwaysShown || fractionPresent) {
result.append(decimal);
}
// To make sure it lead zero will be kept.
String fracPart = makeIntString(Math.floor(fracValue + power + 0.5d));
int fracLen = fracPart.length();
while (fracPart.charAt(fracLen - 1) == '0' && fracLen > minimumFractionDigits + 1) {
fracLen--;
}
for (int i = 1; i < fracLen; i++) {
result.append((char) (fracPart.charAt(i) + zeroDelta));
}
}
}