java.text
Class NumberFormat

java.lang.Object
  java.text.Format
      java.text.NumberFormat

All Implemented Interfaces:

Cloneable, Serializable

Direct Known Subclasses:

ChoiceFormat, DecimalFormat

public abstract class NumberFormat

extends Format

NumberFormat is the abstract base class for all number formats. This class provides the interface for formatting and parsing numbers. NumberFormat also provides methods for determining which locales have number formats, and what their names are.

NumberFormat 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.

To format a number for the current Locale, use one of the factory class methods:

  myString = NumberFormat.getInstance().format(myNumber);
 

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.

 NumberFormat nf = NumberFormat.getInstance();
 for (int i = 0; i < a.length; ++i) {
     output.println(nf.format(myNumber[i]) + "; ");
 }
 

To format a number for a different Locale, specify it in the call to getInstance.

 NumberFormat nf = NumberFormat.getInstance(Locale.FRENCH);
 

You can also use a NumberFormat to parse numbers:

 myNumber = nf.parse(myString);
 

Use getInstance or getNumberInstance to get the normal number format. Use getIntegerInstance to get an integer number format. Use getCurrencyInstance to get the currency number format. And use getPercentInstance to get a format for displaying percentages. With this format, a fraction like 0.53 is displayed as 53%.

You can also control the display of numbers with such methods as setMinimumFractionDigits. If you want even more control over the format or parsing, or want to give your users more control, you can try casting the NumberFormat you get from the factory methods to a DecimalFormat. This will work for the vast majority of locales; just remember to put it in a try block in case you encounter an unusual one.

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,

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.

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.

You can also use forms of the parse and format methods with ParsePosition and FieldPosition to allow you to:

• progressively parse through pieces of a string
• align the decimal point and other areas

For example, you can align numbers in two ways:

1. If you are using a monospaced font with spacing for alignment, you can pass the FieldPosition in your format call, with field = INTEGER_FIELD. On output, getEndIndex 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.
2. If you are using proportional fonts, instead of padding with spaces, measure the width of the string in pixels from the start to getEndIndex. 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.

Synchronization

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.

Author:

Mark Davis, Helena Shih

See Also:

DecimalFormat, ChoiceFormat, Serialized Form

Nested Class Summary

static class

NumberFormat.Field Defines constants that are used as attribute keys in the AttributedCharacterIterator returned from NumberFormat.formatToCharacterIterator and as field identifiers in FieldPosition.

Nested classes inherited from class java.text.Format

Format.FieldDelegate

Field Summary

private static Hashtable	cachedLocaleData Cache to hold the NumberPatterns of a Locale.
private static int	CURRENCYSTYLE
(package private) static int	currentSerialVersion
static int	FRACTION_FIELD Field constant used to construct a FieldPosition object.
private boolean	groupingUsed True if the the grouping (i.e. thousands) separator is used when formatting and parsing numbers.
static int	INTEGER_FIELD Field constant used to construct a FieldPosition object.
private static int	INTEGERSTYLE
private byte	maxFractionDigits The maximum number of digits allowed in the fractional portion of a number.
private int	maximumFractionDigits The maximum number of digits allowed in the fractional portion of a number.
private int	maximumIntegerDigits The maximum number of digits allowed in the integer portion of a number.
private byte	maxIntegerDigits The maximum number of digits allowed in the integer portion of a number.
private byte	minFractionDigits The minimum number of digits allowed in the fractional portion of a number.
private int	minimumFractionDigits The minimum number of digits allowed in the fractional portion of a number.
private int	minimumIntegerDigits The minimum number of digits allowed in the integer portion of a number.
private byte	minIntegerDigits The minimum number of digits allowed in the integer portion of a number.
private static int	NUMBERSTYLE
private boolean	parseIntegerOnly True if this format will parse numbers as integers only.
private static int	PERCENTSTYLE
private static int	SCIENTIFICSTYLE
private int	serialVersionOnStream Describes the version of NumberFormat present on the stream.
(package private) static long	serialVersionUID

Constructor Summary

NumberFormat()

Method Summary

Object	clone() Overrides Cloneable
boolean	equals(Object obj) Overrides equals
String	format(double number) Specialization of format.
abstract StringBuffer	format(double number, StringBuffer toAppendTo, FieldPosition pos) Specialization of format.
String	format(long number) Specialization of format.
abstract StringBuffer	format(long number, StringBuffer toAppendTo, FieldPosition pos) Specialization of format.
StringBuffer	format(Object number, StringBuffer toAppendTo, FieldPosition pos) Formats an object to produce a string.
static Locale[]	getAvailableLocales() Get the set of Locales for which NumberFormats are installed
Currency	getCurrency() Gets the currency used by this number format when formatting currency values.
static NumberFormat	getCurrencyInstance() Returns a currency format for the current default locale.
static NumberFormat	getCurrencyInstance(Locale inLocale) Returns a currency format for the specified locale.
static NumberFormat	getInstance() Returns the default number format for the current default locale.
static NumberFormat	getInstance(Locale inLocale) Returns the default number format for the specified locale.
private static NumberFormat	getInstance(Locale desiredLocale, int choice)
static NumberFormat	getIntegerInstance() Returns an integer number format for the current default locale.
static NumberFormat	getIntegerInstance(Locale inLocale) Returns an integer number format for the specified locale.
int	getMaximumFractionDigits() Returns the maximum number of digits allowed in the fraction portion of a number.
int	getMaximumIntegerDigits() Returns the maximum number of digits allowed in the integer portion of a number.
int	getMinimumFractionDigits() Returns the minimum number of digits allowed in the fraction portion of a number.
int	getMinimumIntegerDigits() Returns the minimum number of digits allowed in the integer portion of a number.
static NumberFormat	getNumberInstance() Returns a general-purpose number format for the current default locale.
static NumberFormat	getNumberInstance(Locale inLocale) Returns a general-purpose number format for the specified locale.
static NumberFormat	getPercentInstance() Returns a percentage format for the current default locale.
static NumberFormat	getPercentInstance(Locale inLocale) Returns a percentage format for the specified locale.
(package private) static NumberFormat	getScientificInstance() Returns a scientific format for the current default locale.
(package private) static NumberFormat	getScientificInstance(Locale inLocale) Returns a scientific format for the specified locale.
int	hashCode() Overrides hashCode
boolean	isGroupingUsed() Returns true if grouping is used in this format.
boolean	isParseIntegerOnly() Returns true if this format will parse numbers as integers only.
Number	parse(String source) Parses text from the beginning of the given string to produce a number.
abstract Number	parse(String source, ParsePosition parsePosition) Returns a Long if possible (e.g., within the range [Long.MIN_VALUE, Long.MAX_VALUE] and with no decimals), otherwise a Double.
Object	parseObject(String source, ParsePosition pos) Parses text from a string to produce a Number.
private void	readObject(ObjectInputStream stream) First, read in the default serializable data.
void	setCurrency(Currency currency) Sets the currency used by this number format when formatting currency values.
void	setGroupingUsed(boolean newValue) Set whether or not grouping will be used in this format.
void	setMaximumFractionDigits(int newValue) Sets the maximum number of digits allowed in the fraction portion of a number. maximumFractionDigits must be >= minimumFractionDigits.
void	setMaximumIntegerDigits(int newValue) Sets the maximum number of digits allowed in the integer portion of a number. maximumIntegerDigits must be >= minimumIntegerDigits.
void	setMinimumFractionDigits(int newValue) Sets the minimum number of digits allowed in the fraction portion of a number. minimumFractionDigits must be <= maximumFractionDigits.
void	setMinimumIntegerDigits(int newValue) Sets the minimum number of digits allowed in the integer portion of a number. minimumIntegerDigits must be <= maximumIntegerDigits.
void	setParseIntegerOnly(boolean value) Sets whether or not numbers should be parsed as integers only.
private void	writeObject(ObjectOutputStream stream) Write out the default serializable data, after first setting the byte fields such as maxIntegerDigits to be equal to the int fields such as maximumIntegerDigits (or to Byte.MAX_VALUE, whichever is smaller), for compatibility with the JDK 1.1 version of the stream format.

Methods inherited from class java.text.Format

createAttributedCharacterIterator, createAttributedCharacterIterator, createAttributedCharacterIterator, createAttributedCharacterIterator, format, formatToCharacterIterator, parseObject

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Field Detail

INTEGER_FIELD

public static final int INTEGER_FIELD

Field constant used to construct a FieldPosition object. Signifies that the position of the integer part of a formatted number should be returned.

See Also:

FieldPosition, Constant Field Values

FRACTION_FIELD

public static final int FRACTION_FIELD

Field constant used to construct a FieldPosition object. Signifies that the position of the fraction part of a formatted number should be returned.

See Also:

FieldPosition, Constant Field Values

cachedLocaleData

private static final Hashtable cachedLocaleData

Cache to hold the NumberPatterns of a Locale.

NUMBERSTYLE

private static final int NUMBERSTYLE

See Also:

Constant Field Values

CURRENCYSTYLE

private static final int CURRENCYSTYLE

See Also:

Constant Field Values

PERCENTSTYLE

private static final int PERCENTSTYLE

See Also:

Constant Field Values

SCIENTIFICSTYLE

private static final int SCIENTIFICSTYLE

See Also:

Constant Field Values

INTEGERSTYLE

private static final int INTEGERSTYLE

See Also:

Constant Field Values

groupingUsed

private boolean groupingUsed

True if the the grouping (i.e. thousands) separator is used when formatting and parsing numbers.

See Also:

isGroupingUsed()

maxIntegerDigits

private byte maxIntegerDigits

The maximum number of digits allowed in the integer portion of a number. maxIntegerDigits must be greater than or equal to minIntegerDigits.

Note: This field exists only for serialization compatibility with JDK 1.1. In Java platform 2 v1.2 and higher, the new int field maximumIntegerDigits is used instead. When writing to a stream, maxIntegerDigits is set to maximumIntegerDigits or Byte.MAX_VALUE, whichever is smaller. When reading from a stream, this field is used only if serialVersionOnStream is less than 1.

See Also:

getMaximumIntegerDigits()

minIntegerDigits

private byte minIntegerDigits

The minimum number of digits allowed in the integer portion of a number. minimumIntegerDigits must be less than or equal to maximumIntegerDigits.

Note: This field exists only for serialization compatibility with JDK 1.1. In Java platform 2 v1.2 and higher, the new int field minimumIntegerDigits is used instead. When writing to a stream, minIntegerDigits is set to minimumIntegerDigits or Byte.MAX_VALUE, whichever is smaller. When reading from a stream, this field is used only if serialVersionOnStream is less than 1.

See Also:

getMinimumIntegerDigits()

maxFractionDigits

private byte maxFractionDigits

The maximum number of digits allowed in the fractional portion of a number. maximumFractionDigits must be greater than or equal to minimumFractionDigits.

Note: This field exists only for serialization compatibility with JDK 1.1. In Java platform 2 v1.2 and higher, the new int field maximumFractionDigits is used instead. When writing to a stream, maxFractionDigits is set to maximumFractionDigits or Byte.MAX_VALUE, whichever is smaller. When reading from a stream, this field is used only if serialVersionOnStream is less than 1.

See Also:

getMaximumFractionDigits()

minFractionDigits

private byte minFractionDigits

The minimum number of digits allowed in the fractional portion of a number. minimumFractionDigits must be less than or equal to maximumFractionDigits.

Note: This field exists only for serialization compatibility with JDK 1.1. In Java platform 2 v1.2 and higher, the new int field minimumFractionDigits is used instead. When writing to a stream, minFractionDigits is set to minimumFractionDigits or Byte.MAX_VALUE, whichever is smaller. When reading from a stream, this field is used only if serialVersionOnStream is less than 1.

See Also:

getMinimumFractionDigits()

parseIntegerOnly

private boolean parseIntegerOnly

True if this format will parse numbers as integers only.

See Also:

isParseIntegerOnly()

maximumIntegerDigits

private int maximumIntegerDigits

The maximum number of digits allowed in the integer portion of a number. maximumIntegerDigits must be greater than or equal to minimumIntegerDigits.

Since:

1.2

See Also:

getMaximumIntegerDigits()

minimumIntegerDigits

private int minimumIntegerDigits

The minimum number of digits allowed in the integer portion of a number. minimumIntegerDigits must be less than or equal to maximumIntegerDigits.

Since:

1.2

See Also:

getMinimumIntegerDigits()

maximumFractionDigits

private int maximumFractionDigits

The maximum number of digits allowed in the fractional portion of a number. maximumFractionDigits must be greater than or equal to minimumFractionDigits.

Since:

1.2

See Also:

getMaximumFractionDigits()

minimumFractionDigits

private int minimumFractionDigits

The minimum number of digits allowed in the fractional portion of a number. minimumFractionDigits must be less than or equal to maximumFractionDigits.

Since:

1.2

See Also:

getMinimumFractionDigits()

currentSerialVersion

static final int currentSerialVersion

See Also:

Constant Field Values

serialVersionOnStream

private int serialVersionOnStream

Describes the version of NumberFormat present on the stream. Possible values are:

• 0 (or uninitialized): the JDK 1.1 version of the stream format. In this version, the int fields such as maximumIntegerDigits were not present, and the byte fields such as maxIntegerDigits are used instead.
• 1: the 1.2 version of the stream format. The values of the byte fields such as maxIntegerDigits are ignored, and the int fields such as maximumIntegerDigits are used instead.

When streaming out a NumberFormat, the most recent format (corresponding to the highest allowable serialVersionOnStream) is always written.

Since:

1.2

serialVersionUID

static final long serialVersionUID

See Also:

Constant Field Values

Constructor Detail

NumberFormat

public NumberFormat()

Method Detail

format

public final StringBuffer format(Object number,
                                 StringBuffer toAppendTo,
                                 FieldPosition pos)

Formats an object to produce a string. This general routines allows polymorphic parsing and formatting for objects.

Specified by:

format in class Format

Parameters:

number - the object to format

toAppendTo - where the text is to be appended

pos - On input: an alignment field, if desired. On output: the offsets of the alignment field.

Returns:

the value passed in as toAppendTo (this allows chaining, as with StringBuffer.append())

Throws:

IllegalArgumentException - when the Format cannot format the given object.

See Also:

FieldPosition

parseObject

public final Object parseObject(String source,
                                ParsePosition pos)

Parses text from a string to produce a Number.

The method attempts to parse text starting at the index given by pos. If parsing succeeds, then the index of pos 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 pos can be used to indicate the starting point for the next call to this method. If an error occurs, then the index of pos is not changed, the error index of pos is set to the index of the character where the error occurred, and null is returned.

See the parse(String, ParsePosition) method for more information on number parsing.

Specified by:

parseObject in class Format

Parameters:

source - A String, part of which should be parsed.

pos - A ParsePosition object with index and error index information as described above.

Returns:

A Number parsed from the string. In case of error, returns null.

Throws:

NullPointerException - if pos is null.

format

public final String format(double number)

Specialization of format.

See Also:

Format.format(java.lang.Object)

format

public final String format(long number)

Specialization of format.

See Also:

Format.format(java.lang.Object)

format

public abstract StringBuffer format(double number,
                                    StringBuffer toAppendTo,
                                    FieldPosition pos)

Specialization of format.

See Also:

Format.format(java.lang.Object)

format

public abstract StringBuffer format(long number,
                                    StringBuffer toAppendTo,
                                    FieldPosition pos)

Specialization of format.

See Also:

Format.format(java.lang.Object)

parse

public abstract Number parse(String source,
                             ParsePosition parsePosition)

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 Also:

isParseIntegerOnly(), Format.parseObject(java.lang.String, java.text.ParsePosition)

parse

public Number parse(String source)
             throws ParseException

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.

See the parse(String, ParsePosition) method for more information on number parsing.

Parameters:

source - A String whose beginning should be parsed.

Returns:

A Number parsed from the string.

Throws:

ParseException - if the beginning of the specified string cannot be parsed.

isParseIntegerOnly

public boolean isParseIntegerOnly()

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.

setParseIntegerOnly

public void setParseIntegerOnly(boolean value)

Sets whether or not numbers should be parsed as integers only.

See Also:

isParseIntegerOnly()

getInstance

public static final NumberFormat getInstance()

Returns the default number format for the current default locale. The default format is one of the styles provided by the other factory methods: getNumberInstance, getIntegerInstance, getCurrencyInstance or getPercentInstance. Exactly which one is locale dependant.

getInstance

public static NumberFormat getInstance(Locale inLocale)

Returns the default number format for the specified locale. The default format is one of the styles provided by the other factory methods: getNumberInstance, getIntegerInstance, getCurrencyInstance or getPercentInstance. Exactly which one is locale dependant.

getNumberInstance

public static final NumberFormat getNumberInstance()

Returns a general-purpose number format for the current default locale.

getNumberInstance

public static NumberFormat getNumberInstance(Locale inLocale)

Returns a general-purpose number format for the specified locale.

getIntegerInstance

public static final NumberFormat getIntegerInstance()

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 IEEE half-even rounding (see ROUND_HALF_EVEN) for formatting, and to parse only the integer part of an input string (see isParseIntegerOnly).

Returns:

a number format for integer values

Since:

1.4

getIntegerInstance

public static NumberFormat getIntegerInstance(Locale inLocale)

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 IEEE half-even rounding (see ROUND_HALF_EVEN) for formatting, and to parse only the integer part of an input string (see isParseIntegerOnly).

Parameters:

inLocale - the locale for which a number format is needed

Returns:

a number format for integer values

Since:

1.4

getCurrencyInstance

public static final NumberFormat getCurrencyInstance()

Returns a currency format for the current default locale.

getCurrencyInstance

public static NumberFormat getCurrencyInstance(Locale inLocale)

Returns a currency format for the specified locale.

getPercentInstance

public static final NumberFormat getPercentInstance()

Returns a percentage format for the current default locale.

getPercentInstance

public static NumberFormat getPercentInstance(Locale inLocale)

Returns a percentage format for the specified locale.

getScientificInstance

static final NumberFormat getScientificInstance()

Returns a scientific format for the current default locale.

getScientificInstance

static NumberFormat getScientificInstance(Locale inLocale)

Returns a scientific format for the specified locale.

getAvailableLocales

public static Locale[] getAvailableLocales()

Get the set of Locales for which NumberFormats are installed

Returns:

available locales

hashCode

public int hashCode()

Overrides hashCode

Overrides:

hashCode in class Object

Returns:

a hash code value for this object.

See Also:

Object.equals(java.lang.Object), Hashtable

equals

public boolean equals(Object obj)

Overrides equals

Overrides:

equals in class Object

Parameters:

obj - the reference object with which to compare.

Returns:

true if this object is the same as the obj argument; false otherwise.

See Also:

Object.hashCode(), Hashtable

clone

public Object clone()

Overrides Cloneable

Overrides:

clone in class Format

Returns:

a clone of this instance.

isGroupingUsed

public boolean isGroupingUsed()

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 Also:

setGroupingUsed(boolean)

setGroupingUsed

public void setGroupingUsed(boolean newValue)

Set whether or not grouping will be used in this format.

See Also:

isGroupingUsed()

getMaximumIntegerDigits

public int getMaximumIntegerDigits()

Returns the maximum number of digits allowed in the integer portion of a number.

See Also:

setMaximumIntegerDigits(int)

setMaximumIntegerDigits

public void setMaximumIntegerDigits(int newValue)

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.

Parameters:

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 Also:

getMaximumIntegerDigits()

getMinimumIntegerDigits

public int getMinimumIntegerDigits()

Returns the minimum number of digits allowed in the integer portion of a number.

See Also:

setMinimumIntegerDigits(int)

setMinimumIntegerDigits

public void setMinimumIntegerDigits(int newValue)

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

Parameters:

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 Also:

getMinimumIntegerDigits()

getMaximumFractionDigits

public int getMaximumFractionDigits()

Returns the maximum number of digits allowed in the fraction portion of a number.

See Also:

setMaximumFractionDigits(int)

setMaximumFractionDigits

public void setMaximumFractionDigits(int newValue)

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.

Parameters:

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 Also:

getMaximumFractionDigits()

getMinimumFractionDigits

public int getMinimumFractionDigits()

Returns the minimum number of digits allowed in the fraction portion of a number.

See Also:

setMinimumFractionDigits(int)

setMinimumFractionDigits

public void setMinimumFractionDigits(int newValue)

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

Parameters:

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 Also:

getMinimumFractionDigits()

getCurrency

public Currency getCurrency()

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 setCurrency.

The default implementation throws UnsupportedOperationException.

Returns:

the currency used by this number format, or null

Throws:

UnsupportedOperationException - if the number format class doesn't implement currency formatting

Since:

1.4

setCurrency

public void setCurrency(Currency currency)

Sets the currency used by this number format when formatting currency values. This does not update the minimum or maximum number of fraction digits used by the number format.

The default implementation throws UnsupportedOperationException.

Parameters:

currency - the new currency to be used by this number format

Throws:

UnsupportedOperationException - if the number format class doesn't implement currency formatting

NullPointerException - if currency is null

Since:

1.4

getInstance

private static NumberFormat getInstance(Locale desiredLocale,
                                        int choice)

readObject

private void readObject(ObjectInputStream stream)
                 throws IOException,
                        ClassNotFoundException

First, read in the default serializable data. Then, if serialVersionOnStream is less than 1, indicating that the stream was written by JDK 1.1, set the int fields such as maximumIntegerDigits to be equal to the byte fields such as maxIntegerDigits, since the int 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.

If minimumIntegerDigits is greater than maximumIntegerDigits or minimumFractionDigits is greater than maximumFractionDigits, then the stream data is invalid and this method throws an InvalidObjectException. In addition, if any of these values is negative, then this method throws an InvalidObjectException.

Throws:

IOException

ClassNotFoundException

Since:

1.2

writeObject

private void writeObject(ObjectOutputStream stream)
                  throws IOException

Write out the default serializable data, after first setting the byte fields such as maxIntegerDigits to be equal to the int fields such as maximumIntegerDigits (or to Byte.MAX_VALUE, whichever is smaller), for compatibility with the JDK 1.1 version of the stream format.

Throws:

IOException

Since:

1.2