numberformat.java

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     * 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 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 {
        // 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");
    }
}