public class

DecimalFormat

extends NumberFormat
java.lang.Object
   ↳ java.text.Format
     ↳ java.text.NumberFormat
       ↳ java.text.DecimalFormat

Class Overview

A concrete subclass of NumberFormat that formats decimal numbers. It has a variety of features designed to make it possible to parse and format numbers in any locale, including support for Western, Arabic, or Indic digits. It also supports different flavors of numbers, including integers ("123"), fixed-point numbers ("123.4"), scientific notation ("1.23E4"), percentages ("12%"), and currency amounts ("$123"). All of these flavors can be easily localized.

This is an enhanced version of DecimalFormat that is based on the standard version in the RI. New or changed functionality is labeled NEW.

To obtain a NumberFormat for a specific locale (including the default locale), call one of NumberFormat's factory methods such as NumberFormat.getInstance. Do not call the DecimalFormat constructors directly, unless you know what you are doing, since the NumberFormat factory methods may return subclasses other than DecimalFormat. If you need to customize the format object, do something like this:

 NumberFormat f = NumberFormat.getInstance(loc);
 if (f instanceof DecimalFormat) {
     ((DecimalFormat)f).setDecimalSeparatorAlwaysShown(true);
 }
 
Example:
 // Print out a number using the localized number, currency,
 // and percent format for each locale
 Locale[] locales = NumberFormat.getAvailableLocales();
 double myNumber = -1234.56;
 NumberFormat format;
 for (int j = 0; j < 3; ++j) {
     System.out.println("FORMAT");
     for (int i = 0; i < locales.length; ++i) {
         if (locales[i].getCountry().length() == 0) {
             // Skip language-only locales
             continue;
         }
         System.out.print(locales[i].getDisplayName());
         switch (j) {
             case 0:
                 format = NumberFormat.getInstance(locales[i]);
                 break;
             case 1:
                 format = NumberFormat.getCurrencyInstance(locales[i]);
                 break;
             default:
                 format = NumberFormat.getPercentInstance(locales[i]);
                 break;
         }
         try {
             // Assume format is a DecimalFormat
             System.out.print(": "; + ((DecimalFormat)format).toPattern() + " -> "
                     + form.format(myNumber));
         } catch (Exception e) {
         }
         try {
             System.out.println(" -> " + format.parse(form.format(myNumber)));
         } catch (ParseException e) {
         }
     }
 }
 

Patterns

A DecimalFormat consists of a pattern and a set of symbols. The pattern may be set directly using applyPattern(String), or indirectly using other API methods which manipulate aspects of the pattern, such as the minimum number of integer digits. The symbols are stored in a DecimalFormatSymbols object. When using the NumberFormat factory methods, the pattern and symbols are read from ICU's locale data.

Special Pattern Characters

Many characters in a pattern are taken literally; they are matched during parsing and are written out unchanged during formatting. On the other hand, special characters stand for other characters, strings, or classes of characters. For example, the '#' character is replaced by a localized digit. Often the replacement character is the same as the pattern character; in the U.S. locale, the ',' grouping character is replaced by ','. However, the replacement is still happening, and if the symbols are modified, the grouping character changes. Some special characters affect the behavior of the formatter by their presence; for example, if the percent character is seen, then the value is multiplied by 100 before being displayed.

To insert a special character in a pattern as a literal, that is, without any special meaning, the character must be quoted. There are some exceptions to this which are noted below.

The characters listed here are used in non-localized patterns. Localized patterns use the corresponding characters taken from this formatter's DecimalFormatSymbols object instead, and these characters lose their special status. Two exceptions are the currency sign and quote, which are not localized.

Symbol Location Localized? Meaning
0 Number Yes Digit.
@ Number No NEW  Significant digit.
# Number Yes Digit, leading zeroes are not shown.
. Number Yes Decimal separator or monetary decimal separator.
- Number Yes Minus sign.
, Number Yes Grouping separator.
E Number Yes Separates mantissa and exponent in scientific notation. Does not need to be quoted in prefix or suffix.
+ Exponent Yes NEW  Prefix positive exponents with localized plus sign. Does not need to be quoted in prefix or suffix.
; Subpattern boundary Yes Separates positive and negative subpatterns.
% Prefix or suffix Yes Multiply by 100 and show as percentage.
ä (\u2030) Prefix or suffix Yes Multiply by 1000 and show as per mille.
¤ (\u00A4) Prefix or suffix No Currency sign, replaced by currency symbol. If doubled, replaced by international currency symbol. If present in a pattern, the monetary decimal separator is used instead of the decimal separator.
' Prefix or suffix No Used to quote special characters in a prefix or suffix, for example, "'#'#" formats 123 to "#123". To create a single quote itself, use two in a row: "# o''clock".
* Prefix or suffix boundary Yes NEW  Pad escape, precedes pad character.

A DecimalFormat pattern contains a postive and negative subpattern, for example, "#,##0.00;(#,##0.00)". Each subpattern has a prefix, a numeric part and a suffix. If there is no explicit negative subpattern, the negative subpattern is the localized minus sign prefixed to the positive subpattern. That is, "0.00" alone is equivalent to "0.00;-0.00". If there is an explicit negative subpattern, it serves only to specify the negative prefix and suffix; the number of digits, minimal digits, and other characteristics are ignored in the negative subpattern. This means that "#,##0.0#;(#)" produces precisely the same result as "#,##0.0#;(#,##0.0#)".

The prefixes, suffixes, and various symbols used for infinity, digits, thousands separators, decimal separators, etc. may be set to arbitrary values, and they will appear properly during formatting. However, care must be taken that the symbols and strings do not conflict, or parsing will be unreliable. For example, either the positive and negative prefixes or the suffixes must be distinct for parse(String) to be able to distinguish positive from negative values. Another example is that the decimal separator and thousands separator should be distinct characters, or parsing will be impossible.

The grouping separator is a character that separates clusters of integer digits to make large numbers more legible. It is commonly used for thousands, but in some locales it separates ten-thousands. The grouping size is the number of digits between the grouping separators, such as 3 for "100,000,000" or 4 for "1 0000 0000". There are actually two different grouping sizes: One used for the least significant integer digits, the primary grouping size, and one used for all others, the secondary grouping size. In most locales these are the same, but sometimes they are different. For example, if the primary grouping interval is 3, and the secondary is 2, then this corresponds to the pattern "#,##,##0", and the number 123456789 is formatted as "12,34,56,789". If a pattern contains multiple grouping separators, the interval between the last one and the end of the integer defines the primary grouping size, and the interval between the last two defines the secondary grouping size. All others are ignored, so "#,##,###,####", "###,###,####" and "##,#,###,####" produce the same result.

Illegal patterns, such as "#.#.#" or "#.###,###", will cause DecimalFormat to throw an IllegalArgumentException with a message that describes the problem.

Pattern BNF

 pattern    := subpattern (';' subpattern)?
 subpattern := prefix? number exponent? suffix?
 number     := (integer ('.' fraction)?) | sigDigits
 prefix     := '\\u0000'..'\\uFFFD' - specialCharacters
 suffix     := '\\u0000'..'\\uFFFD' - specialCharacters
 integer    := '#'* '0'* '0'
 fraction   := '0'* '#'*
 sigDigits  := '#'* '@' '@'* '#'*
 exponent   := 'E' '+'? '0'* '0'
 padSpec    := '*' padChar
 padChar    := '\\u0000'..'\\uFFFD' - quote
  
 Notation:
   X*       0 or more instances of X
   X?       0 or 1 instances of X
   X|Y      either X or Y
   C..D     any character from C up to D, inclusive
   S-T      characters in S, except those in T
 
The first subpattern is for positive numbers. The second (optional) subpattern is for negative numbers.

Not indicated in the BNF syntax above:

  • The grouping separator ',' can occur inside the integer and sigDigits elements, between any two pattern characters of that element, as long as the integer or sigDigits element is not followed by the exponent element.
  • NEW  Two grouping intervals are recognized: The one between the decimal point and the first grouping symbol and the one between the first and second grouping symbols. These intervals are identical in most locales, but in some locales they differ. For example, the pattern "#,##,###" formats the number 123456789 as "12,34,56,789".
  • NEW  The pad specifier padSpec may appear before the prefix, after the prefix, before the suffix, after the suffix or not at all.

Parsing

DecimalFormat parses all Unicode characters that represent decimal digits, as defined by digit(int, int). In addition, DecimalFormat also recognizes as digits the ten consecutive characters starting with the localized zero digit defined in the DecimalFormatSymbols object. During formatting, the DecimalFormatSymbols-based digits are written out.

During parsing, grouping separators are ignored.

If parse(String, ParsePosition) fails to parse a string, it returns null and leaves the parse position unchanged.

Formatting

Formatting is guided by several parameters, all of which can be specified either using a pattern or using the API. The following description applies to formats that do not use scientific notation or significant digits.

  • If the number of actual integer digits exceeds the maximum integer digits, then only the least significant digits are shown. For example, 1997 is formatted as "97" if maximum integer digits is set to 2.
  • If the number of actual integer digits is less than the minimum integer digits, then leading zeros are added. For example, 1997 is formatted as "01997" if minimum integer digits is set to 5.
  • If the number of actual fraction digits exceeds the maximum fraction digits, then half-even rounding is performed to the maximum fraction digits. For example, 0.125 is formatted as "0.12" if the maximum fraction digits is 2.
  • If the number of actual fraction digits is less than the minimum fraction digits, then trailing zeros are added. For example, 0.125 is formatted as "0.1250" if the mimimum fraction digits is set to 4.
  • Trailing fractional zeros are not displayed if they occur j positions after the decimal, where j is less than the maximum fraction digits. For example, 0.10004 is formatted as "0.1" if the maximum fraction digits is four or less.

Special Values

NaN is represented as a single character, typically \uFFFD. This character is determined by the DecimalFormatSymbols object. This is the only value for which the prefixes and suffixes are not used.

Infinity is represented as a single character, typically \u221E, with the positive or negative prefixes and suffixes applied. The infinity character is determined by the DecimalFormatSymbols object.

Scientific Notation

Numbers in scientific notation are expressed as the product of a mantissa and a power of ten, for example, 1234 can be expressed as 1.234 x 103. The mantissa is typically in the half-open interval [1.0, 10.0) or sometimes [0.0, 1.0), but it does not need to be. DecimalFormat supports arbitrary mantissas. DecimalFormat can be instructed to use scientific notation through the API or through the pattern. In a pattern, the exponent character immediately followed by one or more digit characters indicates scientific notation. Example: "0.###E0" formats the number 1234 as "1.234E3".

  • The number of digit characters after the exponent character gives the minimum exponent digit count. There is no maximum. Negative exponents are formatted using the localized minus sign, not the prefix and suffix from the pattern. This allows patterns such as "0.###E0 m/s". To prefix positive exponents with a localized plus sign, specify '+' between the exponent and the digits: "0.###E+0" will produce formats "1E+1", "1E+0", "1E-1", etc. (In localized patterns, use the localized plus sign rather than '+'.)
  • The minimum number of integer digits is achieved by adjusting the exponent. Example: 0.00123 formatted with "00.###E0" yields "12.3E-4". This only happens if there is no maximum number of integer digits. If there is a maximum, then the minimum number of integer digits is fixed at one.
  • The maximum number of integer digits, if present, specifies the exponent grouping. The most common use of this is to generate engineering notation, in which the exponent is a multiple of three, e.g., "##0.###E0". The number 12345 is formatted using "##0.###E0" as "12.345E3".
  • When using scientific notation, the formatter controls the digit counts using significant digits logic. The maximum number of significant digits limits the total number of integer and fraction digits that will be shown in the mantissa; it does not affect parsing. For example, 12345 formatted with "##0.##E0" is "12.3E3". See the section on significant digits for more details.
  • The number of significant digits shown is determined as follows: If no significant digits are used in the pattern then the minimum number of significant digits shown is one, the maximum number of significant digits shown is the sum of the minimum integer and maximum fraction digits, and it is unaffected by the maximum integer digits. If this sum is zero, then all significant digits are shown. If significant digits are used in the pattern then the number of integer digits is fixed at one and there is no exponent grouping.
  • Exponential patterns may not contain grouping separators.

NEW  Significant Digits

DecimalFormat has two ways of controlling how many digits are shown: (a) significant digit counts or (b) integer and fraction digit counts. Integer and fraction digit counts are described above. When a formatter uses significant digits counts, the number of integer and fraction digits is not specified directly, and the formatter settings for these counts are ignored. Instead, the formatter uses as many integer and fraction digits as required to display the specified number of significant digits.

Examples:
Pattern Minimum significant digits Maximum significant digits Number Output of format()
@@@ 3 3 12345 12300
@@@ 3 3 0.12345 0.123
@@## 2 4 3.14159 3.142
@@## 2 4 1.23004 1.23
  • Significant digit counts may be expressed using patterns that specify a minimum and maximum number of significant digits. These are indicated by the '@' and '#' characters. The minimum number of significant digits is the number of '@' characters. The maximum number of significant digits is the number of '@' characters plus the number of '#' characters following on the right. For example, the pattern "@@@" indicates exactly 3 significant digits. The pattern "@##" indicates from 1 to 3 significant digits. Trailing zero digits to the right of the decimal separator are suppressed after the minimum number of significant digits have been shown. For example, the pattern "@##" formats the number 0.1203 as "0.12".
  • If a pattern uses significant digits, it may not contain a decimal separator, nor the '0' pattern character. Patterns such as "@00" or "@.###" are disallowed.
  • Any number of '#' characters may be prepended to the left of the leftmost '@' character. These have no effect on the minimum and maximum significant digit counts, but may be used to position grouping separators. For example, "#,#@#" indicates a minimum of one significant digit, a maximum of two significant digits, and a grouping size of three.
  • In order to enable significant digits formatting, use a pattern containing the '@' pattern character.
  • In order to disable significant digits formatting, use a pattern that does not contain the '@' pattern character.
  • The number of significant digits has no effect on parsing.
  • Significant digits may be used together with exponential notation. Such patterns are equivalent to a normal exponential pattern with a minimum and maximum integer digit count of one, a minimum fraction digit count of the number of '@' characters in the pattern - 1, and a maximum fraction digit count of the number of '@' and '#' characters in the pattern - 1. For example, the pattern "@@###E0" is equivalent to "0.0###E0".
  • If signficant digits are in use then the integer and fraction digit counts, as set via the API, are ignored.

NEW  Padding

DecimalFormat supports padding the result of format to a specific width. Padding may be specified either through the API or through the pattern syntax. In a pattern, the pad escape character followed by a single pad character causes padding to be parsed and formatted. The pad escape character is '*' in unlocalized patterns. For example, "$*x#,##0.00" formats 123 to "$xx123.00", and 1234 to "$1,234.00".

  • When padding is in effect, the width of the positive subpattern, including prefix and suffix, determines the format width. For example, in the pattern "* #0 o''clock", the format width is 10.
  • The width is counted in 16-bit code units (Java chars).
  • Some parameters which usually do not matter have meaning when padding is used, because the pattern width is significant with padding. In the pattern "* ##,##,#,##0.##", the format width is 14. The initial characters "##,##," do not affect the grouping size or maximum integer digits, but they do affect the format width.
  • Padding may be inserted at one of four locations: before the prefix, after the prefix, before the suffix or after the suffix. If padding is specified in any other location, applyPattern(String) throws an IllegalArgumentException. If there is no prefix, before the prefix and after the prefix are equivalent, likewise for the suffix.
  • When specified in a pattern, the 16-bit char immediately following the pad escape is the pad character. This may be any character, including a special pattern character. That is, the pad escape escapes the following character. If there is no character after the pad escape, then the pattern is illegal.

Synchronization

DecimalFormat objects are not synchronized. Multiple threads should not access one formatter concurrently.

Summary

[Expand]
Inherited Constants
From class java.text.NumberFormat
Public Constructors
DecimalFormat()
Constructs a new DecimalFormat for formatting and parsing numbers for the default locale.
DecimalFormat(String pattern)
Constructs a new DecimalFormat using the specified non-localized pattern and the DecimalFormatSymbols for the default Locale.
DecimalFormat(String pattern, DecimalFormatSymbols value)
Constructs a new DecimalFormat using the specified non-localized pattern and DecimalFormatSymbols.
Public Methods
void applyLocalizedPattern(String pattern)
Changes the pattern of this decimal format to the specified pattern which uses localized pattern characters.
void applyPattern(String pattern)
Changes the pattern of this decimal format to the specified pattern which uses non-localized pattern characters.
Object clone()
Returns a new instance of DecimalFormat with the same pattern and properties as this decimal format.
boolean equals(Object object)
Compares the specified object to this decimal format and indicates if they are equal.
final StringBuffer format(Object number, StringBuffer toAppendTo, FieldPosition pos)
Formats the specified object as a string using the pattern of this decimal format and appends the string to the specified string buffer.
StringBuffer format(double value, StringBuffer buffer, FieldPosition position)
Formats the specified double value as a string using the pattern of this decimal format and appends the string to the specified string buffer.
StringBuffer format(long value, StringBuffer buffer, FieldPosition position)
Formats the specified long value as a string using the pattern of this decimal format and appends the string to the specified string buffer.
AttributedCharacterIterator formatToCharacterIterator(Object object)
Formats the specified object using the rules of this decimal format and returns an AttributedCharacterIterator with the formatted number and attributes.
Currency getCurrency()
Returns the currency used by this decimal format.
DecimalFormatSymbols getDecimalFormatSymbols()
Returns the DecimalFormatSymbols used by this decimal format.
int getGroupingSize()
Returns the number of digits grouped together by the grouping separator.
int getMultiplier()
Returns the multiplier which is applied to the number before formatting or after parsing.
String getNegativePrefix()
Returns the prefix which is formatted or parsed before a negative number.
String getNegativeSuffix()
Returns the suffix which is formatted or parsed after a negative number.
String getPositivePrefix()
Returns the prefix which is formatted or parsed before a positive number.
String getPositiveSuffix()
Returns the suffix which is formatted or parsed after a positive number.
int hashCode()
Returns an integer hash code for this object.
boolean isDecimalSeparatorAlwaysShown()
Indicates whether the decimal separator is shown when there are no fractional digits.
boolean isGroupingUsed()
Indicates whether grouping will be used in this format.
boolean isParseBigDecimal()
This value indicates whether the return object of the parse operation is of type BigDecimal.
boolean isParseIntegerOnly()
Indicates whether parsing with this decimal format will only return numbers of type java.lang.Integer.
Number parse(String string, ParsePosition position)
Parses a Long or Double from the specified string starting at the index specified by position.
void setCurrency(Currency currency)
Sets the currency used by this decimal format.
void setDecimalFormatSymbols(DecimalFormatSymbols value)
Sets the DecimalFormatSymbols used by this decimal format.
void setDecimalSeparatorAlwaysShown(boolean value)
Sets whether the decimal separator is shown when there are no fractional digits.
void setGroupingSize(int value)
Sets the number of digits grouped together by the grouping separator.
void setGroupingUsed(boolean value)
Sets whether or not grouping will be used in this format.
void setMaximumFractionDigits(int value)
Sets the maximum number of fraction digits that are printed when formatting numbers other than BigDecimal and BigInteger.
void setMaximumIntegerDigits(int value)
Sets the maximum number of integer digits that are printed when formatting numbers other than BigDecimal and BigInteger.
void setMinimumFractionDigits(int value)
Sets the minimum number of fraction digits that are printed when formatting numbers other than BigDecimal and BigInteger.
void setMinimumIntegerDigits(int value)
Sets the minimum number of integer digits that are printed when formatting numbers other than BigDecimal and BigInteger.
void setMultiplier(int value)
Sets the multiplier which is applied to the number before formatting or after parsing.
void setNegativePrefix(String value)
Sets the prefix which is formatted or parsed before a negative number.
void setNegativeSuffix(String value)
Sets the suffix which is formatted or parsed after a negative number.
void setParseBigDecimal(boolean newValue)
Sets the behaviour of the parse method.
void setParseIntegerOnly(boolean value)
Sets the flag that indicates whether numbers will be parsed as integers.
void setPositivePrefix(String value)
Sets the prefix which is formatted or parsed before a positive number.
void setPositiveSuffix(String value)
Sets the suffix which is formatted or parsed after a positive number.
String toLocalizedPattern()
Returns the pattern of this decimal format using localized pattern characters.
String toPattern()
Returns the pattern of this decimal format using non-localized pattern characters.
[Expand]
Inherited Methods
From class java.text.NumberFormat
From class java.text.Format
From class java.lang.Object

Public Constructors

public DecimalFormat ()

Constructs a new DecimalFormat for formatting and parsing numbers for the default locale.

public DecimalFormat (String pattern)

Constructs a new DecimalFormat using the specified non-localized pattern and the DecimalFormatSymbols for the default Locale.

Parameters
pattern the non-localized pattern.
Throws
IllegalArgumentException if the pattern cannot be parsed.

public DecimalFormat (String pattern, DecimalFormatSymbols value)

Constructs a new DecimalFormat using the specified non-localized pattern and DecimalFormatSymbols.

Parameters
pattern the non-localized pattern.
value the DecimalFormatSymbols.
Throws
IllegalArgumentException if the pattern cannot be parsed.

Public Methods

public void applyLocalizedPattern (String pattern)

Changes the pattern of this decimal format to the specified pattern which uses localized pattern characters.

Parameters
pattern the localized pattern.
Throws
IllegalArgumentException if the pattern cannot be parsed.

public void applyPattern (String pattern)

Changes the pattern of this decimal format to the specified pattern which uses non-localized pattern characters.

Parameters
pattern the non-localized pattern.
Throws
IllegalArgumentException if the pattern cannot be parsed.

public Object clone ()

Returns a new instance of DecimalFormat with the same pattern and properties as this decimal format.

Returns
  • a shallow copy of this decimal format.
See Also

public boolean equals (Object object)

Compares the specified object to this decimal format and indicates if they are equal. In order to be equal, object must be an instance of DecimalFormat with the same pattern and properties.

Parameters
object the object to compare with this object.
Returns
  • true if the specified object is equal to this decimal format; false otherwise.
See Also

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

Formats the specified object as a string using the pattern of this decimal format and appends the string to the specified string buffer.

If the field member of position contains a value specifying a format field, then its beginIndex and endIndex members will be updated with the position of the first occurrence of this field in the formatted text.

Parameters
number the object to format.
toAppendTo the target string buffer to append the formatted number to.
pos on input: an optional alignment field; on output: the offsets of the alignment field in the formatted text.
Returns
  • the string buffer.
Throws
IllegalArgumentException if number is not an instance of Number.
NullPointerException if toAppendTo or pos is null.

public StringBuffer format (double value, StringBuffer buffer, FieldPosition position)

Formats the specified double value as a string using the pattern of this decimal format and appends the string to the specified string buffer.

If the field member of position contains a value specifying a format field, then its beginIndex and endIndex members will be updated with the position of the first occurrence of this field in the formatted text.

Parameters
value the double to format.
buffer the target string buffer to append the formatted double value to.
position on input: an optional alignment field; on output: the offsets of the alignment field in the formatted text.
Returns
  • the string buffer.

public StringBuffer format (long value, StringBuffer buffer, FieldPosition position)

Formats the specified long value as a string using the pattern of this decimal format and appends the string to the specified string buffer.

If the field member of position contains a value specifying a format field, then its beginIndex and endIndex members will be updated with the position of the first occurrence of this field in the formatted text.

Parameters
value the long to format.
buffer the target string buffer to append the formatted long value to.
position on input: an optional alignment field; on output: the offsets of the alignment field in the formatted text.
Returns
  • the string buffer.

public AttributedCharacterIterator formatToCharacterIterator (Object object)

Formats the specified object using the rules of this decimal format and returns an AttributedCharacterIterator with the formatted number and attributes.

Parameters
object the object to format.
Returns
  • an AttributedCharacterIterator with the formatted number and attributes.
Throws
IllegalArgumentException if object cannot be formatted by this format.
NullPointerException if object is null.

public Currency getCurrency ()

Returns the currency used by this decimal format.

Returns
  • the currency used by this decimal format.
See Also

public DecimalFormatSymbols getDecimalFormatSymbols ()

Returns the DecimalFormatSymbols used by this decimal format.

Returns
  • a copy of the DecimalFormatSymbols used by this decimal format.

public int getGroupingSize ()

Returns the number of digits grouped together by the grouping separator. This only allows to get the primary grouping size. There is no API to get the secondary grouping size.

Returns
  • the number of digits grouped together.

public int getMultiplier ()

Returns the multiplier which is applied to the number before formatting or after parsing.

Returns
  • the multiplier.

public String getNegativePrefix ()

Returns the prefix which is formatted or parsed before a negative number.

Returns
  • the negative prefix.

public String getNegativeSuffix ()

Returns the suffix which is formatted or parsed after a negative number.

Returns
  • the negative suffix.

public String getPositivePrefix ()

Returns the prefix which is formatted or parsed before a positive number.

Returns
  • the positive prefix.

public String getPositiveSuffix ()

Returns the suffix which is formatted or parsed after a positive number.

Returns
  • the positive suffix.

public int hashCode ()

Returns an integer hash code for this object. By contract, any two objects for which equals(Object) returns true must return the same hash code value. This means that subclasses of Object usually override both methods or neither method.

Returns
  • this object's hash code.

public boolean isDecimalSeparatorAlwaysShown ()

Indicates whether the decimal separator is shown when there are no fractional digits.

Returns
  • true if the decimal separator should always be formatted; false otherwise.

public boolean isGroupingUsed ()

Indicates whether grouping will be used in this format.

Returns
  • true if grouping is used; false otherwise.

public boolean isParseBigDecimal ()

This value indicates whether the return object of the parse operation is of type BigDecimal. This value defaults to false.

Returns
  • true if parse always returns BigDecimals, false if the type of the result is Long or Double.

public boolean isParseIntegerOnly ()

Indicates whether parsing with this decimal format will only return numbers of type java.lang.Integer.

Returns
  • true if this DecimalFormat's parse method only returns java.lang.Integer; false otherwise.

public Number parse (String string, ParsePosition position)

Parses a Long or Double from the specified string starting at the index specified by position. If the string is successfully parsed then the index of the ParsePosition is updated to the index following the parsed text. On error, the index is unchanged and the error index of ParsePosition is set to the index where the error occurred.

Parameters
string the string to parse.
position input/output parameter, specifies the start index in string from where to start parsing. If parsing is successful, it is updated with the index following the parsed text; on error, the index is unchanged and the error index is set to the index where the error occurred.
Returns
  • a Long or Double resulting from the parse or null if there is an error. The result will be a Long if the parsed number is an integer in the range of a long, otherwise the result is a Double. If isParseBigDecimal is true then it returns the result as a BigDecimal.

public void setCurrency (Currency currency)

Sets the currency used by this decimal format. The min and max fraction digits remain the same.

Parameters
currency the currency this DecimalFormat should use.

public void setDecimalFormatSymbols (DecimalFormatSymbols value)

Sets the DecimalFormatSymbols used by this decimal format.

Parameters
value the DecimalFormatSymbols to set.

public void setDecimalSeparatorAlwaysShown (boolean value)

Sets whether the decimal separator is shown when there are no fractional digits.

Parameters
value true if the decimal separator should always be formatted; false otherwise.

public void setGroupingSize (int value)

Sets the number of digits grouped together by the grouping separator. This only allows to set the primary grouping size; the secondary grouping size can only be set with a pattern.

Parameters
value the number of digits grouped together.

public void setGroupingUsed (boolean value)

Sets whether or not grouping will be used in this format. Grouping affects both parsing and formatting.

Parameters
value true if grouping is used; false otherwise.

public void setMaximumFractionDigits (int value)

Sets the maximum number of fraction digits that are printed when formatting numbers other than BigDecimal and BigInteger. If the maximum is less than the number of fraction digits, the least significant digits are truncated. If the value passed is bigger than 340 then it is replaced by 340. If the value passed is negative then it is replaced by 0.

Parameters
value the maximum number of fraction digits.

public void setMaximumIntegerDigits (int value)

Sets the maximum number of integer digits that are printed when formatting numbers other than BigDecimal and BigInteger. If the maximum is less than the number of integer digits, the most significant digits are truncated. If the value passed is bigger than 309 then it is replaced by 309. If the value passed is negative then it is replaced by 0.

Parameters
value the maximum number of integer digits.

public void setMinimumFractionDigits (int value)

Sets the minimum number of fraction digits that are printed when formatting numbers other than BigDecimal and BigInteger. If the value passed is bigger than 340 then it is replaced by 340. If the value passed is negative then it is replaced by 0.

Parameters
value the minimum number of fraction digits.

public void setMinimumIntegerDigits (int value)

Sets the minimum number of integer digits that are printed when formatting numbers other than BigDecimal and BigInteger. If the value passed is bigger than 309 then it is replaced by 309. If the value passed is negative then it is replaced by 0.

Parameters
value the minimum number of integer digits.

public void setMultiplier (int value)

Sets the multiplier which is applied to the number before formatting or after parsing.

Parameters
value the multiplier.

public void setNegativePrefix (String value)

Sets the prefix which is formatted or parsed before a negative number.

Parameters
value the negative prefix.

public void setNegativeSuffix (String value)

Sets the suffix which is formatted or parsed after a negative number.

Parameters
value the negative suffix.

public void setParseBigDecimal (boolean newValue)

Sets the behaviour of the parse method. If set to true then all the returned objects will be of type BigDecimal.

Parameters
newValue true if all the returned objects should be of type BigDecimal; false otherwise.

public void setParseIntegerOnly (boolean value)

Sets the flag that indicates whether numbers will be parsed as integers. When this decimal format is used for parsing and this value is set to true, then the resulting numbers will be of type java.lang.Integer. Special cases are NaN, positive and negative infinity, which are still returned as java.lang.Double.

Parameters
value true that the resulting numbers of parse operations will be of type java.lang.Integer except for the special cases described above.

public void setPositivePrefix (String value)

Sets the prefix which is formatted or parsed before a positive number.

Parameters
value the positive prefix.

public void setPositiveSuffix (String value)

Sets the suffix which is formatted or parsed after a positive number.

Parameters
value the positive suffix.

public String toLocalizedPattern ()

Returns the pattern of this decimal format using localized pattern characters.

Returns
  • the localized pattern.

public String toPattern ()

Returns the pattern of this decimal format using non-localized pattern characters.

Returns
  • the non-localized pattern.