DecimalFormat继承自NumberFormat，可以使用它将十进制的数以不同形式格式化为字符串形式，可以控制前导和尾随0、前缀、后缀、分组（千）、小数分隔符等，如果要更改格式符号（例如小数点分隔符）。
它有各种各样的设计使其能够解析和格式化数字的特征区域设置，包括对西方、阿拉伯和印度数字的支持。它也支持不同类型的数字，包括整数（123），定点数字（123.4），科学符号（1.23 e4），百分比（12%），以及货币金额（123美元）。所有这些都可以本地化。
可以将其DecimalFormatSymbols与DecimalFormat类一起使用。这些类在数字格式化方面提供了极大的灵活性，但它们可以代码更加复杂。
包：import java.text.DecimalFormat;
构建模式
使用DecimalFormat模式指定格式设置String的模式属性pattern：
DecimalFormat df = new DecimalFormat(pattern);
关于pattern，有：
数字格式模式语法
可以按照以下BNF（巴科斯范式）图表指定的规则为数字设计自己的格式模式：
pattern： subpattern {; subpattern}
subpattern（子模式）： {prefix} integer {.fraction（分数）} {suffix}
prefix(前缀)：'\\ u0000'..'\\ uFFFD' - specialCharacters
suffix(后缀)：'\\ u0000'..'\\ uFFFD' - specialCharacters
integer：'＃'*'0'*'0'
分数： '0'*'＃'*
上图中使用的符号如下表所示：
| 符号 | 描述 |
|---|---|
X* |
0个或更多个X实例 |
(X | Y) |
X或Y |
X..Y |
从X到Y的任何字符，包括在内 |
S - T |
S中的字符，除了T中的字符 |
{X} |
X是可选的 |
模式中的特殊符号：
| 符号 | 描述 |
| 0 | 一个数字 |
| # | 一个数字，0显示为缺省（即空字符） |
| . | 小数点 |
| ， | 分组分隔符 |
| E | 指数表示的底数指数分隔符 |
| ； | 分隔格式 |
| - | 负号前缀 |
| % | 乘以100并显示为百分比 |
| ？ | 乘以1000并显示为千分比 |
| ¤ | 货币符号; 用货币符号代替; 如果加倍，用国际货币符号代替; 如果存在于模式中，则使用货币小数分隔符而不是小数分隔符 |
| X | 任何其他字符都可以在前缀或者后缀中使用 |
| “ | 用于引号前缀或后缀中的特殊符号 |
示例：
value |
pattern |
output |
说明 |
|---|---|---|---|
| 123456.789 | ###，###。### | 123,456.789 | 井号（＃）表示一个数字，逗号是分组分隔符的占位符，句点是小数分隔符的占位符。 |
| 123456.789 | ###。## | 123456.79 | 将value有三个数字的小数点右边，但pattern只有两个。该format方法通过四舍五入来处理这个问题。 |
| 123.78 | 000000.000 | 000123.780 | 的pattern指定前导和尾随零，因为0字符被用来代替井号（＃）。 |
| 12345.67 | $ ###，###。### | $ 12,345.67 |
pattern美元符号（$）中的第一个字符。请注意，它紧接在格式化的最左边的数字之前output。 |
| 12345.67 | \ u00A5 ###，###。### | ¥12,345.67 | 在pattern与Unicode值00A5指定为日元（¥）货币符号。 |
DecimalFormat df = new DecimalFormat("000.###");
String s = df.format( 1.11111);
System.out.println(s);
//output: 001.111
df.applyPattern("000.000"); //重新应用新的模式
System.out.println(df.format(1.11111));
//output: 001.111
df.applyPattern("000E000");
System.out.println(df.format(1111111));
//output: 111E004 (1111111 约等于111 X 10^4)
df.applyPattern("0E0");
System.out.println(df.format(1000000000));
//output: 1E9
df.applyPattern("###,###,###.###");
System.out.println(df.format(11111111.11));
//output:11,111,111.11
df.applyPattern("0.0%");
System.out.println(df.format(0.1));
//output: 10.0%
df.applyPattern("sd.00"); //可添加其他常规字符
System.out.println(df.format(0.1));
//output: sd.10
区域敏感格式
前面的示例DecimalFormat为默认值创建了一个对象Locale。如果您想要一个DecimalFormat非默认对象Locale，则实例化a NumberFormat然后将其强制转换为DecimalFormat。这是一个例子：
NumberFormat nf = NumberFormat.getNumberInstance（loc）;
DecimalFormat df =（DecimalFormat）nf;
df.applyPattern（图案）;
String output = df.format（value）;
System.out.println（pattern +“”+ output +“”+ loc.toString（））;
运行上一个代码示例将导致后面的输出。格式化的数字位于第二列，具体取决于Locale：
###，###。### 123,456.789 zh_CN
###，###。### 123.456,789 de_DE
###，###。### 123 456,789 fr_FR
到目前为止，这里讨论的格式模式遵循美国英语的惯例。例如，在模式###，###。##中，逗号是千位分隔符，句点表示小数点。如果您的最终用户没有接触到它，那么这个约定很好。但是，某些应用程序（如电子表格和报表生成器）允许最终用户定义自己的格式设置模式。对于这些应用程序，最终用户指定的格式模式应使用本地化表示法。在这些情况下，您将要调用applyLocalizedPattern该DecimalFormat对象上的方法。
改变格式符号
您可以使用 DecimalFormatSymbols类更改format方法生成的格式化数字中出现的符号。这些符号包括小数分隔符，分组分隔符，减号和百分号等。
下一个示例DecimalFormatSymbols通过将奇怪的格式应用于数字来演示该类。这种不寻常的格式是调用的结果setDecimalSeparator，setGroupingSeparator和setGroupingSize方法。
DecimalFormatSymbols unusualSymbols = new DecimalFormatSymbols（currentLocale）;
unusualSymbols.setDecimalSeparator（ '|'）;
unusualSymbols.setGroupingSeparator（ '^'）; String strange =“＃，## 0。###”;
DecimalFormat weirdFormatter = new DecimalFormat（strange，unusualSymbols）;
weirdFormatter.setGroupingSize（4）; String bizarre = weirdFormatter.format（12345.678）;
的System.out.println（奇异）;
运行时，此示例以奇怪的格式打印数字：
1 ^ 2345 | 678 date：
2018-10-31 12:57:51 参考：
https://docs.oracle.com/javase/tutorial/i18n/format/decimalFormat.html#numberpattern 附DecimalFormat类源码：
/*
* Copyright (c) 1996, 2017, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/ /*
* (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved
* (C) Copyright IBM Corp. 1996 - 1998 - All Rights Reserved
*
* The original version of this source code and documentation is copyrighted
* and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These
* materials are provided under terms of a License Agreement between Taligent
* and Sun. This technology is protected by multiple US and International
* patents. This notice and attribution to Taligent may not be removed.
* Taligent is a registered trademark of Taligent, Inc.
*
*/ package java.text; import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.math.RoundingMode;
import java.text.spi.NumberFormatProvider;
import java.util.ArrayList;
import java.util.Currency;
import java.util.Locale;
import java.util.ResourceBundle;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicLong;
import sun.util.locale.provider.LocaleProviderAdapter;
import sun.util.locale.provider.ResourceBundleBasedAdapter; /**
* <code>DecimalFormat</code> is a concrete subclass of
* <code>NumberFormat</code> that formats decimal numbers. It has a variety of
* features designed to make it possible to parse and format numbers in any
* locale, including support for Western, Arabic, and Indic digits. It also
* supports different kinds of numbers, including integers (123), fixed-point
* numbers (123.4), scientific notation (1.23E4), percentages (12%), and
* currency amounts ($123). All of these can be localized.
*
* <p>To obtain a <code>NumberFormat</code> for a specific locale, including the
* default locale, call one of <code>NumberFormat</code>'s factory methods, such
* as <code>getInstance()</code>. In general, do not call the
* <code>DecimalFormat</code> constructors directly, since the
* <code>NumberFormat</code> factory methods may return subclasses other than
* <code>DecimalFormat</code>. If you need to customize the format object, do
* something like this:
*
* <blockquote><pre>
* NumberFormat f = NumberFormat.getInstance(loc);
* if (f instanceof DecimalFormat) {
* ((DecimalFormat) f).setDecimalSeparatorAlwaysShown(true);
* }
* </pre></blockquote>
*
* <p>A <code>DecimalFormat</code> comprises a <em>pattern</em> and a set of
* <em>symbols</em>. The pattern may be set directly using
* <code>applyPattern()</code>, or indirectly using the API methods. The
* symbols are stored in a <code>DecimalFormatSymbols</code> object. When using
* the <code>NumberFormat</code> factory methods, the pattern and symbols are
* read from localized <code>ResourceBundle</code>s.
*
* <h3>Patterns</h3>
*
* <code>DecimalFormat</code> patterns have the following syntax:
* <blockquote><pre>
* <i>Pattern:</i>
* <i>PositivePattern</i>
* <i>PositivePattern</i> ; <i>NegativePattern</i>
* <i>PositivePattern:</i>
* <i>Prefix<sub>opt</sub></i> <i>Number</i> <i>Suffix<sub>opt</sub></i>
* <i>NegativePattern:</i>
* <i>Prefix<sub>opt</sub></i> <i>Number</i> <i>Suffix<sub>opt</sub></i>
* <i>Prefix:</i>
* any Unicode characters except \uFFFE, \uFFFF, and special characters
* <i>Suffix:</i>
* any Unicode characters except \uFFFE, \uFFFF, and special characters
* <i>Number:</i>
* <i>Integer</i> <i>Exponent<sub>opt</sub></i>
* <i>Integer</i> . <i>Fraction</i> <i>Exponent<sub>opt</sub></i>
* <i>Integer:</i>
* <i>MinimumInteger</i>
* #
* # <i>Integer</i>
* # , <i>Integer</i>
* <i>MinimumInteger:</i>
* 0
* 0 <i>MinimumInteger</i>
* 0 , <i>MinimumInteger</i>
* <i>Fraction:</i>
* <i>MinimumFraction<sub>opt</sub></i> <i>OptionalFraction<sub>opt</sub></i>
* <i>MinimumFraction:</i>
* 0 <i>MinimumFraction<sub>opt</sub></i>
* <i>OptionalFraction:</i>
* # <i>OptionalFraction<sub>opt</sub></i>
* <i>Exponent:</i>
* E <i>MinimumExponent</i>
* <i>MinimumExponent:</i>
* 0 <i>MinimumExponent<sub>opt</sub></i>
* </pre></blockquote>
*
* <p>A <code>DecimalFormat</code> pattern contains a positive and negative
* subpattern, for example, <code>"#,##0.00;(#,##0.00)"</code>. Each
* subpattern has a prefix, numeric part, and suffix. The negative subpattern
* is optional; if absent, then the positive subpattern prefixed with the
* localized minus sign (<code>'-'</code> in most locales) is used as the
* negative 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 all the same as the positive
* pattern. That means that <code>"#,##0.0#;(#)"</code> produces precisely
* the same behavior as <code>"#,##0.0#;(#,##0.0#)"</code>.
*
* <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, either the positive and negative prefixes or the
* suffixes must be distinct for <code>DecimalFormat.parse()</code> to be able
* to distinguish positive from negative values. (If they are identical, then
* <code>DecimalFormat</code> will behave as if no negative subpattern was
* specified.) Another example is that the decimal separator and thousands
* separator should be distinct characters, or parsing will be impossible.
*
* <p>The grouping separator is commonly used for thousands, but in some
* countries it separates ten-thousands. The grouping size is a constant number
* of digits between the grouping characters, such as 3 for 100,000,000 or 4 for
* 1,0000,0000. If you supply a pattern with multiple grouping characters, the
* interval between the last one and the end of the integer is the one that is
* used. So <code>"#,##,###,####"</code> == <code>"######,####"</code> ==
* <code>"##,####,####"</code>.
*
* <h4>Special Pattern Characters</h4>
*
* <p>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.
* They must be quoted, unless noted otherwise, if they are to appear in the
* prefix or suffix as literals.
*
* <p>The characters listed here are used in non-localized patterns. Localized
* patterns use the corresponding characters taken from this formatter's
* <code>DecimalFormatSymbols</code> object instead, and these characters lose
* their special status. Two exceptions are the currency sign and quote, which
* are not localized.
*
* <blockquote>
* <table class="striped">
* <caption style="display:none">Chart showing symbol, location, localized, and meaning.</caption>
* <thead>
* <tr>
* <th style="text-align:left">Symbol
* <th style="text-align:left">Location
* <th style="text-align:left">Localized?
* <th style="text-align:left">Meaning
* </thead>
* <tbody>
* <tr style="vertical-align:top">
* <td><code>0</code>
* <td>Number
* <td>Yes
* <td>Digit
* <tr style="vertical-align: top">
* <td><code>#</code>
* <td>Number
* <td>Yes
* <td>Digit, zero shows as absent
* <tr style="vertical-align:top">
* <td><code>.</code>
* <td>Number
* <td>Yes
* <td>Decimal separator or monetary decimal separator
* <tr style="vertical-align: top">
* <td><code>-</code>
* <td>Number
* <td>Yes
* <td>Minus sign
* <tr style="vertical-align:top">
* <td><code>,</code>
* <td>Number
* <td>Yes
* <td>Grouping separator
* <tr style="vertical-align: top">
* <td><code>E</code>
* <td>Number
* <td>Yes
* <td>Separates mantissa and exponent in scientific notation.
* <em>Need not be quoted in prefix or suffix.</em>
* <tr style="vertical-align:top">
* <td><code>;</code>
* <td>Subpattern boundary
* <td>Yes
* <td>Separates positive and negative subpatterns
* <tr style="vertical-align: top">
* <td><code>%</code>
* <td>Prefix or suffix
* <td>Yes
* <td>Multiply by 100 and show as percentage
* <tr style="vertical-align:top">
* <td><code>\u2030</code>
* <td>Prefix or suffix
* <td>Yes
* <td>Multiply by 1000 and show as per mille value
* <tr style="vertical-align: top">
* <td><code>¤</code> (<code>\u00A4</code>)
* <td>Prefix or suffix
* <td>No
* <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.
* <tr style="vertical-align:top">
* <td><code>'</code>
* <td>Prefix or suffix
* <td>No
* <td>Used to quote special characters in a prefix or suffix,
* for example, <code>"'#'#"</code> formats 123 to
* <code>"#123"</code>. To create a single quote
* itself, use two in a row: <code>"# o''clock"</code>.
* </tbody>
* </table>
* </blockquote>
*
* <h4>Scientific Notation</h4>
*
* <p>Numbers in scientific notation are expressed as the product of a mantissa
* and a power of ten, for example, 1234 can be expressed as 1.234 x 10^3. The
* mantissa is often in the range 1.0 ≤ x {@literal <} 10.0, but it need not
* be.
* <code>DecimalFormat</code> can be instructed to format and parse scientific
* notation <em>only via a pattern</em>; there is currently no factory method
* that creates a scientific notation format. In a pattern, the exponent
* character immediately followed by one or more digit characters indicates
* scientific notation. Example: <code>"0.###E0"</code> formats the number
* 1234 as <code>"1.234E3"</code>.
*
* <ul>
* <li>The number of digit characters after the exponent character gives the
* minimum exponent digit count. There is no maximum. Negative exponents are
* formatted using the localized minus sign, <em>not</em> the prefix and suffix
* from the pattern. This allows patterns such as <code>"0.###E0 m/s"</code>.
*
* <li>The minimum and maximum number of integer digits are interpreted
* together:
*
* <ul>
* <li>If the maximum number of integer digits is greater than their minimum number
* and greater than 1, it forces the exponent to be a multiple of the maximum
* number of integer digits, and the minimum number of integer digits to be
* interpreted as 1. The most common use of this is to generate
* <em>engineering notation</em>, in which the exponent is a multiple of three,
* e.g., <code>"##0.#####E0"</code>. Using this pattern, the number 12345
* formats to <code>"12.345E3"</code>, and 123456 formats to
* <code>"123.456E3"</code>.
*
* <li>Otherwise, the minimum number of integer digits is achieved by adjusting the
* exponent. Example: 0.00123 formatted with <code>"00.###E0"</code> yields
* <code>"12.3E-4"</code>.
* </ul>
*
* <li>The number of significant digits in the mantissa is the sum of the
* <em>minimum integer</em> and <em>maximum fraction</em> digits, and is
* unaffected by the maximum integer digits. For example, 12345 formatted with
* <code>"##0.##E0"</code> is <code>"12.3E3"</code>. To show all digits, set
* the significant digits count to zero. The number of significant digits
* does not affect parsing.
*
* <li>Exponential patterns may not contain grouping separators.
* </ul>
*
* <h4>Rounding</h4>
*
* <code>DecimalFormat</code> provides rounding modes defined in
* {@link java.math.RoundingMode} for formatting. By default, it uses
* {@link java.math.RoundingMode#HALF_EVEN RoundingMode.HALF_EVEN}.
*
* <h4>Digits</h4>
*
* For formatting, <code>DecimalFormat</code> uses the ten consecutive
* characters starting with the localized zero digit defined in the
* <code>DecimalFormatSymbols</code> object as digits. For parsing, these
* digits as well as all Unicode decimal digits, as defined by
* {@link Character#digit Character.digit}, are recognized.
*
* <h4>Special Values</h4>
*
* <p><code>NaN</code> is formatted as a string, which typically has a single character
* <code>\uFFFD</code>. This string is determined by the
* <code>DecimalFormatSymbols</code> object. This is the only value for which
* the prefixes and suffixes are not used.
*
* <p>Infinity is formatted as a string, which typically has a single character
* <code>\u221E</code>, with the positive or negative prefixes and suffixes
* applied. The infinity string is determined by the
* <code>DecimalFormatSymbols</code> object.
*
* <p>Negative zero (<code>"-0"</code>) parses to
* <ul>
* <li><code>BigDecimal(0)</code> if <code>isParseBigDecimal()</code> is
* true,
* <li><code>Long(0)</code> if <code>isParseBigDecimal()</code> is false
* and <code>isParseIntegerOnly()</code> is true,
* <li><code>Double(-0.0)</code> if both <code>isParseBigDecimal()</code>
* and <code>isParseIntegerOnly()</code> are false.
* </ul>
*
* <h4><a id="synchronization">Synchronization</a></h4>
*
* <p>
* Decimal formats are generally not synchronized.
* It is recommended to create separate format instances for each thread.
* If multiple threads access a format concurrently, it must be synchronized
* externally.
*
* <h4>Example</h4>
*
* <blockquote><pre>{@code
* <strong>// Print out a number using the localized number, integer, currency,
* // and percent format for each locale</strong>
* Locale[] locales = NumberFormat.getAvailableLocales();
* double myNumber = -1234.56;
* NumberFormat form;
* for (int j = 0; j < 4; ++j) {
* System.out.println("FORMAT");
* for (int i = 0; i < locales.length; ++i) {
* if (locales[i].getCountry().length() == 0) {
* continue; // Skip language-only locales
* }
* System.out.print(locales[i].getDisplayName());
* switch (j) {
* case 0:
* form = NumberFormat.getInstance(locales[i]); break;
* case 1:
* form = NumberFormat.getIntegerInstance(locales[i]); break;
* case 2:
* form = NumberFormat.getCurrencyInstance(locales[i]); break;
* default:
* form = NumberFormat.getPercentInstance(locales[i]); break;
* }
* if (form instanceof DecimalFormat) {
* System.out.print(": " + ((DecimalFormat) form).toPattern());
* }
* System.out.print(" -> " + form.format(myNumber));
* try {
* System.out.println(" -> " + form.parse(form.format(myNumber)));
* } catch (ParseException e) {}
* }
* }
* }</pre></blockquote>
*
* @see <a href="http://docs.oracle.com/javase/tutorial/i18n/format/decimalFormat.html">Java Tutorial</a>
* @see NumberFormat
* @see DecimalFormatSymbols
* @see ParsePosition
* @author Mark Davis
* @author Alan Liu
* @since 1.1
*/
public class DecimalFormat extends NumberFormat { /**
* Creates a DecimalFormat using the default pattern and symbols
* for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale.
* This is a convenient way to obtain a
* DecimalFormat when internationalization is not the main concern.
* <p>
* To obtain standard formats for a given locale, use the factory methods
* on NumberFormat such as getNumberInstance. These factories will
* return the most appropriate sub-class of NumberFormat for a given
* locale.
*
* @see java.text.NumberFormat#getInstance
* @see java.text.NumberFormat#getNumberInstance
* @see java.text.NumberFormat#getCurrencyInstance
* @see java.text.NumberFormat#getPercentInstance
*/
public DecimalFormat() {
// Get the pattern for the default locale.
Locale def = Locale.getDefault(Locale.Category.FORMAT);
LocaleProviderAdapter adapter = LocaleProviderAdapter.getAdapter(NumberFormatProvider.class, def);
if (!(adapter instanceof ResourceBundleBasedAdapter)) {
adapter = LocaleProviderAdapter.getResourceBundleBased();
}
String[] all = adapter.getLocaleResources(def).getNumberPatterns(); // Always applyPattern after the symbols are set
this.symbols = DecimalFormatSymbols.getInstance(def);
applyPattern(all[0], false);
} /**
* Creates a DecimalFormat using the given pattern and the symbols
* for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale.
* This is a convenient way to obtain a
* DecimalFormat when internationalization is not the main concern.
* <p>
* To obtain standard formats for a given locale, use the factory methods
* on NumberFormat such as getNumberInstance. These factories will
* return the most appropriate sub-class of NumberFormat for a given
* locale.
*
* @param pattern a non-localized pattern string.
* @exception NullPointerException if <code>pattern</code> is null
* @exception IllegalArgumentException if the given pattern is invalid.
* @see java.text.NumberFormat#getInstance
* @see java.text.NumberFormat#getNumberInstance
* @see java.text.NumberFormat#getCurrencyInstance
* @see java.text.NumberFormat#getPercentInstance
*/
public DecimalFormat(String pattern) {
// Always applyPattern after the symbols are set
this.symbols = DecimalFormatSymbols.getInstance(Locale.getDefault(Locale.Category.FORMAT));
applyPattern(pattern, false);
} /**
* Creates a DecimalFormat using the given pattern and symbols.
* Use this constructor when you need to completely customize the
* behavior of the format.
* <p>
* To obtain standard formats for a given
* locale, use the factory methods on NumberFormat such as
* getInstance or getCurrencyInstance. If you need only minor adjustments
* to a standard format, you can modify the format returned by
* a NumberFormat factory method.
*
* @param pattern a non-localized pattern string
* @param symbols the set of symbols to be used
* @exception NullPointerException if any of the given arguments is null
* @exception IllegalArgumentException if the given pattern is invalid
* @see java.text.NumberFormat#getInstance
* @see java.text.NumberFormat#getNumberInstance
* @see java.text.NumberFormat#getCurrencyInstance
* @see java.text.NumberFormat#getPercentInstance
* @see java.text.DecimalFormatSymbols
*/
public DecimalFormat (String pattern, DecimalFormatSymbols symbols) {
// Always applyPattern after the symbols are set
this.symbols = (DecimalFormatSymbols)symbols.clone();
applyPattern(pattern, false);
} // Overrides
/**
* Formats a number and appends the resulting text to the given string
* buffer.
* The number can be of any subclass of {@link java.lang.Number}.
* <p>
* This implementation uses the maximum precision permitted.
* @param number the number to format
* @param toAppendTo the <code>StringBuffer</code> to which the formatted
* text is to be appended
* @param pos On input: an alignment field, if desired.
* On output: the offsets of the alignment field.
* @return the value passed in as <code>toAppendTo</code>
* @exception IllegalArgumentException if <code>number</code> is
* null or not an instance of <code>Number</code>.
* @exception NullPointerException if <code>toAppendTo</code> or
* <code>pos</code> is null
* @exception ArithmeticException if rounding is needed with rounding
* mode being set to RoundingMode.UNNECESSARY
* @see java.text.FieldPosition
*/
@Override
public final StringBuffer format(Object number,
StringBuffer toAppendTo,
FieldPosition pos) {
if (number instanceof Long || number instanceof Integer ||
number instanceof Short || number instanceof Byte ||
number instanceof AtomicInteger ||
number instanceof AtomicLong ||
(number instanceof BigInteger &&
((BigInteger)number).bitLength () < 64)) {
return format(((Number)number).longValue(), toAppendTo, pos);
} else if (number instanceof BigDecimal) {
return format((BigDecimal)number, toAppendTo, pos);
} else if (number instanceof BigInteger) {
return format((BigInteger)number, toAppendTo, pos);
} else if (number instanceof Number) {
return format(((Number)number).doubleValue(), toAppendTo, pos);
} else {
throw new IllegalArgumentException("Cannot format given Object as a Number");
}
} /**
* Formats a double to produce a string.
* @param number The double to format
* @param result where the text is to be appended
* @param fieldPosition On input: an alignment field, if desired.
* On output: the offsets of the alignment field.
* @exception NullPointerException if {@code result} or
* {@code fieldPosition} is {@code null}
* @exception ArithmeticException if rounding is needed with rounding
* mode being set to RoundingMode.UNNECESSARY
* @return The formatted number string
* @see java.text.FieldPosition
*/
@Override
public StringBuffer format(double number, StringBuffer result,
FieldPosition fieldPosition) {
// If fieldPosition is a DontCareFieldPosition instance we can
// try to go to fast-path code.
boolean tryFastPath = false;
if (fieldPosition == DontCareFieldPosition.INSTANCE)
tryFastPath = true;
else {
fieldPosition.setBeginIndex(0);
fieldPosition.setEndIndex(0);
} if (tryFastPath) {
String tempResult = fastFormat(number);
if (tempResult != null) {
result.append(tempResult);
return result;
}
} // if fast-path could not work, we fallback to standard code.
return format(number, result, fieldPosition.getFieldDelegate());
} /**
* Formats a double to produce a string.
* @param number The double to format
* @param result where the text is to be appended
* @param delegate notified of locations of sub fields
* @exception ArithmeticException if rounding is needed with rounding
* mode being set to RoundingMode.UNNECESSARY
* @return The formatted number string
*/
private StringBuffer format(double number, StringBuffer result,
FieldDelegate delegate) {
if (Double.isNaN(number) ||
(Double.isInfinite(number) && multiplier == 0)) {
int iFieldStart = result.length();
result.append(symbols.getNaN());
delegate.formatted(INTEGER_FIELD, Field.INTEGER, Field.INTEGER,
iFieldStart, result.length(), result);
return result;
} /* Detecting whether a double is negative is easy with the exception of
* the value -0.0. This is a double which has a zero mantissa (and
* exponent), but a negative sign bit. It is semantically distinct from
* a zero with a positive sign bit, and this distinction is important
* to certain kinds of computations. However, it's a little tricky to
* detect, since (-0.0 == 0.0) and !(-0.0 < 0.0). How then, you may
* ask, does it behave distinctly from +0.0? Well, 1/(-0.0) ==
* -Infinity. Proper detection of -0.0 is needed to deal with the
* issues raised by bugs 4106658, 4106667, and 4147706. Liu 7/6/98.
*/
boolean isNegative = ((number < 0.0) || (number == 0.0 && 1/number < 0.0)) ^ (multiplier < 0); if (multiplier != 1) {
number *= multiplier;
} if (Double.isInfinite(number)) {
if (isNegative) {
append(result, negativePrefix, delegate,
getNegativePrefixFieldPositions(), Field.SIGN);
} else {
append(result, positivePrefix, delegate,
getPositivePrefixFieldPositions(), Field.SIGN);
} int iFieldStart = result.length();
result.append(symbols.getInfinity());
delegate.formatted(INTEGER_FIELD, Field.INTEGER, Field.INTEGER,
iFieldStart, result.length(), result); if (isNegative) {
append(result, negativeSuffix, delegate,
getNegativeSuffixFieldPositions(), Field.SIGN);
} else {
append(result, positiveSuffix, delegate,
getPositiveSuffixFieldPositions(), Field.SIGN);
} return result;
} if (isNegative) {
number = -number;
} // at this point we are guaranteed a nonnegative finite number.
assert(number >= 0 && !Double.isInfinite(number)); synchronized(digitList) {
int maxIntDigits = super.getMaximumIntegerDigits();
int minIntDigits = super.getMinimumIntegerDigits();
int maxFraDigits = super.getMaximumFractionDigits();
int minFraDigits = super.getMinimumFractionDigits(); digitList.set(isNegative, number, useExponentialNotation ?
maxIntDigits + maxFraDigits : maxFraDigits,
!useExponentialNotation);
return subformat(result, delegate, isNegative, false,
maxIntDigits, minIntDigits, maxFraDigits, minFraDigits);
}
} /**
* Format a long to produce a string.
* @param number The long to format
* @param result where the text is to be appended
* @param fieldPosition On input: an alignment field, if desired.
* On output: the offsets of the alignment field.
* @exception NullPointerException if {@code result} or
* {@code fieldPosition} is {@code null}
* @exception ArithmeticException if rounding is needed with rounding
* mode being set to RoundingMode.UNNECESSARY
* @return The formatted number string
* @see java.text.FieldPosition
*/
@Override
public StringBuffer format(long number, StringBuffer result,
FieldPosition fieldPosition) {
fieldPosition.setBeginIndex(0);
fieldPosition.setEndIndex(0); return format(number, result, fieldPosition.getFieldDelegate());
} /**
* Format a long to produce a string.
* @param number The long to format
* @param result where the text is to be appended
* @param delegate notified of locations of sub fields
* @return The formatted number string
* @exception ArithmeticException if rounding is needed with rounding
* mode being set to RoundingMode.UNNECESSARY
* @see java.text.FieldPosition
*/
private StringBuffer format(long number, StringBuffer result,
FieldDelegate delegate) {
boolean isNegative = (number < 0);
if (isNegative) {
number = -number;
} // In general, long values always represent real finite numbers, so
// we don't have to check for +/- Infinity or NaN. However, there
// is one case we have to be careful of: The multiplier can push
// a number near MIN_VALUE or MAX_VALUE outside the legal range. We
// check for this before multiplying, and if it happens we use
// BigInteger instead.
boolean useBigInteger = false;
if (number < 0) { // This can only happen if number == Long.MIN_VALUE.
if (multiplier != 0) {
useBigInteger = true;
}
} else if (multiplier != 1 && multiplier != 0) {
long cutoff = Long.MAX_VALUE / multiplier;
if (cutoff < 0) {
cutoff = -cutoff;
}
useBigInteger = (number > cutoff);
} if (useBigInteger) {
if (isNegative) {
number = -number;
}
BigInteger bigIntegerValue = BigInteger.valueOf(number);
return format(bigIntegerValue, result, delegate, true);
} number *= multiplier;
if (number == 0) {
isNegative = false;
} else {
if (multiplier < 0) {
number = -number;
isNegative = !isNegative;
}
} synchronized(digitList) {
int maxIntDigits = super.getMaximumIntegerDigits();
int minIntDigits = super.getMinimumIntegerDigits();
int maxFraDigits = super.getMaximumFractionDigits();
int minFraDigits = super.getMinimumFractionDigits(); digitList.set(isNegative, number,
useExponentialNotation ? maxIntDigits + maxFraDigits : 0); return subformat(result, delegate, isNegative, true,
maxIntDigits, minIntDigits, maxFraDigits, minFraDigits);
}
} /**
* Formats a BigDecimal to produce a string.
* @param number The BigDecimal to format
* @param result where the text is to be appended
* @param fieldPosition On input: an alignment field, if desired.
* On output: the offsets of the alignment field.
* @return The formatted number string
* @exception ArithmeticException if rounding is needed with rounding
* mode being set to RoundingMode.UNNECESSARY
* @see java.text.FieldPosition
*/
private StringBuffer format(BigDecimal number, StringBuffer result,
FieldPosition fieldPosition) {
fieldPosition.setBeginIndex(0);
fieldPosition.setEndIndex(0);
return format(number, result, fieldPosition.getFieldDelegate());
} /**
* Formats a BigDecimal to produce a string.
* @param number The BigDecimal to format
* @param result where the text is to be appended
* @param delegate notified of locations of sub fields
* @exception ArithmeticException if rounding is needed with rounding
* mode being set to RoundingMode.UNNECESSARY
* @return The formatted number string
*/
private StringBuffer format(BigDecimal number, StringBuffer result,
FieldDelegate delegate) {
if (multiplier != 1) {
number = number.multiply(getBigDecimalMultiplier());
}
boolean isNegative = number.signum() == -1;
if (isNegative) {
number = number.negate();
} synchronized(digitList) {
int maxIntDigits = getMaximumIntegerDigits();
int minIntDigits = getMinimumIntegerDigits();
int maxFraDigits = getMaximumFractionDigits();
int minFraDigits = getMinimumFractionDigits();
int maximumDigits = maxIntDigits + maxFraDigits; digitList.set(isNegative, number, useExponentialNotation ?
((maximumDigits < 0) ? Integer.MAX_VALUE : maximumDigits) :
maxFraDigits, !useExponentialNotation); return subformat(result, delegate, isNegative, false,
maxIntDigits, minIntDigits, maxFraDigits, minFraDigits);
}
} /**
* Format a BigInteger to produce a string.
* @param number The BigInteger to format
* @param result where the text is to be appended
* @param fieldPosition On input: an alignment field, if desired.
* On output: the offsets of the alignment field.
* @return The formatted number string
* @exception ArithmeticException if rounding is needed with rounding
* mode being set to RoundingMode.UNNECESSARY
* @see java.text.FieldPosition
*/
private StringBuffer format(BigInteger number, StringBuffer result,
FieldPosition fieldPosition) {
fieldPosition.setBeginIndex(0);
fieldPosition.setEndIndex(0); return format(number, result, fieldPosition.getFieldDelegate(), false);
} /**
* Format a BigInteger to produce a string.
* @param number The BigInteger to format
* @param result where the text is to be appended
* @param delegate notified of locations of sub fields
* @return The formatted number string
* @exception ArithmeticException if rounding is needed with rounding
* mode being set to RoundingMode.UNNECESSARY
* @see java.text.FieldPosition
*/
private StringBuffer format(BigInteger number, StringBuffer result,
FieldDelegate delegate, boolean formatLong) {
if (multiplier != 1) {
number = number.multiply(getBigIntegerMultiplier());
}
boolean isNegative = number.signum() == -1;
if (isNegative) {
number = number.negate();
} synchronized(digitList) {
int maxIntDigits, minIntDigits, maxFraDigits, minFraDigits, maximumDigits;
if (formatLong) {
maxIntDigits = super.getMaximumIntegerDigits();
minIntDigits = super.getMinimumIntegerDigits();
maxFraDigits = super.getMaximumFractionDigits();
minFraDigits = super.getMinimumFractionDigits();
maximumDigits = maxIntDigits + maxFraDigits;
} else {
maxIntDigits = getMaximumIntegerDigits();
minIntDigits = getMinimumIntegerDigits();
maxFraDigits = getMaximumFractionDigits();
minFraDigits = getMinimumFractionDigits();
maximumDigits = maxIntDigits + maxFraDigits;
if (maximumDigits < 0) {
maximumDigits = Integer.MAX_VALUE;
}
} digitList.set(isNegative, number,
useExponentialNotation ? maximumDigits : 0); return subformat(result, delegate, isNegative, true,
maxIntDigits, minIntDigits, maxFraDigits, minFraDigits);
}
} /**
* Formats an Object producing an <code>AttributedCharacterIterator</code>.
* You can use the returned <code>AttributedCharacterIterator</code>
* to build the resulting String, as well as to determine information
* about the resulting String.
* <p>
* Each attribute key of the AttributedCharacterIterator will be of type
* <code>NumberFormat.Field</code>, with the attribute value being the
* same as the attribute key.
*
* @exception NullPointerException if obj is null.
* @exception IllegalArgumentException when the Format cannot format the
* given object.
* @exception ArithmeticException if rounding is needed with rounding
* mode being set to RoundingMode.UNNECESSARY
* @param obj The object to format
* @return AttributedCharacterIterator describing the formatted value.
* @since 1.4
*/
@Override
public AttributedCharacterIterator formatToCharacterIterator(Object obj) {
CharacterIteratorFieldDelegate delegate =
new CharacterIteratorFieldDelegate();
StringBuffer sb = new StringBuffer(); if (obj instanceof Double || obj instanceof Float) {
format(((Number)obj).doubleValue(), sb, delegate);
} else if (obj instanceof Long || obj instanceof Integer ||
obj instanceof Short || obj instanceof Byte ||
obj instanceof AtomicInteger || obj instanceof AtomicLong) {
format(((Number)obj).longValue(), sb, delegate);
} else if (obj instanceof BigDecimal) {
format((BigDecimal)obj, sb, delegate);
} else if (obj instanceof BigInteger) {
format((BigInteger)obj, sb, delegate, false);
} else if (obj == null) {
throw new NullPointerException(
"formatToCharacterIterator must be passed non-null object");
} else {
throw new IllegalArgumentException(
"Cannot format given Object as a Number");
}
return delegate.getIterator(sb.toString());
} // ==== Begin fast-path formating logic for double ========================= /* Fast-path formatting will be used for format(double ...) methods iff a
* number of conditions are met (see checkAndSetFastPathStatus()):
* - Only if instance properties meet the right predefined conditions.
* - The abs value of the double to format is <= Integer.MAX_VALUE.
*
* The basic approach is to split the binary to decimal conversion of a
* double value into two phases:
* * The conversion of the integer portion of the double.
* * The conversion of the fractional portion of the double
* (limited to two or three digits).
*
* The isolation and conversion of the integer portion of the double is
* straightforward. The conversion of the fraction is more subtle and relies
* on some rounding properties of double to the decimal precisions in
* question. Using the terminology of BigDecimal, this fast-path algorithm
* is applied when a double value has a magnitude less than Integer.MAX_VALUE
* and rounding is to nearest even and the destination format has two or
* three digits of *scale* (digits after the decimal point).
*
* Under a rounding to nearest even policy, the returned result is a digit
* string of a number in the (in this case decimal) destination format
* closest to the exact numerical value of the (in this case binary) input
* value. If two destination format numbers are equally distant, the one
* with the last digit even is returned. To compute such a correctly rounded
* value, some information about digits beyond the smallest returned digit
* position needs to be consulted.
*
* In general, a guard digit, a round digit, and a sticky *bit* are needed
* beyond the returned digit position. If the discarded portion of the input
* is sufficiently large, the returned digit string is incremented. In round
* to nearest even, this threshold to increment occurs near the half-way
* point between digits. The sticky bit records if there are any remaining
* trailing digits of the exact input value in the new format; the sticky bit
* is consulted only in close to half-way rounding cases.
*
* Given the computation of the digit and bit values, rounding is then
* reduced to a table lookup problem. For decimal, the even/odd cases look
* like this:
*
* Last Round Sticky
* 6 5 0 => 6 // exactly halfway, return even digit.
* 6 5 1 => 7 // a little bit more than halfway, round up.
* 7 5 0 => 8 // exactly halfway, round up to even.
* 7 5 1 => 8 // a little bit more than halfway, round up.
* With analogous entries for other even and odd last-returned digits.
*
* However, decimal negative powers of 5 smaller than 0.5 are *not* exactly
* representable as binary fraction. In particular, 0.005 (the round limit
* for a two-digit scale) and 0.0005 (the round limit for a three-digit
* scale) are not representable. Therefore, for input values near these cases
* the sticky bit is known to be set which reduces the rounding logic to:
*
* Last Round Sticky
* 6 5 1 => 7 // a little bit more than halfway, round up.
* 7 5 1 => 8 // a little bit more than halfway, round up.
*
* In other words, if the round digit is 5, the sticky bit is known to be
* set. If the round digit is something other than 5, the sticky bit is not
* relevant. Therefore, some of the logic about whether or not to increment
* the destination *decimal* value can occur based on tests of *binary*
* computations of the binary input number.
*/ /**
* Check validity of using fast-path for this instance. If fast-path is valid
* for this instance, sets fast-path state as true and initializes fast-path
* utility fields as needed.
*
* This method is supposed to be called rarely, otherwise that will break the
* fast-path performance. That means avoiding frequent changes of the
* properties of the instance, since for most properties, each time a change
* happens, a call to this method is needed at the next format call.
*
* FAST-PATH RULES:
* Similar to the default DecimalFormat instantiation case.
* More precisely:
* - HALF_EVEN rounding mode,
* - isGroupingUsed() is true,
* - groupingSize of 3,
* - multiplier is 1,
* - Decimal separator not mandatory,
* - No use of exponential notation,
* - minimumIntegerDigits is exactly 1 and maximumIntegerDigits at least 10
* - For number of fractional digits, the exact values found in the default case:
* Currency : min = max = 2.
* Decimal : min = 0. max = 3.
*
*/
private boolean checkAndSetFastPathStatus() { boolean fastPathWasOn = isFastPath; if ((roundingMode == RoundingMode.HALF_EVEN) &&
(isGroupingUsed()) &&
(groupingSize == 3) &&
(multiplier == 1) &&
(!decimalSeparatorAlwaysShown) &&
(!useExponentialNotation)) { // The fast-path algorithm is semi-hardcoded against
// minimumIntegerDigits and maximumIntegerDigits.
isFastPath = ((minimumIntegerDigits == 1) &&
(maximumIntegerDigits >= 10)); // The fast-path algorithm is hardcoded against
// minimumFractionDigits and maximumFractionDigits.
if (isFastPath) {
if (isCurrencyFormat) {
if ((minimumFractionDigits != 2) ||
(maximumFractionDigits != 2))
isFastPath = false;
} else if ((minimumFractionDigits != 0) ||
(maximumFractionDigits != 3))
isFastPath = false;
}
} else
isFastPath = false; resetFastPathData(fastPathWasOn);
fastPathCheckNeeded = false; /*
* Returns true after successfully checking the fast path condition and
* setting the fast path data. The return value is used by the
* fastFormat() method to decide whether to call the resetFastPathData
* method to reinitialize fast path data or is it already initialized
* in this method.
*/
return true;
} private void resetFastPathData(boolean fastPathWasOn) {
// Since some instance properties may have changed while still falling
// in the fast-path case, we need to reinitialize fastPathData anyway.
if (isFastPath) {
// We need to instantiate fastPathData if not already done.
if (fastPathData == null) {
fastPathData = new FastPathData();
} // Sets up the locale specific constants used when formatting.
// '0' is our default representation of zero.
fastPathData.zeroDelta = symbols.getZeroDigit() - '0';
fastPathData.groupingChar = symbols.getGroupingSeparator(); // Sets up fractional constants related to currency/decimal pattern.
fastPathData.fractionalMaxIntBound = (isCurrencyFormat)
? 99 : 999;
fastPathData.fractionalScaleFactor = (isCurrencyFormat)
? 100.0d : 1000.0d; // Records the need for adding prefix or suffix
fastPathData.positiveAffixesRequired
= (positivePrefix.length() != 0)
|| (positiveSuffix.length() != 0);
fastPathData.negativeAffixesRequired
= (negativePrefix.length() != 0)
|| (negativeSuffix.length() != 0); // Creates a cached char container for result, with max possible size.
int maxNbIntegralDigits = 10;
int maxNbGroups = 3;
int containerSize
= Math.max(positivePrefix.length(), negativePrefix.length())
+ maxNbIntegralDigits + maxNbGroups + 1
+ maximumFractionDigits
+ Math.max(positiveSuffix.length(), negativeSuffix.length()); fastPathData.fastPathContainer = new char[containerSize]; // Sets up prefix and suffix char arrays constants.
fastPathData.charsPositiveSuffix = positiveSuffix.toCharArray();
fastPathData.charsNegativeSuffix = negativeSuffix.toCharArray();
fastPathData.charsPositivePrefix = positivePrefix.toCharArray();
fastPathData.charsNegativePrefix = negativePrefix.toCharArray(); // Sets up fixed index positions for integral and fractional digits.
// Sets up decimal point in cached result container.
int longestPrefixLength
= Math.max(positivePrefix.length(),
negativePrefix.length());
int decimalPointIndex
= maxNbIntegralDigits + maxNbGroups + longestPrefixLength; fastPathData.integralLastIndex = decimalPointIndex - 1;
fastPathData.fractionalFirstIndex = decimalPointIndex + 1;
fastPathData.fastPathContainer[decimalPointIndex]
= isCurrencyFormat
? symbols.getMonetaryDecimalSeparator()
: symbols.getDecimalSeparator(); } else if (fastPathWasOn) {
// Previous state was fast-path and is no more.
// Resets cached array constants.
fastPathData.fastPathContainer = null;
fastPathData.charsPositiveSuffix = null;
fastPathData.charsNegativeSuffix = null;
fastPathData.charsPositivePrefix = null;
fastPathData.charsNegativePrefix = null;
}
} /**
* Returns true if rounding-up must be done on {@code scaledFractionalPartAsInt},
* false otherwise.
*
* This is a utility method that takes correct half-even rounding decision on
* passed fractional value at the scaled decimal point (2 digits for currency
* case and 3 for decimal case), when the approximated fractional part after
* scaled decimal point is exactly 0.5d. This is done by means of exact
* calculations on the {@code fractionalPart} floating-point value.
*
* This method is supposed to be called by private {@code fastDoubleFormat}
* method only.
*
* The algorithms used for the exact calculations are :
*
* The <b><i>FastTwoSum</i></b> algorithm, from T.J.Dekker, described in the
* papers "<i>A Floating-Point Technique for Extending the Available
* Precision</i>" by Dekker, and in "<i>Adaptive Precision Floating-Point
* Arithmetic and Fast Robust Geometric Predicates</i>" from J.Shewchuk.
*
* A modified version of <b><i>Sum2S</i></b> cascaded summation described in
* "<i>Accurate Sum and Dot Product</i>" from Takeshi Ogita and All. As
* Ogita says in this paper this is an equivalent of the Kahan-Babuska's
* summation algorithm because we order the terms by magnitude before summing
* them. For this reason we can use the <i>FastTwoSum</i> algorithm rather
* than the more expensive Knuth's <i>TwoSum</i>.
*
* We do this to avoid a more expensive exact "<i>TwoProduct</i>" algorithm,
* like those described in Shewchuk's paper above. See comments in the code
* below.
*
* @param fractionalPart The fractional value on which we take rounding
* decision.
* @param scaledFractionalPartAsInt The integral part of the scaled
* fractional value.
*
* @return the decision that must be taken regarding half-even rounding.
*/
private boolean exactRoundUp(double fractionalPart,
int scaledFractionalPartAsInt) { /* exactRoundUp() method is called by fastDoubleFormat() only.
* The precondition expected to be verified by the passed parameters is :
* scaledFractionalPartAsInt ==
* (int) (fractionalPart * fastPathData.fractionalScaleFactor).
* This is ensured by fastDoubleFormat() code.
*/ /* We first calculate roundoff error made by fastDoubleFormat() on
* the scaled fractional part. We do this with exact calculation on the
* passed fractionalPart. Rounding decision will then be taken from roundoff.
*/ /* ---- TwoProduct(fractionalPart, scale factor (i.e. 1000.0d or 100.0d)).
*
* The below is an optimized exact "TwoProduct" calculation of passed
* fractional part with scale factor, using Ogita's Sum2S cascaded
* summation adapted as Kahan-Babuska equivalent by using FastTwoSum
* (much faster) rather than Knuth's TwoSum.
*
* We can do this because we order the summation from smallest to
* greatest, so that FastTwoSum can be used without any additional error.
*
* The "TwoProduct" exact calculation needs 17 flops. We replace this by
* a cascaded summation of FastTwoSum calculations, each involving an
* exact multiply by a power of 2.
*
* Doing so saves overall 4 multiplications and 1 addition compared to
* using traditional "TwoProduct".
*
* The scale factor is either 100 (currency case) or 1000 (decimal case).
* - when 1000, we replace it by (1024 - 16 - 8) = 1000.
* - when 100, we replace it by (128 - 32 + 4) = 100.
* Every multiplication by a power of 2 (1024, 128, 32, 16, 8, 4) is exact.
*
*/
double approxMax; // Will always be positive.
double approxMedium; // Will always be negative.
double approxMin; double fastTwoSumApproximation = 0.0d;
double fastTwoSumRoundOff = 0.0d;
double bVirtual = 0.0d; if (isCurrencyFormat) {
// Scale is 100 = 128 - 32 + 4.
// Multiply by 2**n is a shift. No roundoff. No error.
approxMax = fractionalPart * 128.00d;
approxMedium = - (fractionalPart * 32.00d);
approxMin = fractionalPart * 4.00d;
} else {
// Scale is 1000 = 1024 - 16 - 8.
// Multiply by 2**n is a shift. No roundoff. No error.
approxMax = fractionalPart * 1024.00d;
approxMedium = - (fractionalPart * 16.00d);
approxMin = - (fractionalPart * 8.00d);
} // Shewchuk/Dekker's FastTwoSum(approxMedium, approxMin).
assert(-approxMedium >= Math.abs(approxMin));
fastTwoSumApproximation = approxMedium + approxMin;
bVirtual = fastTwoSumApproximation - approxMedium;
fastTwoSumRoundOff = approxMin - bVirtual;
double approxS1 = fastTwoSumApproximation;
double roundoffS1 = fastTwoSumRoundOff; // Shewchuk/Dekker's FastTwoSum(approxMax, approxS1);
assert(approxMax >= Math.abs(approxS1));
fastTwoSumApproximation = approxMax + approxS1;
bVirtual = fastTwoSumApproximation - approxMax;
fastTwoSumRoundOff = approxS1 - bVirtual;
double roundoff1000 = fastTwoSumRoundOff;
double approx1000 = fastTwoSumApproximation;
double roundoffTotal = roundoffS1 + roundoff1000; // Shewchuk/Dekker's FastTwoSum(approx1000, roundoffTotal);
assert(approx1000 >= Math.abs(roundoffTotal));
fastTwoSumApproximation = approx1000 + roundoffTotal;
bVirtual = fastTwoSumApproximation - approx1000; // Now we have got the roundoff for the scaled fractional
double scaledFractionalRoundoff = roundoffTotal - bVirtual; // ---- TwoProduct(fractionalPart, scale (i.e. 1000.0d or 100.0d)) end. /* ---- Taking the rounding decision
*
* We take rounding decision based on roundoff and half-even rounding
* rule.
*
* The above TwoProduct gives us the exact roundoff on the approximated
* scaled fractional, and we know that this approximation is exactly
* 0.5d, since that has already been tested by the caller
* (fastDoubleFormat).
*
* Decision comes first from the sign of the calculated exact roundoff.
* - Since being exact roundoff, it cannot be positive with a scaled
* fractional less than 0.5d, as well as negative with a scaled
* fractional greater than 0.5d. That leaves us with following 3 cases.
* - positive, thus scaled fractional == 0.500....0fff ==> round-up.
* - negative, thus scaled fractional == 0.499....9fff ==> don't round-up.
* - is zero, thus scaled fractioanl == 0.5 ==> half-even rounding applies :
* we round-up only if the integral part of the scaled fractional is odd.
*
*/
if (scaledFractionalRoundoff > 0.0) {
return true;
} else if (scaledFractionalRoundoff < 0.0) {
return false;
} else if ((scaledFractionalPartAsInt & 1) != 0) {
return true;
} return false; // ---- Taking the rounding decision end
} /**
* Collects integral digits from passed {@code number}, while setting
* grouping chars as needed. Updates {@code firstUsedIndex} accordingly.
*
* Loops downward starting from {@code backwardIndex} position (inclusive).
*
* @param number The int value from which we collect digits.
* @param digitsBuffer The char array container where digits and grouping chars
* are stored.
* @param backwardIndex the position from which we start storing digits in
* digitsBuffer.
*
*/
private void collectIntegralDigits(int number,
char[] digitsBuffer,
int backwardIndex) {
int index = backwardIndex;
int q;
int r;
while (number > 999) {
// Generates 3 digits per iteration.
q = number / 1000;
r = number - (q << 10) + (q << 4) + (q << 3); // -1024 +16 +8 = 1000.
number = q; digitsBuffer[index--] = DigitArrays.DigitOnes1000[r];
digitsBuffer[index--] = DigitArrays.DigitTens1000[r];
digitsBuffer[index--] = DigitArrays.DigitHundreds1000[r];
digitsBuffer[index--] = fastPathData.groupingChar;
} // Collects last 3 or less digits.
digitsBuffer[index] = DigitArrays.DigitOnes1000[number];
if (number > 9) {
digitsBuffer[--index] = DigitArrays.DigitTens1000[number];
if (number > 99)
digitsBuffer[--index] = DigitArrays.DigitHundreds1000[number];
} fastPathData.firstUsedIndex = index;
} /**
* Collects the 2 (currency) or 3 (decimal) fractional digits from passed
* {@code number}, starting at {@code startIndex} position
* inclusive. There is no punctuation to set here (no grouping chars).
* Updates {@code fastPathData.lastFreeIndex} accordingly.
*
*
* @param number The int value from which we collect digits.
* @param digitsBuffer The char array container where digits are stored.
* @param startIndex the position from which we start storing digits in
* digitsBuffer.
*
*/
private void collectFractionalDigits(int number,
char[] digitsBuffer,
int startIndex) {
int index = startIndex; char digitOnes = DigitArrays.DigitOnes1000[number];
char digitTens = DigitArrays.DigitTens1000[number]; if (isCurrencyFormat) {
// Currency case. Always collects fractional digits.
digitsBuffer[index++] = digitTens;
digitsBuffer[index++] = digitOnes;
} else if (number != 0) {
// Decimal case. Hundreds will always be collected
digitsBuffer[index++] = DigitArrays.DigitHundreds1000[number]; // Ending zeros won't be collected.
if (digitOnes != '0') {
digitsBuffer[index++] = digitTens;
digitsBuffer[index++] = digitOnes;
} else if (digitTens != '0')
digitsBuffer[index++] = digitTens; } else
// This is decimal pattern and fractional part is zero.
// We must remove decimal point from result.
index--; fastPathData.lastFreeIndex = index;
} /**
* Internal utility.
* Adds the passed {@code prefix} and {@code suffix} to {@code container}.
*
* @param container Char array container which to prepend/append the
* prefix/suffix.
* @param prefix Char sequence to prepend as a prefix.
* @param suffix Char sequence to append as a suffix.
*
*/
// private void addAffixes(boolean isNegative, char[] container) {
private void addAffixes(char[] container, char[] prefix, char[] suffix) { // We add affixes only if needed (affix length > 0).
int pl = prefix.length;
int sl = suffix.length;
if (pl != 0) prependPrefix(prefix, pl, container);
if (sl != 0) appendSuffix(suffix, sl, container); } /**
* Prepends the passed {@code prefix} chars to given result
* {@code container}. Updates {@code fastPathData.firstUsedIndex}
* accordingly.
*
* @param prefix The prefix characters to prepend to result.
* @param len The number of chars to prepend.
* @param container Char array container which to prepend the prefix
*/
private void prependPrefix(char[] prefix,
int len,
char[] container) { fastPathData.firstUsedIndex -= len;
int startIndex = fastPathData.firstUsedIndex; // If prefix to prepend is only 1 char long, just assigns this char.
// If prefix is less or equal 4, we use a dedicated algorithm that
// has shown to run faster than System.arraycopy.
// If more than 4, we use System.arraycopy.
if (len == 1)
container[startIndex] = prefix[0];
else if (len <= 4) {
int dstLower = startIndex;
int dstUpper = dstLower + len - 1;
int srcUpper = len - 1;
container[dstLower] = prefix[0];
container[dstUpper] = prefix[srcUpper]; if (len > 2)
container[++dstLower] = prefix[1];
if (len == 4)
container[--dstUpper] = prefix[2];
} else
System.arraycopy(prefix, 0, container, startIndex, len);
} /**
* Appends the passed {@code suffix} chars to given result
* {@code container}. Updates {@code fastPathData.lastFreeIndex}
* accordingly.
*
* @param suffix The suffix characters to append to result.
* @param len The number of chars to append.
* @param container Char array container which to append the suffix
*/
private void appendSuffix(char[] suffix,
int len,
char[] container) { int startIndex = fastPathData.lastFreeIndex; // If suffix to append is only 1 char long, just assigns this char.
// If suffix is less or equal 4, we use a dedicated algorithm that
// has shown to run faster than System.arraycopy.
// If more than 4, we use System.arraycopy.
if (len == 1)
container[startIndex] = suffix[0];
else if (len <= 4) {
int dstLower = startIndex;
int dstUpper = dstLower + len - 1;
int srcUpper = len - 1;
container[dstLower] = suffix[0];
container[dstUpper] = suffix[srcUpper]; if (len > 2)
container[++dstLower] = suffix[1];
if (len == 4)
container[--dstUpper] = suffix[2];
} else
System.arraycopy(suffix, 0, container, startIndex, len); fastPathData.lastFreeIndex += len;
} /**
* Converts digit chars from {@code digitsBuffer} to current locale.
*
* Must be called before adding affixes since we refer to
* {@code fastPathData.firstUsedIndex} and {@code fastPathData.lastFreeIndex},
* and do not support affixes (for speed reason).
*
* We loop backward starting from last used index in {@code fastPathData}.
*
* @param digitsBuffer The char array container where the digits are stored.
*/
private void localizeDigits(char[] digitsBuffer) { // We will localize only the digits, using the groupingSize,
// and taking into account fractional part. // First take into account fractional part.
int digitsCounter =
fastPathData.lastFreeIndex - fastPathData.fractionalFirstIndex; // The case when there is no fractional digits.
if (digitsCounter < 0)
digitsCounter = groupingSize; // Only the digits remains to localize.
for (int cursor = fastPathData.lastFreeIndex - 1;
cursor >= fastPathData.firstUsedIndex;
cursor--) {
if (digitsCounter != 0) {
// This is a digit char, we must localize it.
digitsBuffer[cursor] += fastPathData.zeroDelta;
digitsCounter--;
} else {
// Decimal separator or grouping char. Reinit counter only.
digitsCounter = groupingSize;
}
}
} /**
* This is the main entry point for the fast-path format algorithm.
*
* At this point we are sure to be in the expected conditions to run it.
* This algorithm builds the formatted result and puts it in the dedicated
* {@code fastPathData.fastPathContainer}.
*
* @param d the double value to be formatted.
* @param negative Flag precising if {@code d} is negative.
*/
private void fastDoubleFormat(double d,
boolean negative) { char[] container = fastPathData.fastPathContainer; /*
* The principle of the algorithm is to :
* - Break the passed double into its integral and fractional parts
* converted into integers.
* - Then decide if rounding up must be applied or not by following
* the half-even rounding rule, first using approximated scaled
* fractional part.
* - For the difficult cases (approximated scaled fractional part
* being exactly 0.5d), we refine the rounding decision by calling
* exactRoundUp utility method that both calculates the exact roundoff
* on the approximation and takes correct rounding decision.
* - We round-up the fractional part if needed, possibly propagating the
* rounding to integral part if we meet a "all-nine" case for the
* scaled fractional part.
* - We then collect digits from the resulting integral and fractional
* parts, also setting the required grouping chars on the fly.
* - Then we localize the collected digits if needed, and
* - Finally prepend/append prefix/suffix if any is needed.
*/ // Exact integral part of d.
int integralPartAsInt = (int) d; // Exact fractional part of d (since we subtract it's integral part).
double exactFractionalPart = d - (double) integralPartAsInt; // Approximated scaled fractional part of d (due to multiplication).
double scaledFractional =
exactFractionalPart * fastPathData.fractionalScaleFactor; // Exact integral part of scaled fractional above.
int fractionalPartAsInt = (int) scaledFractional; // Exact fractional part of scaled fractional above.
scaledFractional = scaledFractional - (double) fractionalPartAsInt; // Only when scaledFractional is exactly 0.5d do we have to do exact
// calculations and take fine-grained rounding decision, since
// approximated results above may lead to incorrect decision.
// Otherwise comparing against 0.5d (strictly greater or less) is ok.
boolean roundItUp = false;
if (scaledFractional >= 0.5d) {
if (scaledFractional == 0.5d)
// Rounding need fine-grained decision.
roundItUp = exactRoundUp(exactFractionalPart, fractionalPartAsInt);
else
roundItUp = true; if (roundItUp) {
// Rounds up both fractional part (and also integral if needed).
if (fractionalPartAsInt < fastPathData.fractionalMaxIntBound) {
fractionalPartAsInt++;
} else {
// Propagates rounding to integral part since "all nines" case.
fractionalPartAsInt = 0;
integralPartAsInt++;
}
}
} // Collecting digits.
collectFractionalDigits(fractionalPartAsInt, container,
fastPathData.fractionalFirstIndex);
collectIntegralDigits(integralPartAsInt, container,
fastPathData.integralLastIndex); // Localizing digits.
if (fastPathData.zeroDelta != 0)
localizeDigits(container); // Adding prefix and suffix.
if (negative) {
if (fastPathData.negativeAffixesRequired)
addAffixes(container,
fastPathData.charsNegativePrefix,
fastPathData.charsNegativeSuffix);
} else if (fastPathData.positiveAffixesRequired)
addAffixes(container,
fastPathData.charsPositivePrefix,
fastPathData.charsPositiveSuffix);
} /**
* A fast-path shortcut of format(double) to be called by NumberFormat, or by
* format(double, ...) public methods.
*
* If instance can be applied fast-path and passed double is not NaN or
* Infinity, is in the integer range, we call {@code fastDoubleFormat}
* after changing {@code d} to its positive value if necessary.
*
* Otherwise returns null by convention since fast-path can't be exercized.
*
* @param d The double value to be formatted
*
* @return the formatted result for {@code d} as a string.
*/
String fastFormat(double d) {
boolean isDataSet = false;
// (Re-)Evaluates fast-path status if needed.
if (fastPathCheckNeeded) {
isDataSet = checkAndSetFastPathStatus();
} if (!isFastPath )
// DecimalFormat instance is not in a fast-path state.
return null; if (!Double.isFinite(d))
// Should not use fast-path for Infinity and NaN.
return null; // Extracts and records sign of double value, possibly changing it
// to a positive one, before calling fastDoubleFormat().
boolean negative = false;
if (d < 0.0d) {
negative = true;
d = -d;
} else if (d == 0.0d) {
negative = (Math.copySign(1.0d, d) == -1.0d);
d = +0.0d;
} if (d > MAX_INT_AS_DOUBLE)
// Filters out values that are outside expected fast-path range
return null;
else {
if (!isDataSet) {
/*
* If the fast path data is not set through
* checkAndSetFastPathStatus() and fulfil the
* fast path conditions then reset the data
* directly through resetFastPathData()
*/
resetFastPathData(isFastPath);
}
fastDoubleFormat(d, negative); } // Returns a new string from updated fastPathContainer.
return new String(fastPathData.fastPathContainer,
fastPathData.firstUsedIndex,
fastPathData.lastFreeIndex - fastPathData.firstUsedIndex); } // ======== End fast-path formating logic for double ========================= /**
* Complete the formatting of a finite number. On entry, the digitList must
* be filled in with the correct digits.
*/
private StringBuffer subformat(StringBuffer result, FieldDelegate delegate,
boolean isNegative, boolean isInteger,
int maxIntDigits, int minIntDigits,
int maxFraDigits, int minFraDigits) {
// NOTE: This isn't required anymore because DigitList takes care of this.
//
// // The negative of the exponent represents the number of leading
// // zeros between the decimal and the first non-zero digit, for
// // a value < 0.1 (e.g., for 0.00123, -fExponent == 2). If this
// // is more than the maximum fraction digits, then we have an underflow
// // for the printed representation. We recognize this here and set
// // the DigitList representation to zero in this situation.
//
// if (-digitList.decimalAt >= getMaximumFractionDigits())
// {
// digitList.count = 0;
// } char zero = symbols.getZeroDigit();
int zeroDelta = zero - '0'; // '0' is the DigitList representation of zero
char grouping = symbols.getGroupingSeparator();
char decimal = isCurrencyFormat ?
symbols.getMonetaryDecimalSeparator() :
symbols.getDecimalSeparator(); /* Per bug 4147706, DecimalFormat must respect the sign of numbers which
* format as zero. This allows sensible computations and preserves
* relations such as signum(1/x) = signum(x), where x is +Infinity or
* -Infinity. Prior to this fix, we always formatted zero values as if
* they were positive. Liu 7/6/98.
*/
if (digitList.isZero()) {
digitList.decimalAt = 0; // Normalize
} if (isNegative) {
append(result, negativePrefix, delegate,
getNegativePrefixFieldPositions(), Field.SIGN);
} else {
append(result, positivePrefix, delegate,
getPositivePrefixFieldPositions(), Field.SIGN);
} if (useExponentialNotation) {
int iFieldStart = result.length();
int iFieldEnd = -1;
int fFieldStart = -1; // Minimum integer digits are handled in exponential format by
// adjusting the exponent. For example, 0.01234 with 3 minimum
// integer digits is "123.4E-4". // Maximum integer digits are interpreted as indicating the
// repeating range. This is useful for engineering notation, in
// which the exponent is restricted to a multiple of 3. For
// example, 0.01234 with 3 maximum integer digits is "12.34e-3".
// If maximum integer digits are > 1 and are larger than
// minimum integer digits, then minimum integer digits are
// ignored.
int exponent = digitList.decimalAt;
int repeat = maxIntDigits;
int minimumIntegerDigits = minIntDigits;
if (repeat > 1 && repeat > minIntDigits) {
// 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.
if (exponent >= 1) {
exponent = ((exponent - 1) / repeat) * repeat;
} else {
// integer division rounds towards 0
exponent = ((exponent - repeat) / repeat) * repeat;
}
minimumIntegerDigits = 1;
} else {
// No repeating range is defined; use minimum integer digits.
exponent -= minimumIntegerDigits;
} // We now output a minimum number of digits, and more if there
// are more digits, up to the maximum number of digits. We
// place the decimal point after the "integer" digits, which
// are the first (decimalAt - exponent) digits.
int minimumDigits = minIntDigits + minFraDigits;
if (minimumDigits < 0) { // overflow?
minimumDigits = Integer.MAX_VALUE;
} // The number of integer digits is handled specially if the number
// is zero, since then there may be no digits.
int integerDigits = digitList.isZero() ? minimumIntegerDigits :
digitList.decimalAt - exponent;
if (minimumDigits < integerDigits) {
minimumDigits = integerDigits;
}
int totalDigits = digitList.count;
if (minimumDigits > totalDigits) {
totalDigits = minimumDigits;
}
boolean addedDecimalSeparator = false; for (int i=0; i<totalDigits; ++i) {
if (i == integerDigits) {
// Record field information for caller.
iFieldEnd = result.length(); result.append(decimal);
addedDecimalSeparator = true; // Record field information for caller.
fFieldStart = result.length();
}
result.append((i < digitList.count) ?
(char)(digitList.digits[i] + zeroDelta) :
zero);
} if (decimalSeparatorAlwaysShown && totalDigits == integerDigits) {
// Record field information for caller.
iFieldEnd = result.length(); result.append(decimal);
addedDecimalSeparator = true; // Record field information for caller.
fFieldStart = result.length();
} // Record field information
if (iFieldEnd == -1) {
iFieldEnd = result.length();
}
delegate.formatted(INTEGER_FIELD, Field.INTEGER, Field.INTEGER,
iFieldStart, iFieldEnd, result);
if (addedDecimalSeparator) {
delegate.formatted(Field.DECIMAL_SEPARATOR,
Field.DECIMAL_SEPARATOR,
iFieldEnd, fFieldStart, result);
}
if (fFieldStart == -1) {
fFieldStart = result.length();
}
delegate.formatted(FRACTION_FIELD, Field.FRACTION, Field.FRACTION,
fFieldStart, result.length(), result); // The exponent is output using the pattern-specified minimum
// exponent digits. There is no maximum limit to the exponent
// digits, since truncating the exponent would result in an
// unacceptable inaccuracy.
int fieldStart = result.length(); result.append(symbols.getExponentSeparator()); delegate.formatted(Field.EXPONENT_SYMBOL, Field.EXPONENT_SYMBOL,
fieldStart, result.length(), result); // For zero values, we force the exponent to zero. We
// must do this here, and not earlier, because the value
// is used to determine integer digit count above.
if (digitList.isZero()) {
exponent = 0;
} boolean negativeExponent = exponent < 0;
if (negativeExponent) {
exponent = -exponent;
fieldStart = result.length();
result.append(symbols.getMinusSign());
delegate.formatted(Field.EXPONENT_SIGN, Field.EXPONENT_SIGN,
fieldStart, result.length(), result);
}
digitList.set(negativeExponent, exponent); int eFieldStart = result.length(); for (int i=digitList.decimalAt; i<minExponentDigits; ++i) {
result.append(zero);
}
for (int i=0; i<digitList.decimalAt; ++i) {
result.append((i < digitList.count) ?
(char)(digitList.digits[i] + zeroDelta) : zero);
}
delegate.formatted(Field.EXPONENT, Field.EXPONENT, eFieldStart,
result.length(), result);
} else {
int iFieldStart = result.length(); // Output the integer portion. Here 'count' is the total
// number of integer digits we will display, including both
// leading zeros required to satisfy getMinimumIntegerDigits,
// and actual digits present in the number.
int count = minIntDigits;
int digitIndex = 0; // Index into digitList.fDigits[]
if (digitList.decimalAt > 0 && count < digitList.decimalAt) {
count = digitList.decimalAt;
} // Handle the case where getMaximumIntegerDigits() is smaller
// than the real number of integer digits. If this is so, we
// output the least significant max integer digits. For example,
// the value 1997 printed with 2 max integer digits is just "97".
if (count > maxIntDigits) {
count = maxIntDigits;
digitIndex = digitList.decimalAt - count;
} int sizeBeforeIntegerPart = result.length();
for (int i=count-1; i>=0; --i) {
if (i < digitList.decimalAt && digitIndex < digitList.count) {
// Output a real digit
result.append((char)(digitList.digits[digitIndex++] + zeroDelta));
} else {
// Output a leading zero
result.append(zero);
} // Output grouping separator if necessary. Don't output a
// grouping separator if i==0 though; that's at the end of
// the integer part.
if (isGroupingUsed() && i>0 && (groupingSize != 0) &&
(i % groupingSize == 0)) {
int gStart = result.length();
result.append(grouping);
delegate.formatted(Field.GROUPING_SEPARATOR,
Field.GROUPING_SEPARATOR, gStart,
result.length(), result);
}
} // Determine whether or not there are any printable fractional
// digits. If we've used up the digits we know there aren't.
boolean fractionPresent = (minFraDigits > 0) ||
(!isInteger && digitIndex < digitList.count); // If there is no fraction present, and we haven't printed any
// integer digits, then print a zero. Otherwise we won't print
// _any_ digits, and we won't be able to parse this string.
if (!fractionPresent && result.length() == sizeBeforeIntegerPart) {
result.append(zero);
} delegate.formatted(INTEGER_FIELD, Field.INTEGER, Field.INTEGER,
iFieldStart, result.length(), result); // Output the decimal separator if we always do so.
int sStart = result.length();
if (decimalSeparatorAlwaysShown || fractionPresent) {
result.append(decimal);
} if (sStart != result.length()) {
delegate.formatted(Field.DECIMAL_SEPARATOR,
Field.DECIMAL_SEPARATOR,
sStart, result.length(), result);
}
int fFieldStart = result.length(); for (int i=0; i < maxFraDigits; ++i) {
// Here is where we escape from the loop. We escape if we've
// output the maximum fraction digits (specified in the for
// expression above).
// We also stop when we've output the minimum digits and either:
// we have an integer, so there is no fractional stuff to
// display, or we're out of significant digits.
if (i >= minFraDigits &&
(isInteger || digitIndex >= digitList.count)) {
break;
} // Output leading fractional zeros. These are zeros that come
// after the decimal but before any significant digits. These
// are only output if abs(number being formatted) < 1.0.
if (-1-i > (digitList.decimalAt-1)) {
result.append(zero);
continue;
} // Output a digit, if we have any precision left, or a
// zero if we don't. We don't want to output noise digits.
if (!isInteger && digitIndex < digitList.count) {
result.append((char)(digitList.digits[digitIndex++] + zeroDelta));
} else {
result.append(zero);
}
} // Record field information for caller.
delegate.formatted(FRACTION_FIELD, Field.FRACTION, Field.FRACTION,
fFieldStart, result.length(), result);
} if (isNegative) {
append(result, negativeSuffix, delegate,
getNegativeSuffixFieldPositions(), Field.SIGN);
} else {
append(result, positiveSuffix, delegate,
getPositiveSuffixFieldPositions(), Field.SIGN);
} return result;
} /**
* Appends the String <code>string</code> to <code>result</code>.
* <code>delegate</code> is notified of all the
* <code>FieldPosition</code>s in <code>positions</code>.
* <p>
* If one of the <code>FieldPosition</code>s in <code>positions</code>
* identifies a <code>SIGN</code> attribute, it is mapped to
* <code>signAttribute</code>. This is used
* to map the <code>SIGN</code> attribute to the <code>EXPONENT</code>
* attribute as necessary.
* <p>
* This is used by <code>subformat</code> to add the prefix/suffix.
*/
private void append(StringBuffer result, String string,
FieldDelegate delegate,
FieldPosition[] positions,
Format.Field signAttribute) {
int start = result.length(); if (string.length() > 0) {
result.append(string);
for (int counter = 0, max = positions.length; counter < max;
counter++) {
FieldPosition fp = positions[counter];
Format.Field attribute = fp.getFieldAttribute(); if (attribute == Field.SIGN) {
attribute = signAttribute;
}
delegate.formatted(attribute, attribute,
start + fp.getBeginIndex(),
start + fp.getEndIndex(), result);
}
}
} /**
* Parses text from a string to produce a <code>Number</code>.
* <p>
* The method attempts to parse text starting at the index given by
* <code>pos</code>.
* 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, the error index of <code>pos</code> is set to the index of
* the character where the error occurred, and null is returned.
* <p>
* The subclass returned depends on the value of {@link #isParseBigDecimal}
* as well as on the string being parsed.
* <ul>
* <li>If <code>isParseBigDecimal()</code> is false (the default),
* most integer values are returned as <code>Long</code>
* objects, no matter how they are written: <code>"17"</code> and
* <code>"17.000"</code> both parse to <code>Long(17)</code>.
* Values that cannot fit into a <code>Long</code> are returned as
* <code>Double</code>s. This includes values with a fractional part,
* infinite values, <code>NaN</code>, and the value -0.0.
* <code>DecimalFormat</code> does <em>not</em> decide whether to
* return a <code>Double</code> or a <code>Long</code> based on the
* presence of a decimal separator in the source string. Doing so
* would prevent integers that overflow the mantissa of a double,
* such as <code>"-9,223,372,036,854,775,808.00"</code>, from being
* parsed accurately.
* <p>
* Callers may use the <code>Number</code> methods
* <code>doubleValue</code>, <code>longValue</code>, etc., to obtain
* the type they want.
* <li>If <code>isParseBigDecimal()</code> is true, values are returned
* as <code>BigDecimal</code> objects. The values are the ones
* constructed by {@link java.math.BigDecimal#BigDecimal(String)}
* for corresponding strings in locale-independent format. The
* special cases negative and positive infinity and NaN are returned
* as <code>Double</code> instances holding the values of the
* corresponding <code>Double</code> constants.
* </ul>
* <p>
* <code>DecimalFormat</code> parses all Unicode characters that represent
* decimal digits, as defined by <code>Character.digit()</code>. In
* addition, <code>DecimalFormat</code> also recognizes as digits the ten
* consecutive characters starting with the localized zero digit defined in
* the <code>DecimalFormatSymbols</code> object.
*
* @param text the string to be parsed
* @param pos A <code>ParsePosition</code> object with index and error
* index information as described above.
* @return the parsed value, or <code>null</code> if the parse fails
* @exception NullPointerException if <code>text</code> or
* <code>pos</code> is null.
*/
@Override
public Number parse(String text, ParsePosition pos) {
// special case NaN
if (text.regionMatches(pos.index, symbols.getNaN(), 0, symbols.getNaN().length())) {
pos.index = pos.index + symbols.getNaN().length();
return Double.valueOf(Double.NaN);
} boolean[] status = new boolean[STATUS_LENGTH];
if (!subparse(text, pos, positivePrefix, negativePrefix, digitList, false, status)) {
return null;
} // special case INFINITY
if (status[STATUS_INFINITE]) {
if (status[STATUS_POSITIVE] == (multiplier >= 0)) {
return Double.valueOf(Double.POSITIVE_INFINITY);
} else {
return Double.valueOf(Double.NEGATIVE_INFINITY);
}
} if (multiplier == 0) {
if (digitList.isZero()) {
return Double.valueOf(Double.NaN);
} else if (status[STATUS_POSITIVE]) {
return Double.valueOf(Double.POSITIVE_INFINITY);
} else {
return Double.valueOf(Double.NEGATIVE_INFINITY);
}
} if (isParseBigDecimal()) {
BigDecimal bigDecimalResult = digitList.getBigDecimal(); if (multiplier != 1) {
try {
bigDecimalResult = bigDecimalResult.divide(getBigDecimalMultiplier());
}
catch (ArithmeticException e) { // non-terminating decimal expansion
bigDecimalResult = bigDecimalResult.divide(getBigDecimalMultiplier(), roundingMode);
}
} if (!status[STATUS_POSITIVE]) {
bigDecimalResult = bigDecimalResult.negate();
}
return bigDecimalResult;
} else {
boolean gotDouble = true;
boolean gotLongMinimum = false;
double doubleResult = 0.0;
long longResult = 0; // Finally, have DigitList parse the digits into a value.
if (digitList.fitsIntoLong(status[STATUS_POSITIVE], isParseIntegerOnly())) {
gotDouble = false;
longResult = digitList.getLong();
if (longResult < 0) { // got Long.MIN_VALUE
gotLongMinimum = true;
}
} else {
doubleResult = digitList.getDouble();
} // Divide by multiplier. We have to be careful here not to do
// unneeded conversions between double and long.
if (multiplier != 1) {
if (gotDouble) {
doubleResult /= multiplier;
} else {
// Avoid converting to double if we can
if (longResult % multiplier == 0) {
longResult /= multiplier;
} else {
doubleResult = ((double)longResult) / multiplier;
gotDouble = true;
}
}
} if (!status[STATUS_POSITIVE] && !gotLongMinimum) {
doubleResult = -doubleResult;
longResult = -longResult;
} // At this point, if we divided the result by the multiplier, the
// result may fit into a long. We check for this case and return
// a long if possible.
// We must do this AFTER applying the negative (if appropriate)
// in order to handle the case of LONG_MIN; otherwise, if we do
// this with a positive value -LONG_MIN, the double is > 0, but
// the long is < 0. We also must retain a double in the case of
// -0.0, which will compare as == to a long 0 cast to a double
// (bug 4162852).
if (multiplier != 1 && gotDouble) {
longResult = (long)doubleResult;
gotDouble = ((doubleResult != (double)longResult) ||
(doubleResult == 0.0 && 1/doubleResult < 0.0)) &&
!isParseIntegerOnly();
} // cast inside of ?: because of binary numeric promotion, JLS 15.25
return gotDouble ? (Number)doubleResult : (Number)longResult;
}
} /**
* Return a BigInteger multiplier.
*/
private BigInteger getBigIntegerMultiplier() {
if (bigIntegerMultiplier == null) {
bigIntegerMultiplier = BigInteger.valueOf(multiplier);
}
return bigIntegerMultiplier;
}
private transient BigInteger bigIntegerMultiplier; /**
* Return a BigDecimal multiplier.
*/
private BigDecimal getBigDecimalMultiplier() {
if (bigDecimalMultiplier == null) {
bigDecimalMultiplier = new BigDecimal(multiplier);
}
return bigDecimalMultiplier;
}
private transient BigDecimal bigDecimalMultiplier; private static final int STATUS_INFINITE = 0;
private static final int STATUS_POSITIVE = 1;
private static final int STATUS_LENGTH = 2; /**
* Parse the given text into a number. The text is parsed beginning at
* parsePosition, until an unparseable character is seen.
* @param text The string to parse.
* @param parsePosition The position at which to being parsing. Upon
* return, the first unparseable character.
* @param digits The DigitList to set to the parsed value.
* @param isExponent If true, parse an exponent. This means no
* infinite values and integer only.
* @param status Upon return contains boolean status flags indicating
* whether the value was infinite and whether it was positive.
*/
private final boolean subparse(String text, ParsePosition parsePosition,
String positivePrefix, String negativePrefix,
DigitList digits, boolean isExponent,
boolean status[]) {
int position = parsePosition.index;
int oldStart = parsePosition.index;
int backup;
boolean gotPositive, gotNegative; // check for positivePrefix; take longest
gotPositive = text.regionMatches(position, positivePrefix, 0,
positivePrefix.length());
gotNegative = text.regionMatches(position, negativePrefix, 0,
negativePrefix.length()); if (gotPositive && gotNegative) {
if (positivePrefix.length() > negativePrefix.length()) {
gotNegative = false;
} else if (positivePrefix.length() < negativePrefix.length()) {
gotPositive = false;
}
} if (gotPositive) {
position += positivePrefix.length();
} else if (gotNegative) {
position += negativePrefix.length();
} else {
parsePosition.errorIndex = position;
return false;
} // process digits or Inf, find decimal position
status[STATUS_INFINITE] = false;
if (!isExponent && text.regionMatches(position,symbols.getInfinity(),0,
symbols.getInfinity().length())) {
position += symbols.getInfinity().length();
status[STATUS_INFINITE] = true;
} else {
// We now have a string of digits, possibly with grouping symbols,
// and decimal points. We want to process these into a DigitList.
// We don't want to put a bunch of leading zeros into the DigitList
// though, so we keep track of the location of the decimal point,
// put only significant digits into the DigitList, and adjust the
// exponent as needed. digits.decimalAt = digits.count = 0;
char zero = symbols.getZeroDigit();
char decimal = isCurrencyFormat ?
symbols.getMonetaryDecimalSeparator() :
symbols.getDecimalSeparator();
char grouping = symbols.getGroupingSeparator();
String exponentString = symbols.getExponentSeparator();
boolean sawDecimal = false;
boolean sawExponent = false;
boolean sawDigit = false;
int exponent = 0; // Set to the exponent value, if any // We have to track digitCount ourselves, because digits.count will
// pin when the maximum allowable digits is reached.
int digitCount = 0; backup = -1;
for (; position < text.length(); ++position) {
char ch = text.charAt(position); /* We recognize all digit ranges, not only the Latin digit range
* '0'..'9'. We do so by using the Character.digit() method,
* which converts a valid Unicode digit to the range 0..9.
*
* The character 'ch' may be a digit. If so, place its value
* from 0 to 9 in 'digit'. First try using the locale digit,
* which may or MAY NOT be a standard Unicode digit range. If
* this fails, try using the standard Unicode digit ranges by
* calling Character.digit(). If this also fails, digit will
* have a value outside the range 0..9.
*/
int digit = ch - zero;
if (digit < 0 || digit > 9) {
digit = Character.digit(ch, 10);
} if (digit == 0) {
// Cancel out backup setting (see grouping handler below)
backup = -1; // Do this BEFORE continue statement below!!!
sawDigit = true; // Handle leading zeros
if (digits.count == 0) {
// Ignore leading zeros in integer part of number.
if (!sawDecimal) {
continue;
} // If we have seen the decimal, but no significant
// digits yet, then we account for leading zeros by
// decrementing the digits.decimalAt into negative
// values.
--digits.decimalAt;
} else {
++digitCount;
digits.append((char)(digit + '0'));
}
} else if (digit > 0 && digit <= 9) { // [sic] digit==0 handled above
sawDigit = true;
++digitCount;
digits.append((char)(digit + '0')); // Cancel out backup setting (see grouping handler below)
backup = -1;
} else if (!isExponent && ch == decimal) {
// If we're only parsing integers, or if we ALREADY saw the
// decimal, then don't parse this one.
if (isParseIntegerOnly() || sawDecimal) {
break;
}
digits.decimalAt = digitCount; // Not digits.count!
sawDecimal = true;
} else if (!isExponent && ch == grouping && isGroupingUsed()) {
if (sawDecimal) {
break;
}
// Ignore grouping characters, if we are using them, but
// require that they be followed by a digit. Otherwise
// we backup and reprocess them.
backup = position;
} else if (!isExponent && text.regionMatches(position, exponentString, 0, exponentString.length())
&& !sawExponent) {
// Process the exponent by recursively calling this method.
ParsePosition pos = new ParsePosition(position + exponentString.length());
boolean[] stat = new boolean[STATUS_LENGTH];
DigitList exponentDigits = new DigitList(); if (subparse(text, pos, "", Character.toString(symbols.getMinusSign()), exponentDigits, true, stat) &&
exponentDigits.fitsIntoLong(stat[STATUS_POSITIVE], true)) {
position = pos.index; // Advance past the exponent
exponent = (int)exponentDigits.getLong();
if (!stat[STATUS_POSITIVE]) {
exponent = -exponent;
}
sawExponent = true;
}
break; // Whether we fail or succeed, we exit this loop
} else {
break;
}
} if (backup != -1) {
position = backup;
} // If there was no decimal point we have an integer
if (!sawDecimal) {
digits.decimalAt = digitCount; // Not digits.count!
} // Adjust for exponent, if any
digits.decimalAt += exponent; // If none of the text string was recognized. For example, parse
// "x" with pattern "#0.00" (return index and error index both 0)
// parse "$" with pattern "$#0.00". (return index 0 and error
// index 1).
if (!sawDigit && digitCount == 0) {
parsePosition.index = oldStart;
parsePosition.errorIndex = oldStart;
return false;
}
} // check for suffix
if (!isExponent) {
if (gotPositive) {
gotPositive = text.regionMatches(position,positiveSuffix,0,
positiveSuffix.length());
}
if (gotNegative) {
gotNegative = text.regionMatches(position,negativeSuffix,0,
negativeSuffix.length());
} // if both match, take longest
if (gotPositive && gotNegative) {
if (positiveSuffix.length() > negativeSuffix.length()) {
gotNegative = false;
} else if (positiveSuffix.length() < negativeSuffix.length()) {
gotPositive = false;
}
} // fail if neither or both
if (gotPositive == gotNegative) {
parsePosition.errorIndex = position;
return false;
} parsePosition.index = position +
(gotPositive ? positiveSuffix.length() : negativeSuffix.length()); // mark success!
} else {
parsePosition.index = position;
} status[STATUS_POSITIVE] = gotPositive;
if (parsePosition.index == oldStart) {
parsePosition.errorIndex = position;
return false;
}
return true;
} /**
* Returns a copy of the decimal format symbols, which is generally not
* changed by the programmer or user.
* @return a copy of the desired DecimalFormatSymbols
* @see java.text.DecimalFormatSymbols
*/
public DecimalFormatSymbols getDecimalFormatSymbols() {
try {
// don't allow multiple references
return (DecimalFormatSymbols) symbols.clone();
} catch (Exception foo) {
return null; // should never happen
}
} /**
* Sets the decimal format symbols, which is generally not changed
* by the programmer or user.
* @param newSymbols desired DecimalFormatSymbols
* @see java.text.DecimalFormatSymbols
*/
public void setDecimalFormatSymbols(DecimalFormatSymbols newSymbols) {
try {
// don't allow multiple references
symbols = (DecimalFormatSymbols) newSymbols.clone();
expandAffixes();
fastPathCheckNeeded = true;
} catch (Exception foo) {
// should never happen
}
} /**
* Get the positive prefix.
* <P>Examples: +123, $123, sFr123
*
* @return the positive prefix
*/
public String getPositivePrefix () {
return positivePrefix;
} /**
* Set the positive prefix.
* <P>Examples: +123, $123, sFr123
*
* @param newValue the new positive prefix
*/
public void setPositivePrefix (String newValue) {
positivePrefix = newValue;
posPrefixPattern = null;
positivePrefixFieldPositions = null;
fastPathCheckNeeded = true;
} /**
* Returns the FieldPositions of the fields in the prefix used for
* positive numbers. This is not used if the user has explicitly set
* a positive prefix via <code>setPositivePrefix</code>. This is
* lazily created.
*
* @return FieldPositions in positive prefix
*/
private FieldPosition[] getPositivePrefixFieldPositions() {
if (positivePrefixFieldPositions == null) {
if (posPrefixPattern != null) {
positivePrefixFieldPositions = expandAffix(posPrefixPattern);
} else {
positivePrefixFieldPositions = EmptyFieldPositionArray;
}
}
return positivePrefixFieldPositions;
} /**
* Get the negative prefix.
* <P>Examples: -123, ($123) (with negative suffix), sFr-123
*
* @return the negative prefix
*/
public String getNegativePrefix () {
return negativePrefix;
} /**
* Set the negative prefix.
* <P>Examples: -123, ($123) (with negative suffix), sFr-123
*
* @param newValue the new negative prefix
*/
public void setNegativePrefix (String newValue) {
negativePrefix = newValue;
negPrefixPattern = null;
fastPathCheckNeeded = true;
} /**
* Returns the FieldPositions of the fields in the prefix used for
* negative numbers. This is not used if the user has explicitly set
* a negative prefix via <code>setNegativePrefix</code>. This is
* lazily created.
*
* @return FieldPositions in positive prefix
*/
private FieldPosition[] getNegativePrefixFieldPositions() {
if (negativePrefixFieldPositions == null) {
if (negPrefixPattern != null) {
negativePrefixFieldPositions = expandAffix(negPrefixPattern);
} else {
negativePrefixFieldPositions = EmptyFieldPositionArray;
}
}
return negativePrefixFieldPositions;
} /**
* Get the positive suffix.
* <P>Example: 123%
*
* @return the positive suffix
*/
public String getPositiveSuffix () {
return positiveSuffix;
} /**
* Set the positive suffix.
* <P>Example: 123%
*
* @param newValue the new positive suffix
*/
public void setPositiveSuffix (String newValue) {
positiveSuffix = newValue;
posSuffixPattern = null;
fastPathCheckNeeded = true;
} /**
* Returns the FieldPositions of the fields in the suffix used for
* positive numbers. This is not used if the user has explicitly set
* a positive suffix via <code>setPositiveSuffix</code>. This is
* lazily created.
*
* @return FieldPositions in positive prefix
*/
private FieldPosition[] getPositiveSuffixFieldPositions() {
if (positiveSuffixFieldPositions == null) {
if (posSuffixPattern != null) {
positiveSuffixFieldPositions = expandAffix(posSuffixPattern);
} else {
positiveSuffixFieldPositions = EmptyFieldPositionArray;
}
}
return positiveSuffixFieldPositions;
} /**
* Get the negative suffix.
* <P>Examples: -123%, ($123) (with positive suffixes)
*
* @return the negative suffix
*/
public String getNegativeSuffix () {
return negativeSuffix;
} /**
* Set the negative suffix.
* <P>Examples: 123%
*
* @param newValue the new negative suffix
*/
public void setNegativeSuffix (String newValue) {
negativeSuffix = newValue;
negSuffixPattern = null;
fastPathCheckNeeded = true;
} /**
* Returns the FieldPositions of the fields in the suffix used for
* negative numbers. This is not used if the user has explicitly set
* a negative suffix via <code>setNegativeSuffix</code>. This is
* lazily created.
*
* @return FieldPositions in positive prefix
*/
private FieldPosition[] getNegativeSuffixFieldPositions() {
if (negativeSuffixFieldPositions == null) {
if (negSuffixPattern != null) {
negativeSuffixFieldPositions = expandAffix(negSuffixPattern);
} else {
negativeSuffixFieldPositions = EmptyFieldPositionArray;
}
}
return negativeSuffixFieldPositions;
} /**
* Gets the multiplier for use in percent, per mille, and similar
* formats.
*
* @return the multiplier
* @see #setMultiplier(int)
*/
public int getMultiplier () {
return multiplier;
} /**
* Sets the multiplier for use in percent, per mille, and similar
* formats.
* For a percent format, set the multiplier to 100 and the suffixes to
* have '%' (for Arabic, use the Arabic percent sign).
* For a per mille format, set the multiplier to 1000 and the suffixes to
* have '\u2030'.
*
* <P>Example: with multiplier 100, 1.23 is formatted as "123", and
* "123" is parsed into 1.23.
*
* @param newValue the new multiplier
* @see #getMultiplier
*/
public void setMultiplier (int newValue) {
multiplier = newValue;
bigDecimalMultiplier = null;
bigIntegerMultiplier = null;
fastPathCheckNeeded = true;
} /**
* {@inheritDoc}
*/
@Override
public void setGroupingUsed(boolean newValue) {
super.setGroupingUsed(newValue);
fastPathCheckNeeded = true;
} /**
* Return the grouping size. Grouping size is the number of digits between
* grouping separators in the integer portion of a number. For example,
* in the number "123,456.78", the grouping size is 3.
*
* @return the grouping size
* @see #setGroupingSize
* @see java.text.NumberFormat#isGroupingUsed
* @see java.text.DecimalFormatSymbols#getGroupingSeparator
*/
public int getGroupingSize () {
return groupingSize;
} /**
* Set the grouping size. Grouping size is the number of digits between
* grouping separators in the integer portion of a number. For example,
* in the number "123,456.78", the grouping size is 3.
* <br>
* The value passed in is converted to a byte, which may lose information.
*
* @param newValue the new grouping size
* @see #getGroupingSize
* @see java.text.NumberFormat#setGroupingUsed
* @see java.text.DecimalFormatSymbols#setGroupingSeparator
*/
public void setGroupingSize (int newValue) {
groupingSize = (byte)newValue;
fastPathCheckNeeded = true;
} /**
* Allows you to get the behavior of the decimal separator with integers.
* (The decimal separator will always appear with decimals.)
* <P>Example: Decimal ON: 12345 → 12345.; OFF: 12345 → 12345
*
* @return {@code true} if the decimal separator is always shown;
* {@code false} otherwise
*/
public boolean isDecimalSeparatorAlwaysShown() {
return decimalSeparatorAlwaysShown;
} /**
* Allows you to set the behavior of the decimal separator with integers.
* (The decimal separator will always appear with decimals.)
* <P>Example: Decimal ON: 12345 → 12345.; OFF: 12345 → 12345
*
* @param newValue {@code true} if the decimal separator is always shown;
* {@code false} otherwise
*/
public void setDecimalSeparatorAlwaysShown(boolean newValue) {
decimalSeparatorAlwaysShown = newValue;
fastPathCheckNeeded = true;
} /**
* Returns whether the {@link #parse(java.lang.String, java.text.ParsePosition)}
* method returns <code>BigDecimal</code>. The default value is false.
*
* @return {@code true} if the parse method returns BigDecimal;
* {@code false} otherwise
* @see #setParseBigDecimal
* @since 1.5
*/
public boolean isParseBigDecimal() {
return parseBigDecimal;
} /**
* Sets whether the {@link #parse(java.lang.String, java.text.ParsePosition)}
* method returns <code>BigDecimal</code>.
*
* @param newValue {@code true} if the parse method returns BigDecimal;
* {@code false} otherwise
* @see #isParseBigDecimal
* @since 1.5
*/
public void setParseBigDecimal(boolean newValue) {
parseBigDecimal = newValue;
} /**
* Standard override; no change in semantics.
*/
@Override
public Object clone() {
DecimalFormat other = (DecimalFormat) super.clone();
other.symbols = (DecimalFormatSymbols) symbols.clone();
other.digitList = (DigitList) digitList.clone(); // Fast-path is almost stateless algorithm. The only logical state is the
// isFastPath flag. In addition fastPathCheckNeeded is a sentinel flag
// that forces recalculation of all fast-path fields when set to true.
//
// There is thus no need to clone all the fast-path fields.
// We just only need to set fastPathCheckNeeded to true when cloning,
// and init fastPathData to null as if it were a truly new instance.
// Every fast-path field will be recalculated (only once) at next usage of
// fast-path algorithm.
other.fastPathCheckNeeded = true;
other.isFastPath = false;
other.fastPathData = null; return other;
} /**
* Overrides equals
*/
@Override
public boolean equals(Object obj)
{
if (obj == null)
return false;
if (!super.equals(obj))
return false; // super does class check
DecimalFormat other = (DecimalFormat) obj;
return ((posPrefixPattern == other.posPrefixPattern &&
positivePrefix.equals(other.positivePrefix))
|| (posPrefixPattern != null &&
posPrefixPattern.equals(other.posPrefixPattern)))
&& ((posSuffixPattern == other.posSuffixPattern &&
positiveSuffix.equals(other.positiveSuffix))
|| (posSuffixPattern != null &&
posSuffixPattern.equals(other.posSuffixPattern)))
&& ((negPrefixPattern == other.negPrefixPattern &&
negativePrefix.equals(other.negativePrefix))
|| (negPrefixPattern != null &&
negPrefixPattern.equals(other.negPrefixPattern)))
&& ((negSuffixPattern == other.negSuffixPattern &&
negativeSuffix.equals(other.negativeSuffix))
|| (negSuffixPattern != null &&
negSuffixPattern.equals(other.negSuffixPattern)))
&& multiplier == other.multiplier
&& groupingSize == other.groupingSize
&& decimalSeparatorAlwaysShown == other.decimalSeparatorAlwaysShown
&& parseBigDecimal == other.parseBigDecimal
&& useExponentialNotation == other.useExponentialNotation
&& (!useExponentialNotation ||
minExponentDigits == other.minExponentDigits)
&& maximumIntegerDigits == other.maximumIntegerDigits
&& minimumIntegerDigits == other.minimumIntegerDigits
&& maximumFractionDigits == other.maximumFractionDigits
&& minimumFractionDigits == other.minimumFractionDigits
&& roundingMode == other.roundingMode
&& symbols.equals(other.symbols);
} /**
* Overrides hashCode
*/
@Override
public int hashCode() {
return super.hashCode() * 37 + positivePrefix.hashCode();
// just enough fields for a reasonable distribution
} /**
* Synthesizes a pattern string that represents the current state
* of this Format object.
*
* @return a pattern string
* @see #applyPattern
*/
public String toPattern() {
return toPattern( false );
} /**
* Synthesizes a localized pattern string that represents the current
* state of this Format object.
*
* @return a localized pattern string
* @see #applyPattern
*/
public String toLocalizedPattern() {
return toPattern( true );
} /**
* Expand the affix pattern strings into the expanded affix strings. If any
* affix pattern string is null, do not expand it. This method should be
* called any time the symbols or the affix patterns change in order to keep
* the expanded affix strings up to date.
*/
private void expandAffixes() {
// Reuse one StringBuffer for better performance
StringBuffer buffer = new StringBuffer();
if (posPrefixPattern != null) {
positivePrefix = expandAffix(posPrefixPattern, buffer);
positivePrefixFieldPositions = null;
}
if (posSuffixPattern != null) {
positiveSuffix = expandAffix(posSuffixPattern, buffer);
positiveSuffixFieldPositions = null;
}
if (negPrefixPattern != null) {
negativePrefix = expandAffix(negPrefixPattern, buffer);
negativePrefixFieldPositions = null;
}
if (negSuffixPattern != null) {
negativeSuffix = expandAffix(negSuffixPattern, buffer);
negativeSuffixFieldPositions = null;
}
} /**
* Expand an affix pattern into an affix string. All characters in the
* pattern are literal unless prefixed by QUOTE. The following characters
* after QUOTE are recognized: PATTERN_PERCENT, PATTERN_PER_MILLE,
* PATTERN_MINUS, and CURRENCY_SIGN. If CURRENCY_SIGN is doubled (QUOTE +
* CURRENCY_SIGN + CURRENCY_SIGN), it is interpreted as an ISO 4217
* currency code. Any other character after a QUOTE represents itself.
* QUOTE must be followed by another character; QUOTE may not occur by
* itself at the end of the pattern.
*
* @param pattern the non-null, possibly empty pattern
* @param buffer a scratch StringBuffer; its contents will be lost
* @return the expanded equivalent of pattern
*/
private String expandAffix(String pattern, StringBuffer buffer) {
buffer.setLength(0);
for (int i=0; i<pattern.length(); ) {
char c = pattern.charAt(i++);
if (c == QUOTE) {
c = pattern.charAt(i++);
switch (c) {
case CURRENCY_SIGN:
if (i<pattern.length() &&
pattern.charAt(i) == CURRENCY_SIGN) {
++i;
buffer.append(symbols.getInternationalCurrencySymbol());
} else {
buffer.append(symbols.getCurrencySymbol());
}
continue;
case PATTERN_PERCENT:
c = symbols.getPercent();
break;
case PATTERN_PER_MILLE:
c = symbols.getPerMill();
break;
case PATTERN_MINUS:
c = symbols.getMinusSign();
break;
}
}
buffer.append(c);
}
return buffer.toString();
} /**
* Expand an affix pattern into an array of FieldPositions describing
* how the pattern would be expanded.
* All characters in the
* pattern are literal unless prefixed by QUOTE. The following characters
* after QUOTE are recognized: PATTERN_PERCENT, PATTERN_PER_MILLE,
* PATTERN_MINUS, and CURRENCY_SIGN. If CURRENCY_SIGN is doubled (QUOTE +
* CURRENCY_SIGN + CURRENCY_SIGN), it is interpreted as an ISO 4217
* currency code. Any other character after a QUOTE represents itself.
* QUOTE must be followed by another character; QUOTE may not occur by
* itself at the end of the pattern.
*
* @param pattern the non-null, possibly empty pattern
* @return FieldPosition array of the resulting fields.
*/
private FieldPosition[] expandAffix(String pattern) {
ArrayList<FieldPosition> positions = null;
int stringIndex = 0;
for (int i=0; i<pattern.length(); ) {
char c = pattern.charAt(i++);
if (c == QUOTE) {
int field = -1;
Format.Field fieldID = null;
c = pattern.charAt(i++);
switch (c) {
case CURRENCY_SIGN:
String string;
if (i<pattern.length() &&
pattern.charAt(i) == CURRENCY_SIGN) {
++i;
string = symbols.getInternationalCurrencySymbol();
} else {
string = symbols.getCurrencySymbol();
}
if (string.length() > 0) {
if (positions == null) {
positions = new ArrayList<>(2);
}
FieldPosition fp = new FieldPosition(Field.CURRENCY);
fp.setBeginIndex(stringIndex);
fp.setEndIndex(stringIndex + string.length());
positions.add(fp);
stringIndex += string.length();
}
continue;
case PATTERN_PERCENT:
c = symbols.getPercent();
field = -1;
fieldID = Field.PERCENT;
break;
case PATTERN_PER_MILLE:
c = symbols.getPerMill();
field = -1;
fieldID = Field.PERMILLE;
break;
case PATTERN_MINUS:
c = symbols.getMinusSign();
field = -1;
fieldID = Field.SIGN;
break;
}
if (fieldID != null) {
if (positions == null) {
positions = new ArrayList<>(2);
}
FieldPosition fp = new FieldPosition(fieldID, field);
fp.setBeginIndex(stringIndex);
fp.setEndIndex(stringIndex + 1);
positions.add(fp);
}
}
stringIndex++;
}
if (positions != null) {
return positions.toArray(EmptyFieldPositionArray);
}
return EmptyFieldPositionArray;
} /**
* Appends an affix pattern to the given StringBuffer, quoting special
* characters as needed. Uses the internal affix pattern, if that exists,
* or the literal affix, if the internal affix pattern is null. The
* appended string will generate the same affix pattern (or literal affix)
* when passed to toPattern().
*
* @param buffer the affix string is appended to this
* @param affixPattern a pattern such as posPrefixPattern; may be null
* @param expAffix a corresponding expanded affix, such as positivePrefix.
* Ignored unless affixPattern is null. If affixPattern is null, then
* expAffix is appended as a literal affix.
* @param localized true if the appended pattern should contain localized
* pattern characters; otherwise, non-localized pattern chars are appended
*/
private void appendAffix(StringBuffer buffer, String affixPattern,
String expAffix, boolean localized) {
if (affixPattern == null) {
appendAffix(buffer, expAffix, localized);
} else {
int i;
for (int pos=0; pos<affixPattern.length(); pos=i) {
i = affixPattern.indexOf(QUOTE, pos);
if (i < 0) {
appendAffix(buffer, affixPattern.substring(pos), localized);
break;
}
if (i > pos) {
appendAffix(buffer, affixPattern.substring(pos, i), localized);
}
char c = affixPattern.charAt(++i);
++i;
if (c == QUOTE) {
buffer.append(c);
// Fall through and append another QUOTE below
} else if (c == CURRENCY_SIGN &&
i<affixPattern.length() &&
affixPattern.charAt(i) == CURRENCY_SIGN) {
++i;
buffer.append(c);
// Fall through and append another CURRENCY_SIGN below
} else if (localized) {
switch (c) {
case PATTERN_PERCENT:
c = symbols.getPercent();
break;
case PATTERN_PER_MILLE:
c = symbols.getPerMill();
break;
case PATTERN_MINUS:
c = symbols.getMinusSign();
break;
}
}
buffer.append(c);
}
}
} /**
* Append an affix to the given StringBuffer, using quotes if
* there are special characters. Single quotes themselves must be
* escaped in either case.
*/
private void appendAffix(StringBuffer buffer, String affix, boolean localized) {
boolean needQuote;
if (localized) {
needQuote = affix.indexOf(symbols.getZeroDigit()) >= 0
|| affix.indexOf(symbols.getGroupingSeparator()) >= 0
|| affix.indexOf(symbols.getDecimalSeparator()) >= 0
|| affix.indexOf(symbols.getPercent()) >= 0
|| affix.indexOf(symbols.getPerMill()) >= 0
|| affix.indexOf(symbols.getDigit()) >= 0
|| affix.indexOf(symbols.getPatternSeparator()) >= 0
|| affix.indexOf(symbols.getMinusSign()) >= 0
|| affix.indexOf(CURRENCY_SIGN) >= 0;
} else {
needQuote = affix.indexOf(PATTERN_ZERO_DIGIT) >= 0
|| affix.indexOf(PATTERN_GROUPING_SEPARATOR) >= 0
|| affix.indexOf(PATTERN_DECIMAL_SEPARATOR) >= 0
|| affix.indexOf(PATTERN_PERCENT) >= 0
|| affix.indexOf(PATTERN_PER_MILLE) >= 0
|| affix.indexOf(PATTERN_DIGIT) >= 0
|| affix.indexOf(PATTERN_SEPARATOR) >= 0
|| affix.indexOf(PATTERN_MINUS) >= 0
|| affix.indexOf(CURRENCY_SIGN) >= 0;
}
if (needQuote) buffer.append('\'');
if (affix.indexOf('\'') < 0) buffer.append(affix);
else {
for (int j=0; j<affix.length(); ++j) {
char c = affix.charAt(j);
buffer.append(c);
if (c == '\'') buffer.append(c);
}
}
if (needQuote) buffer.append('\'');
} /**
* Does the real work of generating a pattern. */
private String toPattern(boolean localized) {
StringBuffer result = new StringBuffer();
for (int j = 1; j >= 0; --j) {
if (j == 1)
appendAffix(result, posPrefixPattern, positivePrefix, localized);
else appendAffix(result, negPrefixPattern, negativePrefix, localized);
int i;
int digitCount = useExponentialNotation
? getMaximumIntegerDigits()
: Math.max(groupingSize, getMinimumIntegerDigits())+1;
for (i = digitCount; i > 0; --i) {
if (i != digitCount && isGroupingUsed() && groupingSize != 0 &&
i % groupingSize == 0) {
result.append(localized ? symbols.getGroupingSeparator() :
PATTERN_GROUPING_SEPARATOR);
}
result.append(i <= getMinimumIntegerDigits()
? (localized ? symbols.getZeroDigit() : PATTERN_ZERO_DIGIT)
: (localized ? symbols.getDigit() : PATTERN_DIGIT));
}
if (getMaximumFractionDigits() > 0 || decimalSeparatorAlwaysShown)
result.append(localized ? symbols.getDecimalSeparator() :
PATTERN_DECIMAL_SEPARATOR);
for (i = 0; i < getMaximumFractionDigits(); ++i) {
if (i < getMinimumFractionDigits()) {
result.append(localized ? symbols.getZeroDigit() :
PATTERN_ZERO_DIGIT);
} else {
result.append(localized ? symbols.getDigit() :
PATTERN_DIGIT);
}
}
if (useExponentialNotation)
{
result.append(localized ? symbols.getExponentSeparator() :
PATTERN_EXPONENT);
for (i=0; i<minExponentDigits; ++i)
result.append(localized ? symbols.getZeroDigit() :
PATTERN_ZERO_DIGIT);
}
if (j == 1) {
appendAffix(result, posSuffixPattern, positiveSuffix, localized);
if ((negSuffixPattern == posSuffixPattern && // n == p == null
negativeSuffix.equals(positiveSuffix))
|| (negSuffixPattern != null &&
negSuffixPattern.equals(posSuffixPattern))) {
if ((negPrefixPattern != null && posPrefixPattern != null &&
negPrefixPattern.equals("'-" + posPrefixPattern)) ||
(negPrefixPattern == posPrefixPattern && // n == p == null
negativePrefix.equals(symbols.getMinusSign() + positivePrefix)))
break;
}
result.append(localized ? symbols.getPatternSeparator() :
PATTERN_SEPARATOR);
} else appendAffix(result, negSuffixPattern, negativeSuffix, localized);
}
return result.toString();
} /**
* Apply the given pattern to this Format object. A pattern is a
* short-hand specification for the various formatting properties.
* These properties can also be changed individually through the
* various setter methods.
* <p>
* There is no limit to integer digits set
* by this routine, since that is the typical end-user desire;
* use setMaximumInteger if you want to set a real value.
* For negative numbers, use a second pattern, separated by a semicolon
* <P>Example <code>"#,#00.0#"</code> → 1,234.56
* <P>This means a minimum of 2 integer digits, 1 fraction digit, and
* a maximum of 2 fraction digits.
* <p>Example: <code>"#,#00.0#;(#,#00.0#)"</code> for negatives in
* parentheses.
* <p>In negative patterns, the minimum and maximum counts are ignored;
* these are presumed to be set in the positive pattern.
*
* @param pattern a new pattern
* @exception NullPointerException if <code>pattern</code> is null
* @exception IllegalArgumentException if the given pattern is invalid.
*/
public void applyPattern(String pattern) {
applyPattern(pattern, false);
} /**
* Apply the given pattern to this Format object. The pattern
* is assumed to be in a localized notation. A pattern is a
* short-hand specification for the various formatting properties.
* These properties can also be changed individually through the
* various setter methods.
* <p>
* There is no limit to integer digits set
* by this routine, since that is the typical end-user desire;
* use setMaximumInteger if you want to set a real value.
* For negative numbers, use a second pattern, separated by a semicolon
* <P>Example <code>"#,#00.0#"</code> → 1,234.56
* <P>This means a minimum of 2 integer digits, 1 fraction digit, and
* a maximum of 2 fraction digits.
* <p>Example: <code>"#,#00.0#;(#,#00.0#)"</code> for negatives in
* parentheses.
* <p>In negative patterns, the minimum and maximum counts are ignored;
* these are presumed to be set in the positive pattern.
*
* @param pattern a new pattern
* @exception NullPointerException if <code>pattern</code> is null
* @exception IllegalArgumentException if the given pattern is invalid.
*/
public void applyLocalizedPattern(String pattern) {
applyPattern(pattern, true);
} /**
* Does the real work of applying a pattern.
*/
private void applyPattern(String pattern, boolean localized) {
char zeroDigit = PATTERN_ZERO_DIGIT;
char groupingSeparator = PATTERN_GROUPING_SEPARATOR;
char decimalSeparator = PATTERN_DECIMAL_SEPARATOR;
char percent = PATTERN_PERCENT;
char perMill = PATTERN_PER_MILLE;
char digit = PATTERN_DIGIT;
char separator = PATTERN_SEPARATOR;
String exponent = PATTERN_EXPONENT;
char minus = PATTERN_MINUS;
if (localized) {
zeroDigit = symbols.getZeroDigit();
groupingSeparator = symbols.getGroupingSeparator();
decimalSeparator = symbols.getDecimalSeparator();
percent = symbols.getPercent();
perMill = symbols.getPerMill();
digit = symbols.getDigit();
separator = symbols.getPatternSeparator();
exponent = symbols.getExponentSeparator();
minus = symbols.getMinusSign();
}
boolean gotNegative = false;
decimalSeparatorAlwaysShown = false;
isCurrencyFormat = false;
useExponentialNotation = false; // Two variables are used to record the subrange of the pattern
// occupied by phase 1. This is used during the processing of the
// second pattern (the one representing negative numbers) to ensure
// that no deviation exists in phase 1 between the two patterns.
int phaseOneStart = 0;
int phaseOneLength = 0; int start = 0;
for (int j = 1; j >= 0 && start < pattern.length(); --j) {
boolean inQuote = false;
StringBuffer prefix = new StringBuffer();
StringBuffer suffix = new StringBuffer();
int decimalPos = -1;
int multiplier = 1;
int digitLeftCount = 0, zeroDigitCount = 0, digitRightCount = 0;
byte groupingCount = -1; // The phase ranges from 0 to 2. Phase 0 is the prefix. Phase 1 is
// the section of the pattern with digits, decimal separator,
// grouping characters. Phase 2 is the suffix. In phases 0 and 2,
// percent, per mille, and currency symbols are recognized and
// translated. The separation of the characters into phases is
// strictly enforced; if phase 1 characters are to appear in the
// suffix, for example, they must be quoted.
int phase = 0; // The affix is either the prefix or the suffix.
StringBuffer affix = prefix; for (int pos = start; pos < pattern.length(); ++pos) {
char ch = pattern.charAt(pos);
switch (phase) {
case 0:
case 2:
// Process the prefix / suffix characters
if (inQuote) {
// A quote within quotes indicates either the closing
// quote or two quotes, which is a quote literal. That
// is, we have the second quote in 'do' or 'don''t'.
if (ch == QUOTE) {
if ((pos+1) < pattern.length() &&
pattern.charAt(pos+1) == QUOTE) {
++pos;
affix.append("''"); // 'don''t'
} else {
inQuote = false; // 'do'
}
continue;
}
} else {
// Process unquoted characters seen in prefix or suffix
// phase.
if (ch == digit ||
ch == zeroDigit ||
ch == groupingSeparator ||
ch == decimalSeparator) {
phase = 1;
if (j == 1) {
phaseOneStart = pos;
}
--pos; // Reprocess this character
continue;
} else if (ch == CURRENCY_SIGN) {
// Use lookahead to determine if the currency sign
// is doubled or not.
boolean doubled = (pos + 1) < pattern.length() &&
pattern.charAt(pos + 1) == CURRENCY_SIGN;
if (doubled) { // Skip over the doubled character
++pos;
}
isCurrencyFormat = true;
affix.append(doubled ? "'\u00A4\u00A4" : "'\u00A4");
continue;
} else if (ch == QUOTE) {
// A quote outside quotes indicates either the
// opening quote or two quotes, which is a quote
// literal. That is, we have the first quote in 'do'
// or o''clock.
if (ch == QUOTE) {
if ((pos+1) < pattern.length() &&
pattern.charAt(pos+1) == QUOTE) {
++pos;
affix.append("''"); // o''clock
} else {
inQuote = true; // 'do'
}
continue;
}
} else if (ch == separator) {
// Don't allow separators before we see digit
// characters of phase 1, and don't allow separators
// in the second pattern (j == 0).
if (phase == 0 || j == 0) {
throw new IllegalArgumentException("Unquoted special character '" +
ch + "' in pattern \"" + pattern + '"');
}
start = pos + 1;
pos = pattern.length();
continue;
} // Next handle characters which are appended directly.
else if (ch == percent) {
if (multiplier != 1) {
throw new IllegalArgumentException("Too many percent/per mille characters in pattern \"" +
pattern + '"');
}
multiplier = 100;
affix.append("'%");
continue;
} else if (ch == perMill) {
if (multiplier != 1) {
throw new IllegalArgumentException("Too many percent/per mille characters in pattern \"" +
pattern + '"');
}
multiplier = 1000;
affix.append("'\u2030");
continue;
} else if (ch == minus) {
affix.append("'-");
continue;
}
}
// Note that if we are within quotes, or if this is an
// unquoted, non-special character, then we usually fall
// through to here.
affix.append(ch);
break; case 1:
// Phase one must be identical in the two sub-patterns. We
// enforce this by doing a direct comparison. While
// processing the first sub-pattern, we just record its
// length. While processing the second, we compare
// characters.
if (j == 1) {
++phaseOneLength;
} else {
if (--phaseOneLength == 0) {
phase = 2;
affix = suffix;
}
continue;
} // Process the digits, decimal, and grouping characters. We
// record five pieces of information. We expect the digits
// to occur in the pattern ####0000.####, and we record the
// number of left digits, zero (central) digits, and right
// digits. The position of the last grouping character is
// recorded (should be somewhere within the first two blocks
// of characters), as is the position of the decimal point,
// if any (should be in the zero digits). If there is no
// decimal point, then there should be no right digits.
if (ch == digit) {
if (zeroDigitCount > 0) {
++digitRightCount;
} else {
++digitLeftCount;
}
if (groupingCount >= 0 && decimalPos < 0) {
++groupingCount;
}
} else if (ch == zeroDigit) {
if (digitRightCount > 0) {
throw new IllegalArgumentException("Unexpected '0' in pattern \"" +
pattern + '"');
}
++zeroDigitCount;
if (groupingCount >= 0 && decimalPos < 0) {
++groupingCount;
}
} else if (ch == groupingSeparator) {
groupingCount = 0;
} else if (ch == decimalSeparator) {
if (decimalPos >= 0) {
throw new IllegalArgumentException("Multiple decimal separators in pattern \"" +
pattern + '"');
}
decimalPos = digitLeftCount + zeroDigitCount + digitRightCount;
} else if (pattern.regionMatches(pos, exponent, 0, exponent.length())){
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.
pos = pos+exponent.length();
while (pos < pattern.length() &&
pattern.charAt(pos) == zeroDigit) {
++minExponentDigits;
++phaseOneLength;
++pos;
} if ((digitLeftCount + zeroDigitCount) < 1 ||
minExponentDigits < 1) {
throw new IllegalArgumentException("Malformed exponential " +
"pattern \"" + pattern + '"');
} // Transition to phase 2
phase = 2;
affix = suffix;
--pos;
continue;
} else {
phase = 2;
affix = suffix;
--pos;
--phaseOneLength;
continue;
}
break;
}
} // Handle patterns with no '0' pattern character. These patterns
// are legal, but must be interpreted. "##.###" -> "#0.###".
// ".###" -> ".0##".
/* We allow patterns of the form "####" to produce a zeroDigitCount
* of zero (got that?); although this seems like it might make it
* possible for format() to produce empty strings, format() checks
* for this condition and outputs a zero digit in this situation.
* Having a zeroDigitCount of zero yields a minimum integer digits
* of zero, which allows proper round-trip patterns. That is, we
* don't want "#" to become "#0" when toPattern() is called (even
* though that's what it really is, semantically).
*/
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 || inQuote) {
throw new IllegalArgumentException("Malformed pattern \"" +
pattern + '"');
} if (j == 1) {
posPrefixPattern = prefix.toString();
posSuffixPattern = suffix.toString();
negPrefixPattern = posPrefixPattern; // assume these for now
negSuffixPattern = posSuffixPattern;
int digitTotalCount = digitLeftCount + zeroDigitCount + digitRightCount;
/* 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 : digitTotalCount;
setMinimumIntegerDigits(effectiveDecimalPos - digitLeftCount);
setMaximumIntegerDigits(useExponentialNotation ?
digitLeftCount + getMinimumIntegerDigits() :
MAXIMUM_INTEGER_DIGITS);
setMaximumFractionDigits(decimalPos >= 0 ?
(digitTotalCount - decimalPos) : 0);
setMinimumFractionDigits(decimalPos >= 0 ?
(digitLeftCount + zeroDigitCount - decimalPos) : 0);
setGroupingUsed(groupingCount > 0);
this.groupingSize = (groupingCount > 0) ? groupingCount : 0;
this.multiplier = multiplier;
setDecimalSeparatorAlwaysShown(decimalPos == 0 ||
decimalPos == digitTotalCount);
} else {
negPrefixPattern = prefix.toString();
negSuffixPattern = suffix.toString();
gotNegative = true;
}
} if (pattern.length() == 0) {
posPrefixPattern = posSuffixPattern = "";
setMinimumIntegerDigits(0);
setMaximumIntegerDigits(MAXIMUM_INTEGER_DIGITS);
setMinimumFractionDigits(0);
setMaximumFractionDigits(MAXIMUM_FRACTION_DIGITS);
} // If there was no negative pattern, or if the negative pattern is
// identical to the positive pattern, then prepend the minus sign to
// the positive pattern to form the negative pattern.
if (!gotNegative ||
(negPrefixPattern.equals(posPrefixPattern)
&& negSuffixPattern.equals(posSuffixPattern))) {
negSuffixPattern = posSuffixPattern;
negPrefixPattern = "'-" + posPrefixPattern;
} expandAffixes();
} /**
* Sets the maximum number of digits allowed in the integer portion of a
* number.
* For formatting numbers other than <code>BigInteger</code> and
* <code>BigDecimal</code> objects, the lower of <code>newValue</code> and
* 309 is used. Negative input values are replaced with 0.
* @see NumberFormat#setMaximumIntegerDigits
*/
@Override
public void setMaximumIntegerDigits(int newValue) {
maximumIntegerDigits = Math.min(Math.max(0, newValue), MAXIMUM_INTEGER_DIGITS);
super.setMaximumIntegerDigits((maximumIntegerDigits > DOUBLE_INTEGER_DIGITS) ?
DOUBLE_INTEGER_DIGITS : maximumIntegerDigits);
if (minimumIntegerDigits > maximumIntegerDigits) {
minimumIntegerDigits = maximumIntegerDigits;
super.setMinimumIntegerDigits((minimumIntegerDigits > DOUBLE_INTEGER_DIGITS) ?
DOUBLE_INTEGER_DIGITS : minimumIntegerDigits);
}
fastPathCheckNeeded = true;
} /**
* Sets the minimum number of digits allowed in the integer portion of a
* number.
* For formatting numbers other than <code>BigInteger</code> and
* <code>BigDecimal</code> objects, the lower of <code>newValue</code> and
* 309 is used. Negative input values are replaced with 0.
* @see NumberFormat#setMinimumIntegerDigits
*/
@Override
public void setMinimumIntegerDigits(int newValue) {
minimumIntegerDigits = Math.min(Math.max(0, newValue), MAXIMUM_INTEGER_DIGITS);
super.setMinimumIntegerDigits((minimumIntegerDigits > DOUBLE_INTEGER_DIGITS) ?
DOUBLE_INTEGER_DIGITS : minimumIntegerDigits);
if (minimumIntegerDigits > maximumIntegerDigits) {
maximumIntegerDigits = minimumIntegerDigits;
super.setMaximumIntegerDigits((maximumIntegerDigits > DOUBLE_INTEGER_DIGITS) ?
DOUBLE_INTEGER_DIGITS : maximumIntegerDigits);
}
fastPathCheckNeeded = true;
} /**
* Sets the maximum number of digits allowed in the fraction portion of a
* number.
* For formatting numbers other than <code>BigInteger</code> and
* <code>BigDecimal</code> objects, the lower of <code>newValue</code> and
* 340 is used. Negative input values are replaced with 0.
* @see NumberFormat#setMaximumFractionDigits
*/
@Override
public void setMaximumFractionDigits(int newValue) {
maximumFractionDigits = Math.min(Math.max(0, newValue), MAXIMUM_FRACTION_DIGITS);
super.setMaximumFractionDigits((maximumFractionDigits > DOUBLE_FRACTION_DIGITS) ?
DOUBLE_FRACTION_DIGITS : maximumFractionDigits);
if (minimumFractionDigits > maximumFractionDigits) {
minimumFractionDigits = maximumFractionDigits;
super.setMinimumFractionDigits((minimumFractionDigits > DOUBLE_FRACTION_DIGITS) ?
DOUBLE_FRACTION_DIGITS : minimumFractionDigits);
}
fastPathCheckNeeded = true;
} /**
* Sets the minimum number of digits allowed in the fraction portion of a
* number.
* For formatting numbers other than <code>BigInteger</code> and
* <code>BigDecimal</code> objects, the lower of <code>newValue</code> and
* 340 is used. Negative input values are replaced with 0.
* @see NumberFormat#setMinimumFractionDigits
*/
@Override
public void setMinimumFractionDigits(int newValue) {
minimumFractionDigits = Math.min(Math.max(0, newValue), MAXIMUM_FRACTION_DIGITS);
super.setMinimumFractionDigits((minimumFractionDigits > DOUBLE_FRACTION_DIGITS) ?
DOUBLE_FRACTION_DIGITS : minimumFractionDigits);
if (minimumFractionDigits > maximumFractionDigits) {
maximumFractionDigits = minimumFractionDigits;
super.setMaximumFractionDigits((maximumFractionDigits > DOUBLE_FRACTION_DIGITS) ?
DOUBLE_FRACTION_DIGITS : maximumFractionDigits);
}
fastPathCheckNeeded = true;
} /**
* Gets the maximum number of digits allowed in the integer portion of a
* number.
* For formatting numbers other than <code>BigInteger</code> and
* <code>BigDecimal</code> objects, the lower of the return value and
* 309 is used.
* @see #setMaximumIntegerDigits
*/
@Override
public int getMaximumIntegerDigits() {
return maximumIntegerDigits;
} /**
* Gets the minimum number of digits allowed in the integer portion of a
* number.
* For formatting numbers other than <code>BigInteger</code> and
* <code>BigDecimal</code> objects, the lower of the return value and
* 309 is used.
* @see #setMinimumIntegerDigits
*/
@Override
public int getMinimumIntegerDigits() {
return minimumIntegerDigits;
} /**
* Gets the maximum number of digits allowed in the fraction portion of a
* number.
* For formatting numbers other than <code>BigInteger</code> and
* <code>BigDecimal</code> objects, the lower of the return value and
* 340 is used.
* @see #setMaximumFractionDigits
*/
@Override
public int getMaximumFractionDigits() {
return maximumFractionDigits;
} /**
* Gets the minimum number of digits allowed in the fraction portion of a
* number.
* For formatting numbers other than <code>BigInteger</code> and
* <code>BigDecimal</code> objects, the lower of the return value and
* 340 is used.
* @see #setMinimumFractionDigits
*/
@Override
public int getMinimumFractionDigits() {
return minimumFractionDigits;
} /**
* Gets the currency used by this decimal format when formatting
* currency values.
* The currency is obtained by calling
* {@link DecimalFormatSymbols#getCurrency DecimalFormatSymbols.getCurrency}
* on this number format's symbols.
*
* @return the currency used by this decimal format, or <code>null</code>
* @since 1.4
*/
@Override
public Currency getCurrency() {
return symbols.getCurrency();
} /**
* Sets the currency used by this number format when formatting
* currency values. This does not update the minimum or maximum
* number of fraction digits used by the number format.
* The currency is set by calling
* {@link DecimalFormatSymbols#setCurrency DecimalFormatSymbols.setCurrency}
* on this number format's symbols.
*
* @param currency the new currency to be used by this decimal format
* @exception NullPointerException if <code>currency</code> is null
* @since 1.4
*/
@Override
public void setCurrency(Currency currency) {
if (currency != symbols.getCurrency()) {
symbols.setCurrency(currency);
if (isCurrencyFormat) {
expandAffixes();
}
}
fastPathCheckNeeded = true;
} /**
* Gets the {@link java.math.RoundingMode} used in this DecimalFormat.
*
* @return The <code>RoundingMode</code> used for this DecimalFormat.
* @see #setRoundingMode(RoundingMode)
* @since 1.6
*/
@Override
public RoundingMode getRoundingMode() {
return roundingMode;
} /**
* Sets the {@link java.math.RoundingMode} used in this DecimalFormat.
*
* @param roundingMode The <code>RoundingMode</code> to be used
* @see #getRoundingMode()
* @exception NullPointerException if <code>roundingMode</code> is null.
* @since 1.6
*/
@Override
public void setRoundingMode(RoundingMode roundingMode) {
if (roundingMode == null) {
throw new NullPointerException();
} this.roundingMode = roundingMode;
digitList.setRoundingMode(roundingMode);
fastPathCheckNeeded = true;
} /**
* Reads the default serializable fields from the stream and performs
* validations and adjustments for older serialized versions. The
* validations and adjustments are:
* <ol>
* <li>
* Verify that the superclass's digit count fields correctly reflect
* the limits imposed on formatting numbers other than
* <code>BigInteger</code> and <code>BigDecimal</code> objects. These
* limits are stored in the superclass for serialization compatibility
* with older versions, while the limits for <code>BigInteger</code> and
* <code>BigDecimal</code> objects are kept in this class.
* If, in the superclass, the minimum or maximum integer digit count is
* larger than <code>DOUBLE_INTEGER_DIGITS</code> or if the minimum or
* maximum fraction digit count is larger than
* <code>DOUBLE_FRACTION_DIGITS</code>, then the stream data is invalid
* and this method throws an <code>InvalidObjectException</code>.
* <li>
* If <code>serialVersionOnStream</code> is less than 4, initialize
* <code>roundingMode</code> to {@link java.math.RoundingMode#HALF_EVEN
* RoundingMode.HALF_EVEN}. This field is new with version 4.
* <li>
* If <code>serialVersionOnStream</code> is less than 3, then call
* the setters for the minimum and maximum integer and fraction digits with
* the values of the corresponding superclass getters to initialize the
* fields in this class. The fields in this class are new with version 3.
* <li>
* If <code>serialVersionOnStream</code> is less than 1, indicating that
* the stream was written by JDK 1.1, initialize
* <code>useExponentialNotation</code>
* to false, since it was not present in JDK 1.1.
* <li>
* Set <code>serialVersionOnStream</code> to the maximum allowed value so
* that default serialization will work properly if this object is streamed
* out again.
* </ol>
*
* <p>Stream versions older than 2 will not have the affix pattern variables
* <code>posPrefixPattern</code> etc. As a result, they will be initialized
* to <code>null</code>, which means the affix strings will be taken as
* literal values. This is exactly what we want, since that corresponds to
* the pre-version-2 behavior.
*/
private void readObject(ObjectInputStream stream)
throws IOException, ClassNotFoundException
{
stream.defaultReadObject();
digitList = new DigitList(); // We force complete fast-path reinitialization when the instance is
// deserialized. See clone() comment on fastPathCheckNeeded.
fastPathCheckNeeded = true;
isFastPath = false;
fastPathData = null; if (serialVersionOnStream < 4) {
setRoundingMode(RoundingMode.HALF_EVEN);
} else {
setRoundingMode(getRoundingMode());
} // We only need to check the maximum counts because NumberFormat
// .readObject has already ensured that the maximum is greater than the
// minimum count.
if (super.getMaximumIntegerDigits() > DOUBLE_INTEGER_DIGITS ||
super.getMaximumFractionDigits() > DOUBLE_FRACTION_DIGITS) {
throw new InvalidObjectException("Digit count out of range");
}
if (serialVersionOnStream < 3) {
setMaximumIntegerDigits(super.getMaximumIntegerDigits());
setMinimumIntegerDigits(super.getMinimumIntegerDigits());
setMaximumFractionDigits(super.getMaximumFractionDigits());
setMinimumFractionDigits(super.getMinimumFractionDigits());
}
if (serialVersionOnStream < 1) {
// Didn't have exponential fields
useExponentialNotation = false;
}
serialVersionOnStream = currentSerialVersion;
} //----------------------------------------------------------------------
// INSTANCE VARIABLES
//---------------------------------------------------------------------- private transient DigitList digitList = new DigitList(); /**
* The symbol used as a prefix when formatting positive numbers, e.g. "+".
*
* @serial
* @see #getPositivePrefix
*/
private String positivePrefix = ""; /**
* The symbol used as a suffix when formatting positive numbers.
* This is often an empty string.
*
* @serial
* @see #getPositiveSuffix
*/
private String positiveSuffix = ""; /**
* The symbol used as a prefix when formatting negative numbers, e.g. "-".
*
* @serial
* @see #getNegativePrefix
*/
private String negativePrefix = "-"; /**
* The symbol used as a suffix when formatting negative numbers.
* This is often an empty string.
*
* @serial
* @see #getNegativeSuffix
*/
private String negativeSuffix = ""; /**
* The prefix pattern for non-negative numbers. This variable corresponds
* to <code>positivePrefix</code>.
*
* <p>This pattern is expanded by the method <code>expandAffix()</code> to
* <code>positivePrefix</code> to update the latter to reflect changes in
* <code>symbols</code>. If this variable is <code>null</code> then
* <code>positivePrefix</code> is taken as a literal value that does not
* change when <code>symbols</code> changes. This variable is always
* <code>null</code> for <code>DecimalFormat</code> objects older than
* stream version 2 restored from stream.
*
* @serial
* @since 1.3
*/
private String posPrefixPattern; /**
* The suffix pattern for non-negative numbers. This variable corresponds
* to <code>positiveSuffix</code>. This variable is analogous to
* <code>posPrefixPattern</code>; see that variable for further
* documentation.
*
* @serial
* @since 1.3
*/
private String posSuffixPattern; /**
* The prefix pattern for negative numbers. This variable corresponds
* to <code>negativePrefix</code>. This variable is analogous to
* <code>posPrefixPattern</code>; see that variable for further
* documentation.
*
* @serial
* @since 1.3
*/
private String negPrefixPattern; /**
* The suffix pattern for negative numbers. This variable corresponds
* to <code>negativeSuffix</code>. This variable is analogous to
* <code>posPrefixPattern</code>; see that variable for further
* documentation.
*
* @serial
* @since 1.3
*/
private String negSuffixPattern; /**
* The multiplier for use in percent, per mille, etc.
*
* @serial
* @see #getMultiplier
*/
private int multiplier = 1; /**
* The number of digits between grouping separators in the integer
* portion of a number. Must be greater than 0 if
* <code>NumberFormat.groupingUsed</code> is true.
*
* @serial
* @see #getGroupingSize
* @see java.text.NumberFormat#isGroupingUsed
*/
private byte groupingSize = 3; // invariant, > 0 if useThousands /**
* If true, forces the decimal separator to always appear in a formatted
* number, even if the fractional part of the number is zero.
*
* @serial
* @see #isDecimalSeparatorAlwaysShown
*/
private boolean decimalSeparatorAlwaysShown = false; /**
* If true, parse returns BigDecimal wherever possible.
*
* @serial
* @see #isParseBigDecimal
* @since 1.5
*/
private boolean parseBigDecimal = false; /**
* True if this object represents a currency format. This determines
* whether the monetary decimal separator is used instead of the normal one.
*/
private transient boolean isCurrencyFormat = false; /**
* The <code>DecimalFormatSymbols</code> object used by this format.
* It contains the symbols used to format numbers, e.g. the grouping separator,
* decimal separator, and so on.
*
* @serial
* @see #setDecimalFormatSymbols
* @see java.text.DecimalFormatSymbols
*/
private DecimalFormatSymbols symbols = null; // LIU new DecimalFormatSymbols(); /**
* True to force the use of exponential (i.e. scientific) notation when formatting
* numbers.
*
* @serial
* @since 1.2
*/
private boolean useExponentialNotation; // Newly persistent in the Java 2 platform v.1.2 /**
* FieldPositions describing the positive prefix String. This is
* lazily created. Use <code>getPositivePrefixFieldPositions</code>
* when needed.
*/
private transient FieldPosition[] positivePrefixFieldPositions; /**
* FieldPositions describing the positive suffix String. This is
* lazily created. Use <code>getPositiveSuffixFieldPositions</code>
* when needed.
*/
private transient FieldPosition[] positiveSuffixFieldPositions; /**
* FieldPositions describing the negative prefix String. This is
* lazily created. Use <code>getNegativePrefixFieldPositions</code>
* when needed.
*/
private transient FieldPosition[] negativePrefixFieldPositions; /**
* FieldPositions describing the negative suffix String. This is
* lazily created. Use <code>getNegativeSuffixFieldPositions</code>
* when needed.
*/
private transient FieldPosition[] negativeSuffixFieldPositions; /**
* The minimum number of digits used to display the exponent when a number is
* formatted in exponential notation. This field is ignored if
* <code>useExponentialNotation</code> is not true.
*
* @serial
* @since 1.2
*/
private byte minExponentDigits; // Newly persistent in the Java 2 platform v.1.2 /**
* The maximum number of digits allowed in the integer portion of a
* <code>BigInteger</code> or <code>BigDecimal</code> number.
* <code>maximumIntegerDigits</code> must be greater than or equal to
* <code>minimumIntegerDigits</code>.
*
* @serial
* @see #getMaximumIntegerDigits
* @since 1.5
*/
private int maximumIntegerDigits = super.getMaximumIntegerDigits(); /**
* The minimum number of digits allowed in the integer portion of a
* <code>BigInteger</code> or <code>BigDecimal</code> number.
* <code>minimumIntegerDigits</code> must be less than or equal to
* <code>maximumIntegerDigits</code>.
*
* @serial
* @see #getMinimumIntegerDigits
* @since 1.5
*/
private int minimumIntegerDigits = super.getMinimumIntegerDigits(); /**
* The maximum number of digits allowed in the fractional portion of a
* <code>BigInteger</code> or <code>BigDecimal</code> number.
* <code>maximumFractionDigits</code> must be greater than or equal to
* <code>minimumFractionDigits</code>.
*
* @serial
* @see #getMaximumFractionDigits
* @since 1.5
*/
private int maximumFractionDigits = super.getMaximumFractionDigits(); /**
* The minimum number of digits allowed in the fractional portion of a
* <code>BigInteger</code> or <code>BigDecimal</code> number.
* <code>minimumFractionDigits</code> must be less than or equal to
* <code>maximumFractionDigits</code>.
*
* @serial
* @see #getMinimumFractionDigits
* @since 1.5
*/
private int minimumFractionDigits = super.getMinimumFractionDigits(); /**
* The {@link java.math.RoundingMode} used in this DecimalFormat.
*
* @serial
* @since 1.6
*/
private RoundingMode roundingMode = RoundingMode.HALF_EVEN; // ------ DecimalFormat fields for fast-path for double algorithm ------ /**
* Helper inner utility class for storing the data used in the fast-path
* algorithm. Almost all fields related to fast-path are encapsulated in
* this class.
*
* Any {@code DecimalFormat} instance has a {@code fastPathData}
* reference field that is null unless both the properties of the instance
* are such that the instance is in the "fast-path" state, and a format call
* has been done at least once while in this state.
*
* Almost all fields are related to the "fast-path" state only and don't
* change until one of the instance properties is changed.
*
* {@code firstUsedIndex} and {@code lastFreeIndex} are the only
* two fields that are used and modified while inside a call to
* {@code fastDoubleFormat}.
*
*/
private static class FastPathData {
// --- Temporary fields used in fast-path, shared by several methods. /** The first unused index at the end of the formatted result. */
int lastFreeIndex; /** The first used index at the beginning of the formatted result */
int firstUsedIndex; // --- State fields related to fast-path status. Changes due to a
// property change only. Set by checkAndSetFastPathStatus() only. /** Difference between locale zero and default zero representation. */
int zeroDelta; /** Locale char for grouping separator. */
char groupingChar; /** Fixed index position of last integral digit of formatted result */
int integralLastIndex; /** Fixed index position of first fractional digit of formatted result */
int fractionalFirstIndex; /** Fractional constants depending on decimal|currency state */
double fractionalScaleFactor;
int fractionalMaxIntBound; /** The char array buffer that will contain the formatted result */
char[] fastPathContainer; /** Suffixes recorded as char array for efficiency. */
char[] charsPositivePrefix;
char[] charsNegativePrefix;
char[] charsPositiveSuffix;
char[] charsNegativeSuffix;
boolean positiveAffixesRequired = true;
boolean negativeAffixesRequired = true;
} /** The format fast-path status of the instance. Logical state. */
private transient boolean isFastPath = false; /** Flag stating need of check and reinit fast-path status on next format call. */
private transient boolean fastPathCheckNeeded = true; /** DecimalFormat reference to its FastPathData */
private transient FastPathData fastPathData; //---------------------------------------------------------------------- static final int currentSerialVersion = 4; /**
* The internal serial version which says which version was written.
* Possible values are:
* <ul>
* <li><b>0</b> (default): versions before the Java 2 platform v1.2
* <li><b>1</b>: version for 1.2, which includes the two new fields
* <code>useExponentialNotation</code> and
* <code>minExponentDigits</code>.
* <li><b>2</b>: version for 1.3 and later, which adds four new fields:
* <code>posPrefixPattern</code>, <code>posSuffixPattern</code>,
* <code>negPrefixPattern</code>, and <code>negSuffixPattern</code>.
* <li><b>3</b>: version for 1.5 and later, which adds five new fields:
* <code>maximumIntegerDigits</code>,
* <code>minimumIntegerDigits</code>,
* <code>maximumFractionDigits</code>,
* <code>minimumFractionDigits</code>, and
* <code>parseBigDecimal</code>.
* <li><b>4</b>: version for 1.6 and later, which adds one new field:
* <code>roundingMode</code>.
* </ul>
* @since 1.2
* @serial
*/
private int serialVersionOnStream = currentSerialVersion; //----------------------------------------------------------------------
// CONSTANTS
//---------------------------------------------------------------------- // ------ Fast-Path for double Constants ------ /** Maximum valid integer value for applying fast-path algorithm */
private static final double MAX_INT_AS_DOUBLE = (double) Integer.MAX_VALUE; /**
* The digit arrays used in the fast-path methods for collecting digits.
* Using 3 constants arrays of chars ensures a very fast collection of digits
*/
private static class DigitArrays {
static final char[] DigitOnes1000 = new char[1000];
static final char[] DigitTens1000 = new char[1000];
static final char[] DigitHundreds1000 = new char[1000]; // initialize on demand holder class idiom for arrays of digits
static {
int tenIndex = 0;
int hundredIndex = 0;
char digitOne = '0';
char digitTen = '0';
char digitHundred = '0';
for (int i = 0; i < 1000; i++ ) { DigitOnes1000[i] = digitOne;
if (digitOne == '9')
digitOne = '0';
else
digitOne++; DigitTens1000[i] = digitTen;
if (i == (tenIndex + 9)) {
tenIndex += 10;
if (digitTen == '9')
digitTen = '0';
else
digitTen++;
} DigitHundreds1000[i] = digitHundred;
if (i == (hundredIndex + 99)) {
digitHundred++;
hundredIndex += 100;
}
}
}
}
// ------ Fast-Path for double Constants end ------ // Constants for characters used in programmatic (unlocalized) patterns.
private static final char PATTERN_ZERO_DIGIT = '0';
private static final char PATTERN_GROUPING_SEPARATOR = ',';
private static final char PATTERN_DECIMAL_SEPARATOR = '.';
private static final char PATTERN_PER_MILLE = '\u2030';
private static final char PATTERN_PERCENT = '%';
private static final char PATTERN_DIGIT = '#';
private static final char PATTERN_SEPARATOR = ';';
private static final String PATTERN_EXPONENT = "E";
private static final char PATTERN_MINUS = '-'; /**
* The CURRENCY_SIGN is the standard Unicode symbol for currency. It
* is used in patterns and substituted with either the currency symbol,
* or if it is doubled, with the international currency symbol. If the
* CURRENCY_SIGN is seen in a pattern, then the decimal separator is
* replaced with the monetary decimal separator.
*
* The CURRENCY_SIGN is not localized.
*/
private static final char CURRENCY_SIGN = '\u00A4'; private static final char QUOTE = '\''; private static FieldPosition[] EmptyFieldPositionArray = new FieldPosition[0]; // Upper limit on integer and fraction digits for a Java double
static final int DOUBLE_INTEGER_DIGITS = 309;
static final int DOUBLE_FRACTION_DIGITS = 340; // Upper limit on integer and fraction digits for BigDecimal and BigInteger
static final int MAXIMUM_INTEGER_DIGITS = Integer.MAX_VALUE;
static final int MAXIMUM_FRACTION_DIGITS = Integer.MAX_VALUE; // Proclaim JDK 1.1 serial compatibility.
static final long serialVersionUID = 864413376551465018L;
}