/*
 * @(#)DecimalFormat.java	1.79 04/06/28
 *
 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
 * SUN 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.InvalidObjectException;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Currency;
import java.util.Hashtable;
import java.util.Locale;
import java.util.ResourceBundle;
import sun.text.resources.LocaleData;

/**
 * <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.
 *
 * <h4>Patterns</h4>
 *
 * <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 border=0 cellspacing=3 cellpadding=0 summary="Chart showing symbol,
 *  location, localized, and meaning.">
 *     <tr bgcolor="#ccccff">
 *          <th align=left>Symbol
 *          <th align=left>Location
 *          <th align=left>Localized?
 *          <th align=left>Meaning
 *     <tr valign=top>
 *          <td><code>0</code>
 *          <td>Number
 *          <td>Yes
 *          <td>Digit
 *     <tr valign=top bgcolor="#eeeeff">
 *          <td><code>#</code>
 *          <td>Number
 *          <td>Yes
 *          <td>Digit, zero shows as absent
 *     <tr valign=top>
 *          <td><code>.</code>
 *          <td>Number
 *          <td>Yes
 *          <td>Decimal separator or monetary decimal separator
 *     <tr valign=top bgcolor="#eeeeff">
 *          <td><code>-</code>
 *          <td>Number
 *          <td>Yes
 *          <td>Minus sign
 *     <tr valign=top>
 *          <td><code>,</code>
 *          <td>Number
 *          <td>Yes
 *          <td>Grouping separator
 *     <tr valign=top bgcolor="#eeeeff">
 *          <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 valign=top>
 *          <td><code></code>
 *          <td>Subpattern boundary
 *          <td>Yes
 *          <td>Separates positive and negative subpatterns
 *     <tr valign=top bgcolor="#eeeeff">
 *          <td><code>%</code>
 *          <td>Prefix or suffix
 *          <td>Yes
 *          <td>Multiply by 100 and show as percentage
 *     <tr valign=top>
 *          <td><code>\u2030</code>
 *          <td>Prefix or suffix
 *          <td>Yes
 *          <td>Multiply by 1000 and show as per mille value
 *     <tr valign=top bgcolor="#eeeeff">
 *          <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 valign=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>.
 * </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 < 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> uses half-even rounding (see
 * {@link java.math.BigDecimal#ROUND_HALF_EVEN ROUND_HALF_EVEN}) for
 * formatting.
 *
 * <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 single character, typically
 * <code>\uFFFD</code>.  This character 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 single character, typically
 * <code>\u221E</code>, with the positive or negative prefixes and suffixes
 * applied.  The infinity character 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 name="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>
 * <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://java.sun.com/docs/books/tutorial/i18n/format/decimalFormat.html">Java Tutorial</a>
 * @see          NumberFormat
 * @see          DecimalFormatSymbols
 * @see          ParsePosition
 * @version      1.79 06/28/04
 * @author       Mark Davis
 * @author       Alan Liu
 */
public class DecimalFormat extends NumberFormat {

    /**
     * Creates a DecimalFormat using the default pattern and symbols
     * for the default 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() {
        Locale def = Locale.getDefault();
        // try to get the pattern from the cache
        String pattern = (String) cachedLocaleData.get(def);
        if (pattern == null) {  /* cache miss */
            // Get the pattern for the default locale.
            ResourceBundle rb = LocaleData.getLocaleElements(def);
            String[] all = rb.getStringArray("NumberPatterns");
            pattern = all[0];
            /* update cache */
            cachedLocaleData.put(def, pattern);
        }

        // Always applyPattern after the symbols are set
        this.symbols = new DecimalFormatSymbols(def);
        applyPattern(pattern, false);
    }


    /**
     * Creates a DecimalFormat using the given pattern and the symbols
     * for the default 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 = new DecimalFormatSymbols(Locale.getDefault());
        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
     * @see              java.text.FieldPosition
     */
    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 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.
     * @return The formatted number string
     * @see java.text.FieldPosition
     */
    public StringBuffer format(double number, StringBuffer result,
                               FieldPosition fieldPosition) {
        fieldPosition.setBeginIndex(0);
        fieldPosition.setEndIndex(0);

        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
     * @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(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.
     * @return The formatted number string
     * @see java.text.FieldPosition
     */
    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
     * @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(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
     * @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
     * @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(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
     * @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
     * @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(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.
     * @param obj The object to format
     * @return AttributedCharacterIterator describing the formatted value.
     * @since 1.4
     */
    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) {
            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());
    }

    /**
     * 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.getExponentialSymbol());

            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(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.
     */
    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 new Double(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 new Double(Double.POSITIVE_INFINITY);
            } else {
                return new Double(Double.NEGATIVE_INFINITY);
            }
        }

        if (multiplier == 0) {
            if (digitList.isZero()) {
                return new Double(Double.NaN);
            } else if (status[STATUS_POSITIVE]) {
                return new Double(Double.POSITIVE_INFINITY);
            } else {
                return new Double(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(), BigDecimal.ROUND_HALF_EVEN);
                }
            }

            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();
            }

            return gotDouble ?
                (Number)new Double(doubleResult) : (Number)new Long(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();
            char exponentChar = symbols.getExponentialSymbol();
            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