jdk/src/share/classes/java/text/NumberFormat.java
changeset 2 90ce3da70b43
child 5506 202f599c92aa
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/text/NumberFormat.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,1162 @@
+/*
+ * Copyright 1996-2005 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * (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.io.ObjectOutputStream;
+import java.math.BigInteger;
+import java.math.RoundingMode;
+import java.text.spi.NumberFormatProvider;
+import java.util.Currency;
+import java.util.HashMap;
+import java.util.Hashtable;
+import java.util.Locale;
+import java.util.Map;
+import java.util.ResourceBundle;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.spi.LocaleServiceProvider;
+import sun.util.LocaleServiceProviderPool;
+import sun.util.resources.LocaleData;
+
+/**
+ * <code>NumberFormat</code> is the abstract base class for all number
+ * formats. This class provides the interface for formatting and parsing
+ * numbers. <code>NumberFormat</code> also provides methods for determining
+ * which locales have number formats, and what their names are.
+ *
+ * <p>
+ * <code>NumberFormat</code> helps you to format and parse numbers for any locale.
+ * Your code can be completely independent of the locale conventions for
+ * decimal points, thousands-separators, or even the particular decimal
+ * digits used, or whether the number format is even decimal.
+ *
+ * <p>
+ * To format a number for the current Locale, use one of the factory
+ * class methods:
+ * <blockquote>
+ * <pre>
+ *  myString = NumberFormat.getInstance().format(myNumber);
+ * </pre>
+ * </blockquote>
+ * If you are formatting multiple numbers, it is
+ * more efficient to get the format and use it multiple times so that
+ * the system doesn't have to fetch the information about the local
+ * language and country conventions multiple times.
+ * <blockquote>
+ * <pre>
+ * NumberFormat nf = NumberFormat.getInstance();
+ * for (int i = 0; i < myNumber.length; ++i) {
+ *     output.println(nf.format(myNumber[i]) + "; ");
+ * }
+ * </pre>
+ * </blockquote>
+ * To format a number for a different Locale, specify it in the
+ * call to <code>getInstance</code>.
+ * <blockquote>
+ * <pre>
+ * NumberFormat nf = NumberFormat.getInstance(Locale.FRENCH);
+ * </pre>
+ * </blockquote>
+ * You can also use a <code>NumberFormat</code> to parse numbers:
+ * <blockquote>
+ * <pre>
+ * myNumber = nf.parse(myString);
+ * </pre>
+ * </blockquote>
+ * Use <code>getInstance</code> or <code>getNumberInstance</code> to get the
+ * normal number format. Use <code>getIntegerInstance</code> to get an
+ * integer number format. Use <code>getCurrencyInstance</code> to get the
+ * currency number format. And use <code>getPercentInstance</code> to get a
+ * format for displaying percentages. With this format, a fraction like
+ * 0.53 is displayed as 53%.
+ *
+ * <p>
+ * You can also control the display of numbers with such methods as
+ * <code>setMinimumFractionDigits</code>.
+ * If you want even more control over the format or parsing,
+ * or want to give your users more control,
+ * you can try casting the <code>NumberFormat</code> you get from the factory methods
+ * to a <code>DecimalFormat</code>. This will work for the vast majority
+ * of locales; just remember to put it in a <code>try</code> block in case you
+ * encounter an unusual one.
+ *
+ * <p>
+ * NumberFormat and DecimalFormat are designed such that some controls
+ * work for formatting and others work for parsing.  The following is
+ * the detailed description for each these control methods,
+ * <p>
+ * setParseIntegerOnly : only affects parsing, e.g.
+ * if true,  "3456.78" -> 3456 (and leaves the parse position just after index 6)
+ * if false, "3456.78" -> 3456.78 (and leaves the parse position just after index 8)
+ * This is independent of formatting.  If you want to not show a decimal point
+ * where there might be no digits after the decimal point, use
+ * setDecimalSeparatorAlwaysShown.
+ * <p>
+ * setDecimalSeparatorAlwaysShown : only affects formatting, and only where
+ * there might be no digits after the decimal point, such as with a pattern
+ * like "#,##0.##", e.g.,
+ * if true,  3456.00 -> "3,456."
+ * if false, 3456.00 -> "3456"
+ * This is independent of parsing.  If you want parsing to stop at the decimal
+ * point, use setParseIntegerOnly.
+ *
+ * <p>
+ * You can also use forms of the <code>parse</code> and <code>format</code>
+ * methods with <code>ParsePosition</code> and <code>FieldPosition</code> to
+ * allow you to:
+ * <ul>
+ * <li> progressively parse through pieces of a string
+ * <li> align the decimal point and other areas
+ * </ul>
+ * For example, you can align numbers in two ways:
+ * <ol>
+ * <li> If you are using a monospaced font with spacing for alignment,
+ *      you can pass the <code>FieldPosition</code> in your format call, with
+ *      <code>field</code> = <code>INTEGER_FIELD</code>. On output,
+ *      <code>getEndIndex</code> will be set to the offset between the
+ *      last character of the integer and the decimal. Add
+ *      (desiredSpaceCount - getEndIndex) spaces at the front of the string.
+ *
+ * <li> If you are using proportional fonts,
+ *      instead of padding with spaces, measure the width
+ *      of the string in pixels from the start to <code>getEndIndex</code>.
+ *      Then move the pen by
+ *      (desiredPixelWidth - widthToAlignmentPoint) before drawing the text.
+ *      It also works where there is no decimal, but possibly additional
+ *      characters at the end, e.g., with parentheses in negative
+ *      numbers: "(12)" for -12.
+ * </ol>
+ *
+ * <h4><a name="synchronization">Synchronization</a></h4>
+ *
+ * <p>
+ * Number 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.
+ *
+ * @see          DecimalFormat
+ * @see          ChoiceFormat
+ * @author       Mark Davis
+ * @author       Helena Shih
+ */
+public abstract class NumberFormat extends Format  {
+
+    /**
+     * Field constant used to construct a FieldPosition object. Signifies that
+     * the position of the integer part of a formatted number should be returned.
+     * @see java.text.FieldPosition
+     */
+    public static final int INTEGER_FIELD = 0;
+
+    /**
+     * Field constant used to construct a FieldPosition object. Signifies that
+     * the position of the fraction part of a formatted number should be returned.
+     * @see java.text.FieldPosition
+     */
+    public static final int FRACTION_FIELD = 1;
+
+    /**
+     * Sole constructor.  (For invocation by subclass constructors, typically
+     * implicit.)
+     */
+    protected NumberFormat() {
+    }
+
+    /**
+     * 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 extracts the number's value using
+     * {@link java.lang.Number#longValue()} for all integral type values that
+     * can be converted to <code>long</code> without loss of information,
+     * including <code>BigInteger</code> values with a
+     * {@link java.math.BigInteger#bitLength() bit length} of less than 64,
+     * and {@link java.lang.Number#doubleValue()} for all other types. It
+     * then calls
+     * {@link #format(long,java.lang.StringBuffer,java.text.FieldPosition)}
+     * or {@link #format(double,java.lang.StringBuffer,java.text.FieldPosition)}.
+     * This may result in loss of magnitude information and precision for
+     * <code>BigInteger</code> and <code>BigDecimal</code> values.
+     * @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
+     */
+    public 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 Number) {
+            return format(((Number)number).doubleValue(), toAppendTo, pos);
+        } else {
+            throw new IllegalArgumentException("Cannot format given Object as a Number");
+        }
+    }
+
+    /**
+     * 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>
+     * See the {@link #parse(String, ParsePosition)} method for more information
+     * on number parsing.
+     *
+     * @param source A <code>String</code>, part of which should be parsed.
+     * @param pos A <code>ParsePosition</code> object with index and error
+     *            index information as described above.
+     * @return A <code>Number</code> parsed from the string. In case of
+     *         error, returns null.
+     * @exception NullPointerException if <code>pos</code> is null.
+     */
+    public final Object parseObject(String source, ParsePosition pos) {
+        return parse(source, pos);
+    }
+
+   /**
+     * Specialization of format.
+     * @exception        ArithmeticException if rounding is needed with rounding
+     *                   mode being set to RoundingMode.UNNECESSARY
+     * @see java.text.Format#format
+     */
+    public final String format(double number) {
+        return format(number, new StringBuffer(),
+                      DontCareFieldPosition.INSTANCE).toString();
+    }
+
+   /**
+     * Specialization of format.
+     * @exception        ArithmeticException if rounding is needed with rounding
+     *                   mode being set to RoundingMode.UNNECESSARY
+     * @see java.text.Format#format
+     */
+    public final String format(long number) {
+        return format(number, new StringBuffer(),
+                      DontCareFieldPosition.INSTANCE).toString();
+    }
+
+   /**
+     * Specialization of format.
+     * @exception        ArithmeticException if rounding is needed with rounding
+     *                   mode being set to RoundingMode.UNNECESSARY
+     * @see java.text.Format#format
+     */
+    public abstract StringBuffer format(double number,
+                                        StringBuffer toAppendTo,
+                                        FieldPosition pos);
+
+   /**
+     * Specialization of format.
+     * @exception        ArithmeticException if rounding is needed with rounding
+     *                   mode being set to RoundingMode.UNNECESSARY
+     * @see java.text.Format#format
+     */
+    public abstract StringBuffer format(long number,
+                                        StringBuffer toAppendTo,
+                                        FieldPosition pos);
+
+   /**
+     * Returns a Long if possible (e.g., within the range [Long.MIN_VALUE,
+     * Long.MAX_VALUE] and with no decimals), otherwise a Double.
+     * If IntegerOnly is set, will stop at a decimal
+     * point (or equivalent; e.g., for rational numbers "1 2/3", will stop
+     * after the 1).
+     * Does not throw an exception; if no object can be parsed, index is
+     * unchanged!
+     * @see java.text.NumberFormat#isParseIntegerOnly
+     * @see java.text.Format#parseObject
+     */
+    public abstract Number parse(String source, ParsePosition parsePosition);
+
+    /**
+     * Parses text from the beginning of the given string to produce a number.
+     * The method may not use the entire text of the given string.
+     * <p>
+     * See the {@link #parse(String, ParsePosition)} method for more information
+     * on number parsing.
+     *
+     * @param source A <code>String</code> whose beginning should be parsed.
+     * @return A <code>Number</code> parsed from the string.
+     * @exception ParseException if the beginning of the specified string
+     *            cannot be parsed.
+     */
+    public Number parse(String source) throws ParseException {
+        ParsePosition parsePosition = new ParsePosition(0);
+        Number result = parse(source, parsePosition);
+        if (parsePosition.index == 0) {
+            throw new ParseException("Unparseable number: \"" + source + "\"",
+                                     parsePosition.errorIndex);
+        }
+        return result;
+    }
+
+    /**
+     * Returns true if this format will parse numbers as integers only.
+     * For example in the English locale, with ParseIntegerOnly true, the
+     * string "1234." would be parsed as the integer value 1234 and parsing
+     * would stop at the "." character.  Of course, the exact format accepted
+     * by the parse operation is locale dependant and determined by sub-classes
+     * of NumberFormat.
+     */
+    public boolean isParseIntegerOnly() {
+        return parseIntegerOnly;
+    }
+
+    /**
+     * Sets whether or not numbers should be parsed as integers only.
+     * @see #isParseIntegerOnly
+     */
+    public void setParseIntegerOnly(boolean value) {
+        parseIntegerOnly = value;
+    }
+
+    //============== Locale Stuff =====================
+
+    /**
+     * Returns a general-purpose number format for the current default locale.
+     * This is the same as calling
+     * {@link #getNumberInstance() getNumberInstance()}.
+     */
+    public final static NumberFormat getInstance() {
+        return getInstance(Locale.getDefault(), NUMBERSTYLE);
+    }
+
+    /**
+     * Returns a general-purpose number format for the specified locale.
+     * This is the same as calling
+     * {@link #getNumberInstance(java.util.Locale) getNumberInstance(inLocale)}.
+     */
+    public static NumberFormat getInstance(Locale inLocale) {
+        return getInstance(inLocale, NUMBERSTYLE);
+    }
+
+    /**
+     * Returns a general-purpose number format for the current default locale.
+     */
+    public final static NumberFormat getNumberInstance() {
+        return getInstance(Locale.getDefault(), NUMBERSTYLE);
+    }
+
+    /**
+     * Returns a general-purpose number format for the specified locale.
+     */
+    public static NumberFormat getNumberInstance(Locale inLocale) {
+        return getInstance(inLocale, NUMBERSTYLE);
+    }
+
+    /**
+     * Returns an integer number format for the current default locale. The
+     * returned number format is configured to round floating point numbers
+     * to the nearest integer using half-even rounding (see {@link
+     * java.math.RoundingMode#HALF_EVEN RoundingMode.HALF_EVEN}) for formatting,
+     * and to parse only the integer part of an input string (see {@link
+     * #isParseIntegerOnly isParseIntegerOnly}).
+     *
+     * @see #getRoundingMode()
+     * @return a number format for integer values
+     * @since 1.4
+     */
+    public final static NumberFormat getIntegerInstance() {
+        return getInstance(Locale.getDefault(), INTEGERSTYLE);
+    }
+
+    /**
+     * Returns an integer number format for the specified locale. The
+     * returned number format is configured to round floating point numbers
+     * to the nearest integer using half-even rounding (see {@link
+     * java.math.RoundingMode#HALF_EVEN RoundingMode.HALF_EVEN}) for formatting,
+     * and to parse only the integer part of an input string (see {@link
+     * #isParseIntegerOnly isParseIntegerOnly}).
+     *
+     * @see #getRoundingMode()
+     * @return a number format for integer values
+     * @since 1.4
+     */
+    public static NumberFormat getIntegerInstance(Locale inLocale) {
+        return getInstance(inLocale, INTEGERSTYLE);
+    }
+
+    /**
+     * Returns a currency format for the current default locale.
+     */
+    public final static NumberFormat getCurrencyInstance() {
+        return getInstance(Locale.getDefault(), CURRENCYSTYLE);
+    }
+
+    /**
+     * Returns a currency format for the specified locale.
+     */
+    public static NumberFormat getCurrencyInstance(Locale inLocale) {
+        return getInstance(inLocale, CURRENCYSTYLE);
+    }
+
+    /**
+     * Returns a percentage format for the current default locale.
+     */
+    public final static NumberFormat getPercentInstance() {
+        return getInstance(Locale.getDefault(), PERCENTSTYLE);
+    }
+
+    /**
+     * Returns a percentage format for the specified locale.
+     */
+    public static NumberFormat getPercentInstance(Locale inLocale) {
+        return getInstance(inLocale, PERCENTSTYLE);
+    }
+
+    /**
+     * Returns a scientific format for the current default locale.
+     */
+    /*public*/ final static NumberFormat getScientificInstance() {
+        return getInstance(Locale.getDefault(), SCIENTIFICSTYLE);
+    }
+
+    /**
+     * Returns a scientific format for the specified locale.
+     */
+    /*public*/ static NumberFormat getScientificInstance(Locale inLocale) {
+        return getInstance(inLocale, SCIENTIFICSTYLE);
+    }
+
+    /**
+     * Returns an array of all locales for which the
+     * <code>get*Instance</code> methods of this class can return
+     * localized instances.
+     * The returned array represents the union of locales supported by the Java
+     * runtime and by installed
+     * {@link java.text.spi.NumberFormatProvider NumberFormatProvider} implementations.
+     * It must contain at least a <code>Locale</code> instance equal to
+     * {@link java.util.Locale#US Locale.US}.
+     *
+     * @return An array of locales for which localized
+     *         <code>NumberFormat</code> instances are available.
+     */
+    public static Locale[] getAvailableLocales() {
+        LocaleServiceProviderPool pool =
+            LocaleServiceProviderPool.getPool(NumberFormatProvider.class);
+        return pool.getAvailableLocales();
+    }
+
+    /**
+     * Overrides hashCode
+     */
+    public int hashCode() {
+        return maximumIntegerDigits * 37 + maxFractionDigits;
+        // just enough fields for a reasonable distribution
+    }
+
+    /**
+     * Overrides equals
+     */
+    public boolean equals(Object obj) {
+        if (obj == null) {
+            return false;
+        }
+        if (this == obj) {
+            return true;
+        }
+        if (getClass() != obj.getClass()) {
+            return false;
+        }
+        NumberFormat other = (NumberFormat) obj;
+        return (maximumIntegerDigits == other.maximumIntegerDigits
+            && minimumIntegerDigits == other.minimumIntegerDigits
+            && maximumFractionDigits == other.maximumFractionDigits
+            && minimumFractionDigits == other.minimumFractionDigits
+            && groupingUsed == other.groupingUsed
+            && parseIntegerOnly == other.parseIntegerOnly);
+    }
+
+    /**
+     * Overrides Cloneable
+     */
+    public Object clone() {
+        NumberFormat other = (NumberFormat) super.clone();
+        return other;
+    }
+
+    /**
+     * Returns true if grouping is used in this format. For example, in the
+     * English locale, with grouping on, the number 1234567 might be formatted
+     * as "1,234,567". The grouping separator as well as the size of each group
+     * is locale dependant and is determined by sub-classes of NumberFormat.
+     * @see #setGroupingUsed
+     */
+    public boolean isGroupingUsed() {
+        return groupingUsed;
+    }
+
+    /**
+     * Set whether or not grouping will be used in this format.
+     * @see #isGroupingUsed
+     */
+    public void setGroupingUsed(boolean newValue) {
+        groupingUsed = newValue;
+    }
+
+    /**
+     * Returns the maximum number of digits allowed in the integer portion of a
+     * number.
+     * @see #setMaximumIntegerDigits
+     */
+    public int getMaximumIntegerDigits() {
+        return maximumIntegerDigits;
+    }
+
+    /**
+     * Sets the maximum number of digits allowed in the integer portion of a
+     * number. maximumIntegerDigits must be >= minimumIntegerDigits.  If the
+     * new value for maximumIntegerDigits is less than the current value
+     * of minimumIntegerDigits, then minimumIntegerDigits will also be set to
+     * the new value.
+     * @param newValue the maximum number of integer digits to be shown; if
+     * less than zero, then zero is used. The concrete subclass may enforce an
+     * upper limit to this value appropriate to the numeric type being formatted.
+     * @see #getMaximumIntegerDigits
+     */
+    public void setMaximumIntegerDigits(int newValue) {
+        maximumIntegerDigits = Math.max(0,newValue);
+        if (minimumIntegerDigits > maximumIntegerDigits) {
+            minimumIntegerDigits = maximumIntegerDigits;
+        }
+    }
+
+    /**
+     * Returns the minimum number of digits allowed in the integer portion of a
+     * number.
+     * @see #setMinimumIntegerDigits
+     */
+    public int getMinimumIntegerDigits() {
+        return minimumIntegerDigits;
+    }
+
+    /**
+     * Sets the minimum number of digits allowed in the integer portion of a
+     * number. minimumIntegerDigits must be <= maximumIntegerDigits.  If the
+     * new value for minimumIntegerDigits exceeds the current value
+     * of maximumIntegerDigits, then maximumIntegerDigits will also be set to
+     * the new value
+     * @param newValue the minimum number of integer digits to be shown; if
+     * less than zero, then zero is used. The concrete subclass may enforce an
+     * upper limit to this value appropriate to the numeric type being formatted.
+     * @see #getMinimumIntegerDigits
+     */
+    public void setMinimumIntegerDigits(int newValue) {
+        minimumIntegerDigits = Math.max(0,newValue);
+        if (minimumIntegerDigits > maximumIntegerDigits) {
+            maximumIntegerDigits = minimumIntegerDigits;
+        }
+    }
+
+    /**
+     * Returns the maximum number of digits allowed in the fraction portion of a
+     * number.
+     * @see #setMaximumFractionDigits
+     */
+    public int getMaximumFractionDigits() {
+        return maximumFractionDigits;
+    }
+
+    /**
+     * Sets the maximum number of digits allowed in the fraction portion of a
+     * number. maximumFractionDigits must be >= minimumFractionDigits.  If the
+     * new value for maximumFractionDigits is less than the current value
+     * of minimumFractionDigits, then minimumFractionDigits will also be set to
+     * the new value.
+     * @param newValue the maximum number of fraction digits to be shown; if
+     * less than zero, then zero is used. The concrete subclass may enforce an
+     * upper limit to this value appropriate to the numeric type being formatted.
+     * @see #getMaximumFractionDigits
+     */
+    public void setMaximumFractionDigits(int newValue) {
+        maximumFractionDigits = Math.max(0,newValue);
+        if (maximumFractionDigits < minimumFractionDigits) {
+            minimumFractionDigits = maximumFractionDigits;
+        }
+    }
+
+    /**
+     * Returns the minimum number of digits allowed in the fraction portion of a
+     * number.
+     * @see #setMinimumFractionDigits
+     */
+    public int getMinimumFractionDigits() {
+        return minimumFractionDigits;
+    }
+
+    /**
+     * Sets the minimum number of digits allowed in the fraction portion of a
+     * number. minimumFractionDigits must be <= maximumFractionDigits.  If the
+     * new value for minimumFractionDigits exceeds the current value
+     * of maximumFractionDigits, then maximumIntegerDigits will also be set to
+     * the new value
+     * @param newValue the minimum number of fraction digits to be shown; if
+     * less than zero, then zero is used. The concrete subclass may enforce an
+     * upper limit to this value appropriate to the numeric type being formatted.
+     * @see #getMinimumFractionDigits
+     */
+    public void setMinimumFractionDigits(int newValue) {
+        minimumFractionDigits = Math.max(0,newValue);
+        if (maximumFractionDigits < minimumFractionDigits) {
+            maximumFractionDigits = minimumFractionDigits;
+        }
+    }
+
+    /**
+     * Gets the currency used by this number format when formatting
+     * currency values. The initial value is derived in a locale dependent
+     * way. The returned value may be null if no valid
+     * currency could be determined and no currency has been set using
+     * {@link #setCurrency(java.util.Currency) setCurrency}.
+     * <p>
+     * The default implementation throws
+     * <code>UnsupportedOperationException</code>.
+     *
+     * @return the currency used by this number format, or <code>null</code>
+     * @exception UnsupportedOperationException if the number format class
+     * doesn't implement currency formatting
+     * @since 1.4
+     */
+    public Currency getCurrency() {
+        throw new UnsupportedOperationException();
+    }
+
+    /**
+     * 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.
+     * <p>
+     * The default implementation throws
+     * <code>UnsupportedOperationException</code>.
+     *
+     * @param currency the new currency to be used by this number format
+     * @exception UnsupportedOperationException if the number format class
+     * doesn't implement currency formatting
+     * @exception NullPointerException if <code>currency</code> is null
+     * @since 1.4
+     */
+    public void setCurrency(Currency currency) {
+        throw new UnsupportedOperationException();
+    }
+
+    /**
+     * Gets the {@link java.math.RoundingMode} used in this NumberFormat.
+     * The default implementation of this method in NumberFormat
+     * always throws {@link java.lang.UnsupportedOperationException}.
+     * Subclasses which handle different rounding modes should override
+     * this method.
+     *
+     * @exception UnsupportedOperationException The default implementation
+     *     always throws this exception
+     * @return The <code>RoundingMode</code> used for this NumberFormat.
+     * @see #setRoundingMode(RoundingMode)
+     * @since 1.6
+     */
+    public RoundingMode getRoundingMode() {
+        throw new UnsupportedOperationException();
+    }
+
+    /**
+     * Sets the {@link java.math.RoundingMode} used in this NumberFormat.
+     * The default implementation of this method in NumberFormat always
+     * throws {@link java.lang.UnsupportedOperationException}.
+     * Subclasses which handle different rounding modes should override
+     * this method.
+     *
+     * @exception UnsupportedOperationException The default implementation
+     *     always throws this exception
+     * @exception NullPointerException if <code>roundingMode</code> is null
+     * @param roundingMode The <code>RoundingMode</code> to be used
+     * @see #getRoundingMode()
+     * @since 1.6
+     */
+    public void setRoundingMode(RoundingMode roundingMode) {
+        throw new UnsupportedOperationException();
+    }
+
+    // =======================privates===============================
+
+    private static NumberFormat getInstance(Locale desiredLocale,
+                                           int choice) {
+        // Check whether a provider can provide an implementation that's closer
+        // to the requested locale than what the Java runtime itself can provide.
+        LocaleServiceProviderPool pool =
+            LocaleServiceProviderPool.getPool(NumberFormatProvider.class);
+        if (pool.hasProviders()) {
+            NumberFormat providersInstance = pool.getLocalizedObject(
+                                    NumberFormatGetter.INSTANCE,
+                                    desiredLocale,
+                                    choice);
+            if (providersInstance != null) {
+                return providersInstance;
+            }
+        }
+
+        /* try the cache first */
+        String[] numberPatterns = (String[])cachedLocaleData.get(desiredLocale);
+        if (numberPatterns == null) { /* cache miss */
+            ResourceBundle resource = LocaleData.getNumberFormatData(desiredLocale);
+            numberPatterns = resource.getStringArray("NumberPatterns");
+            /* update cache */
+            cachedLocaleData.put(desiredLocale, numberPatterns);
+        }
+
+        DecimalFormatSymbols symbols = DecimalFormatSymbols.getInstance(desiredLocale);
+        int entry = (choice == INTEGERSTYLE) ? NUMBERSTYLE : choice;
+        DecimalFormat format = new DecimalFormat(numberPatterns[entry], symbols);
+
+        if (choice == INTEGERSTYLE) {
+            format.setMaximumFractionDigits(0);
+            format.setDecimalSeparatorAlwaysShown(false);
+            format.setParseIntegerOnly(true);
+        } else if (choice == CURRENCYSTYLE) {
+            format.adjustForCurrencyDefaultFractionDigits();
+        }
+
+        return format;
+    }
+
+    /**
+     * First, read in the default serializable data.
+     *
+     * Then, if <code>serialVersionOnStream</code> is less than 1, indicating that
+     * the stream was written by JDK 1.1,
+     * set the <code>int</code> fields such as <code>maximumIntegerDigits</code>
+     * to be equal to the <code>byte</code> fields such as <code>maxIntegerDigits</code>,
+     * since the <code>int</code> fields were not present in JDK 1.1.
+     * Finally, set serialVersionOnStream back to the maximum allowed value so that
+     * default serialization will work properly if this object is streamed out again.
+     *
+     * <p>If <code>minimumIntegerDigits</code> is greater than
+     * <code>maximumIntegerDigits</code> or <code>minimumFractionDigits</code>
+     * is greater than <code>maximumFractionDigits</code>, then the stream data
+     * is invalid and this method throws an <code>InvalidObjectException</code>.
+     * In addition, if any of these values is negative, then this method throws
+     * an <code>InvalidObjectException</code>.
+     *
+     * @since 1.2
+     */
+    private void readObject(ObjectInputStream stream)
+         throws IOException, ClassNotFoundException
+    {
+        stream.defaultReadObject();
+        if (serialVersionOnStream < 1) {
+            // Didn't have additional int fields, reassign to use them.
+            maximumIntegerDigits = maxIntegerDigits;
+            minimumIntegerDigits = minIntegerDigits;
+            maximumFractionDigits = maxFractionDigits;
+            minimumFractionDigits = minFractionDigits;
+        }
+        if (minimumIntegerDigits > maximumIntegerDigits ||
+            minimumFractionDigits > maximumFractionDigits ||
+            minimumIntegerDigits < 0 || minimumFractionDigits < 0) {
+            throw new InvalidObjectException("Digit count range invalid");
+        }
+        serialVersionOnStream = currentSerialVersion;
+    }
+
+    /**
+     * Write out the default serializable data, after first setting
+     * the <code>byte</code> fields such as <code>maxIntegerDigits</code> to be
+     * equal to the <code>int</code> fields such as <code>maximumIntegerDigits</code>
+     * (or to <code>Byte.MAX_VALUE</code>, whichever is smaller), for compatibility
+     * with the JDK 1.1 version of the stream format.
+     *
+     * @since 1.2
+     */
+    private void writeObject(ObjectOutputStream stream)
+         throws IOException
+    {
+        maxIntegerDigits = (maximumIntegerDigits > Byte.MAX_VALUE) ?
+                           Byte.MAX_VALUE : (byte)maximumIntegerDigits;
+        minIntegerDigits = (minimumIntegerDigits > Byte.MAX_VALUE) ?
+                           Byte.MAX_VALUE : (byte)minimumIntegerDigits;
+        maxFractionDigits = (maximumFractionDigits > Byte.MAX_VALUE) ?
+                            Byte.MAX_VALUE : (byte)maximumFractionDigits;
+        minFractionDigits = (minimumFractionDigits > Byte.MAX_VALUE) ?
+                            Byte.MAX_VALUE : (byte)minimumFractionDigits;
+        stream.defaultWriteObject();
+    }
+
+    /**
+     * Cache to hold the NumberPatterns of a Locale.
+     */
+    private static final Hashtable cachedLocaleData = new Hashtable(3);
+
+    // Constants used by factory methods to specify a style of format.
+    private static final int NUMBERSTYLE = 0;
+    private static final int CURRENCYSTYLE = 1;
+    private static final int PERCENTSTYLE = 2;
+    private static final int SCIENTIFICSTYLE = 3;
+    private static final int INTEGERSTYLE = 4;
+
+    /**
+     * True if the grouping (i.e. thousands) separator is used when
+     * formatting and parsing numbers.
+     *
+     * @serial
+     * @see #isGroupingUsed
+     */
+    private boolean groupingUsed = true;
+
+    /**
+     * The maximum number of digits allowed in the integer portion of a
+     * number.  <code>maxIntegerDigits</code> must be greater than or equal to
+     * <code>minIntegerDigits</code>.
+     * <p>
+     * <strong>Note:</strong> This field exists only for serialization
+     * compatibility with JDK 1.1.  In Java platform 2 v1.2 and higher, the new
+     * <code>int</code> field <code>maximumIntegerDigits</code> is used instead.
+     * When writing to a stream, <code>maxIntegerDigits</code> is set to
+     * <code>maximumIntegerDigits</code> or <code>Byte.MAX_VALUE</code>,
+     * whichever is smaller.  When reading from a stream, this field is used
+     * only if <code>serialVersionOnStream</code> is less than 1.
+     *
+     * @serial
+     * @see #getMaximumIntegerDigits
+     */
+    private byte    maxIntegerDigits = 40;
+
+    /**
+     * The minimum number of digits allowed in the integer portion of a
+     * number.  <code>minimumIntegerDigits</code> must be less than or equal to
+     * <code>maximumIntegerDigits</code>.
+     * <p>
+     * <strong>Note:</strong> This field exists only for serialization
+     * compatibility with JDK 1.1.  In Java platform 2 v1.2 and higher, the new
+     * <code>int</code> field <code>minimumIntegerDigits</code> is used instead.
+     * When writing to a stream, <code>minIntegerDigits</code> is set to
+     * <code>minimumIntegerDigits</code> or <code>Byte.MAX_VALUE</code>,
+     * whichever is smaller.  When reading from a stream, this field is used
+     * only if <code>serialVersionOnStream</code> is less than 1.
+     *
+     * @serial
+     * @see #getMinimumIntegerDigits
+     */
+    private byte    minIntegerDigits = 1;
+
+    /**
+     * The maximum number of digits allowed in the fractional portion of a
+     * number.  <code>maximumFractionDigits</code> must be greater than or equal to
+     * <code>minimumFractionDigits</code>.
+     * <p>
+     * <strong>Note:</strong> This field exists only for serialization
+     * compatibility with JDK 1.1.  In Java platform 2 v1.2 and higher, the new
+     * <code>int</code> field <code>maximumFractionDigits</code> is used instead.
+     * When writing to a stream, <code>maxFractionDigits</code> is set to
+     * <code>maximumFractionDigits</code> or <code>Byte.MAX_VALUE</code>,
+     * whichever is smaller.  When reading from a stream, this field is used
+     * only if <code>serialVersionOnStream</code> is less than 1.
+     *
+     * @serial
+     * @see #getMaximumFractionDigits
+     */
+    private byte    maxFractionDigits = 3;    // invariant, >= minFractionDigits
+
+    /**
+     * The minimum number of digits allowed in the fractional portion of a
+     * number.  <code>minimumFractionDigits</code> must be less than or equal to
+     * <code>maximumFractionDigits</code>.
+     * <p>
+     * <strong>Note:</strong> This field exists only for serialization
+     * compatibility with JDK 1.1.  In Java platform 2 v1.2 and higher, the new
+     * <code>int</code> field <code>minimumFractionDigits</code> is used instead.
+     * When writing to a stream, <code>minFractionDigits</code> is set to
+     * <code>minimumFractionDigits</code> or <code>Byte.MAX_VALUE</code>,
+     * whichever is smaller.  When reading from a stream, this field is used
+     * only if <code>serialVersionOnStream</code> is less than 1.
+     *
+     * @serial
+     * @see #getMinimumFractionDigits
+     */
+    private byte    minFractionDigits = 0;
+
+    /**
+     * True if this format will parse numbers as integers only.
+     *
+     * @serial
+     * @see #isParseIntegerOnly
+     */
+    private boolean parseIntegerOnly = false;
+
+    // new fields for 1.2.  byte is too small for integer digits.
+
+    /**
+     * The maximum number of digits allowed in the integer portion of a
+     * number.  <code>maximumIntegerDigits</code> must be greater than or equal to
+     * <code>minimumIntegerDigits</code>.
+     *
+     * @serial
+     * @since 1.2
+     * @see #getMaximumIntegerDigits
+     */
+    private int    maximumIntegerDigits = 40;
+
+    /**
+     * The minimum number of digits allowed in the integer portion of a
+     * number.  <code>minimumIntegerDigits</code> must be less than or equal to
+     * <code>maximumIntegerDigits</code>.
+     *
+     * @serial
+     * @since 1.2
+     * @see #getMinimumIntegerDigits
+     */
+    private int    minimumIntegerDigits = 1;
+
+    /**
+     * The maximum number of digits allowed in the fractional portion of a
+     * number.  <code>maximumFractionDigits</code> must be greater than or equal to
+     * <code>minimumFractionDigits</code>.
+     *
+     * @serial
+     * @since 1.2
+     * @see #getMaximumFractionDigits
+     */
+    private int    maximumFractionDigits = 3;    // invariant, >= minFractionDigits
+
+    /**
+     * The minimum number of digits allowed in the fractional portion of a
+     * number.  <code>minimumFractionDigits</code> must be less than or equal to
+     * <code>maximumFractionDigits</code>.
+     *
+     * @serial
+     * @since 1.2
+     * @see #getMinimumFractionDigits
+     */
+    private int    minimumFractionDigits = 0;
+
+    static final int currentSerialVersion = 1;
+
+    /**
+     * Describes the version of <code>NumberFormat</code> present on the stream.
+     * Possible values are:
+     * <ul>
+     * <li><b>0</b> (or uninitialized): the JDK 1.1 version of the stream format.
+     *     In this version, the <code>int</code> fields such as
+     *     <code>maximumIntegerDigits</code> were not present, and the <code>byte</code>
+     *     fields such as <code>maxIntegerDigits</code> are used instead.
+     *
+     * <li><b>1</b>: the 1.2 version of the stream format.  The values of the
+     *     <code>byte</code> fields such as <code>maxIntegerDigits</code> are ignored,
+     *     and the <code>int</code> fields such as <code>maximumIntegerDigits</code>
+     *     are used instead.
+     * </ul>
+     * When streaming out a <code>NumberFormat</code>, the most recent format
+     * (corresponding to the highest allowable <code>serialVersionOnStream</code>)
+     * is always written.
+     *
+     * @serial
+     * @since 1.2
+     */
+    private int serialVersionOnStream = currentSerialVersion;
+
+    // Removed "implements Cloneable" clause.  Needs to update serialization
+    // ID for backward compatibility.
+    static final long serialVersionUID = -2308460125733713944L;
+
+
+    //
+    // class for AttributedCharacterIterator attributes
+    //
+    /**
+     * Defines constants that are used as attribute keys in the
+     * <code>AttributedCharacterIterator</code> returned
+     * from <code>NumberFormat.formatToCharacterIterator</code> and as
+     * field identifiers in <code>FieldPosition</code>.
+     *
+     * @since 1.4
+     */
+    public static class Field extends Format.Field {
+
+        // Proclaim serial compatibility with 1.4 FCS
+        private static final long serialVersionUID = 7494728892700160890L;
+
+        // table of all instances in this class, used by readResolve
+        private static final Map instanceMap = new HashMap(11);
+
+        /**
+         * Creates a Field instance with the specified
+         * name.
+         *
+         * @param name Name of the attribute
+         */
+        protected Field(String name) {
+            super(name);
+            if (this.getClass() == NumberFormat.Field.class) {
+                instanceMap.put(name, this);
+            }
+        }
+
+        /**
+         * Resolves instances being deserialized to the predefined constants.
+         *
+         * @throws InvalidObjectException if the constant could not be resolved.
+         * @return resolved NumberFormat.Field constant
+         */
+        protected Object readResolve() throws InvalidObjectException {
+            if (this.getClass() != NumberFormat.Field.class) {
+                throw new InvalidObjectException("subclass didn't correctly implement readResolve");
+            }
+
+            Object instance = instanceMap.get(getName());
+            if (instance != null) {
+                return instance;
+            } else {
+                throw new InvalidObjectException("unknown attribute name");
+            }
+        }
+
+        /**
+         * Constant identifying the integer field.
+         */
+        public static final Field INTEGER = new Field("integer");
+
+        /**
+         * Constant identifying the fraction field.
+         */
+        public static final Field FRACTION = new Field("fraction");
+
+        /**
+         * Constant identifying the exponent field.
+         */
+        public static final Field EXPONENT = new Field("exponent");
+
+        /**
+         * Constant identifying the decimal separator field.
+         */
+        public static final Field DECIMAL_SEPARATOR =
+                            new Field("decimal separator");
+
+        /**
+         * Constant identifying the sign field.
+         */
+        public static final Field SIGN = new Field("sign");
+
+        /**
+         * Constant identifying the grouping separator field.
+         */
+        public static final Field GROUPING_SEPARATOR =
+                            new Field("grouping separator");
+
+        /**
+         * Constant identifying the exponent symbol field.
+         */
+        public static final Field EXPONENT_SYMBOL = new
+                            Field("exponent symbol");
+
+        /**
+         * Constant identifying the percent field.
+         */
+        public static final Field PERCENT = new Field("percent");
+
+        /**
+         * Constant identifying the permille field.
+         */
+        public static final Field PERMILLE = new Field("per mille");
+
+        /**
+         * Constant identifying the currency field.
+         */
+        public static final Field CURRENCY = new Field("currency");
+
+        /**
+         * Constant identifying the exponent sign field.
+         */
+        public static final Field EXPONENT_SIGN = new Field("exponent sign");
+    }
+
+    /**
+     * Obtains a NumberFormat instance from a NumberFormatProvider implementation.
+     */
+    private static class NumberFormatGetter
+        implements LocaleServiceProviderPool.LocalizedObjectGetter<NumberFormatProvider,
+                                                                   NumberFormat> {
+        private static final NumberFormatGetter INSTANCE = new NumberFormatGetter();
+
+        public NumberFormat getObject(NumberFormatProvider numberFormatProvider,
+                                Locale locale,
+                                String key,
+                                Object... params) {
+            assert params.length == 1;
+            int choice = (Integer)params[0];
+
+            switch (choice) {
+            case NUMBERSTYLE:
+                return numberFormatProvider.getNumberInstance(locale);
+            case PERCENTSTYLE:
+                return numberFormatProvider.getPercentInstance(locale);
+            case CURRENCYSTYLE:
+                return numberFormatProvider.getCurrencyInstance(locale);
+            case INTEGERSTYLE:
+                return numberFormatProvider.getIntegerInstance(locale);
+            default:
+                assert false : choice;
+            }
+
+            return null;
+        }
+    }
+}