Class DecimalFormat

java.lang.Object
java.text.Format
java.text.NumberFormat
java.text.DecimalFormat
All Implemented Interfaces:
Serializable, Cloneable
public class DecimalFormat extends NumberFormat
DecimalFormat is a concrete subclass of NumberFormat that formats decimal numbers in a localized manner. It has a variety of features designed to make it possible to parse and format numbers in any locale, including support for Western, Arabic, and Indic digits. It also supports different kinds of numbers, including integers (123), fixed-point numbers (123.4), scientific notation (1.23E4), percentages (12%), and currency amounts ($123).

Getting a DecimalFormat

To obtain a standard decimal format for a specific locale, including the default locale, it is recommended to call one of the NumberFormat factory methods, such as NumberFormat.getInstance(). These factory methods may not always return a DecimalFormat depending on the locale-service provider implementation installed. Thus, to use an instance method defined by DecimalFormat, the NumberFormat returned by the factory method should be type checked before converted to DecimalFormat. If the installed locale-sensitive service implementation does not support the given Locale, the parent locale chain will be looked up, and a Locale used that is supported.

If the factory methods are not desired, use one of the constructors such as DecimalFormat(String pattern). See the Pattern section for more information on the pattern parameter.

Using DecimalFormat

The following is an example of formatting and parsing, 
NumberFormat nFmt = NumberFormat.getCurrencyInstance(Locale.US);
if (nFmt instanceof DecimalFormat dFmt) {
    // pattern match to DecimalFormat to use setPositiveSuffix(String)
    dFmt.setPositiveSuffix(" dollars");
    dFmt.format(100000); // returns "$100,000.00 dollars"
    dFmt.parse("$100,000.00 dollars"); // returns 100000
}

Formatting and Parsing

Rounding

When formatting, DecimalFormat can adjust its rounding using setRoundingMode(RoundingMode). By default, it uses RoundingMode.HALF_EVEN.

Digits

When formatting, DecimalFormat uses the ten consecutive characters starting with the localized zero digit defined in the DecimalFormatSymbols object as digits.

When parsing, these digits as well as all Unicode decimal digits, as defined by Character.digit, are recognized.

Integer and Fraction Digit Limits

The integer and fraction digit limits are set by either applying a pattern or using one of the appropriate DecimalFormat setter methods, for example, setMinimumFractionDigits(int). These limits have no impact on parsing behavior.

Special Values

  • Not a Number (NaN) is formatted as a string, which is typically given as "NaN". This string is determined by DecimalFormatSymbols.getNaN(). This is the only value for which the prefixes and suffixes are not attached.

  • Infinity is formatted as a string, which is typically given as "∞" (U+221E), with the positive or negative prefixes and suffixes attached. This string is determined by DecimalFormatSymbols.getInfinity().

  • Negative zero ("-0") parses to

    • BigDecimal(0) if isParseBigDecimal() is true
    • Long(0) if isParseBigDecimal() is false and isParseIntegerOnly() is true
    • Double(-0.0) if both isParseBigDecimal() and isParseIntegerOnly() are false

Synchronization

Decimal formats are generally not synchronized. It is recommended to create separate format instances for each thread. If multiple threads access a format concurrently, it must be synchronized externally.

DecimalFormat Pattern

A DecimalFormat comprises a pattern and a set of symbols. The pattern may be set directly using applyPattern(), or indirectly using the various API methods. The symbols are stored in a DecimalFormatSymbols object. When using the NumberFormat factory methods, the pattern and symbols are created from the locale-sensitive service implementation installed.

DecimalFormat patterns have the following syntax: 

Pattern:
        PositivePattern
        PositivePattern ; NegativePattern
PositivePattern:
        Prefixopt Number Suffixopt
NegativePattern:
        Prefixopt Number Suffixopt
Prefix:
        Any characters except the special pattern characters
Suffix:
        Any characters except the special pattern characters
Number:
        Integer Exponentopt
        Integer . Fraction Exponentopt
Integer:
        MinimumInteger
        #
        # Integer
        # , Integer
MinimumInteger:
        0
        0 MinimumInteger
        0 , MinimumInteger
Fraction:
        MinimumFractionopt OptionalFractionopt
MinimumFraction:
        0 MinimumFractionopt
OptionalFraction:
        # OptionalFractionopt
Exponent:
        E MinimumExponent
MinimumExponent:
        0 MinimumExponentopt

Special Pattern Characters

The special characters in the table below are interpreted syntactically when used in the DecimalFormat pattern. They must be quoted, unless noted otherwise, if they are to appear in the prefix or suffix as literals.

The characters in the Symbol column are used in non-localized patterns. The corresponding characters in the Localized Symbol column are used in localized patterns, with the characters in Symbol losing their syntactical meaning. Two exceptions are the currency sign (U+00A4) and quote (U+0027), which are not localized.

Non-localized patterns should be used when calling applyPattern(String). Localized patterns should be used when calling applyLocalizedPattern(String).

Chart showing symbol, location, localized, and meaning.
Symbol Localized Symbol Location Meaning
0 DecimalFormatSymbols.getZeroDigit() Number Digit
# DecimalFormatSymbols.getDigit() Number Digit, zero shows as absent
. DecimalFormatSymbols.getDecimalSeparator() Number Decimal separator or monetary decimal separator
- (U+002D) DecimalFormatSymbols.getMinusSign() Number Minus sign
, DecimalFormatSymbols.getGroupingSeparator() Number Grouping separator or monetary grouping separator
E DecimalFormatSymbols.getExponentSeparator() Number Separates mantissa and exponent in scientific notation. This value is case sensistive. Need not be quoted in prefix or suffix.
; DecimalFormatSymbols.getPatternSeparator() Subpattern boundary Separates positive and negative subpatterns
% DecimalFormatSymbols.getPercent() Prefix or suffix Multiply by 100 and show as percentage
‰ (U+2030) DecimalFormatSymbols.getPerMill() Prefix or suffix Multiply by 1000 and show as per mille value
¤ (U+00A4) n/a (not localized) Prefix or suffix Currency sign, replaced by currency symbol. If doubled, replaced by international currency symbol. If present in a pattern, the monetary decimal/grouping separators are used instead of the decimal/grouping separators.
' (U+0027) n/a (not localized) Prefix or suffix 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".

Maximum Digits Derivation

For any given DecimalFormat pattern, if the pattern is not in scientific notation, the maximum number of integer digits will not be derived from the pattern, and instead set to Integer.MAX_VALUE. Otherwise, if the pattern is in scientific notation, the maximum number of integer digits will be derived from the pattern. This derivation is detailed in the Scientific Notation section. setMaximumIntegerDigits(int) can be used to manually adjust the maximum integer digits.

Negative Subpatterns

A DecimalFormat pattern contains a positive and negative subpattern, for example, "#,##0.00;(#,##0.00)". Each subpattern has a prefix, numeric part, and suffix. The negative subpattern is optional; if absent, then the positive subpattern prefixed with the minus sign '-' (U+002D HYPHEN-MINUS) is used as the negative 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 all the same as the positive pattern. That means that "#,##0.0#;(#)" produces precisely the same behavior as "#,##0.0#;(#,##0.0#)". In lenient parsing mode, loose matching of the minus sign pattern is enabled, following the LDML’s loose matching specification.

The prefixes, suffixes, and various symbols used for infinity, digits, grouping 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 DecimalFormat.parse() to be able to distinguish positive from negative values. (If they are identical, then DecimalFormat will behave as if no negative subpattern was specified.) Another example is that the decimal separator and grouping separator should be distinct characters, or parsing will be impossible.

Grouping Separator

The grouping separator is commonly used for thousands, but in some locales it separates ten-thousands. The grouping size is a constant number of digits between the grouping characters, such as 3 for 100,000,000 or 4 for 1,0000,0000. If you supply a pattern with multiple grouping characters, the interval between the last one and the end of the integer is the one that is used. For example, "#,##,###,####" == "######,####" == "##,####,####".

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 10^3. The mantissa is often in the range 1.0 ≤ x < 10.0, but it need not be. DecimalFormat can be instructed to format and parse scientific notation only via a pattern; there is currently no factory method that creates a scientific notation format. In a pattern, the exponent character immediately followed by one or more digit characters indicates scientific notation. Example: "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".
  • The maximum integer digits is the sum of '0's and '#'s prior to the decimal point. The minimum integer digits is the sum of the '0's prior to the decimal point. The maximum fraction and minimum fraction digits follow the same rules, but apply to the digits after the decimal point but before the exponent. For example, the following pattern: "#00.0####E0" would have a minimum number of integer digits = 2("00") and a maximum number of integer digits = 3("#00"). It would have a minimum number of fraction digits = 1("0") and a maximum number of fraction digits= 5("0####").
  • The minimum and maximum number of integer digits are interpreted together:
    • If the maximum number of integer digits is greater than their minimum number and greater than 1, it forces the exponent to be a multiple of the maximum number of integer digits, and the minimum number of integer digits to be interpreted as 1. The most common use of this is to generate engineering notation, in which the exponent is a multiple of three, e.g., "##0.#####E0". Using this pattern, the number 12345 formats to "12.345E3", and 123456 formats to "123.456E3".
    • Otherwise, the minimum number of integer digits is achieved by adjusting the exponent. Example: 0.00123 formatted with "00.###E0" yields "12.3E-4".
  • For a given number, the amount of significant digits in the mantissa can be calculated as such 
    Mantissa Digits:
        min(max(Minimum Pattern Digits, Original Number Digits), Maximum Pattern Digits)
Minimum pattern Digits:
        Minimum Integer Digits + Minimum Fraction Digits
Maximum pattern Digits:
        Maximum Integer Digits + Maximum Fraction Digits
Original Number Digits:
        The amount of significant digits in the number to be formatted
    This means that generally, a mantissa will have up to the combined maximum integer and fraction digits, if the original number itself has enough significant digits. However, if there are more minimum pattern digits than significant digits in the original number, the mantissa will have significant digits that equals the combined minimum integer and fraction digits. The number of significant digits does not affect parsing.

    It should be noted, that the integer portion of the mantissa will give any excess digits to the fraction portion, whether it be for precision or for satisfying the total amount of combined minimum digits.

    This behavior can be observed in the following example, 

        DecimalFormat df = new DecimalFormat("#000.000##E0");
    df.format(12); // returns "12.0000E0"
    df.format(123456789) // returns "1.23456789E8"
  • Exponential patterns may not contain grouping separators.
Implementation Requirements:
When formatting a Number other than BigInteger and BigDecimal, 309 is used as the upper limit for integer digits, and 340 as the upper limit for fraction digits. This occurs, even if one of the DecimalFormat getter methods, for example, getMinimumFractionDigits() returns a numerically greater value.
Since:
1.1
External Specifications
See Also:

  • Constructor Details

  • Method Details

    • format

      public final StringBuffer format(Object number, StringBuffer toAppendTo, FieldPosition pos)
      Formats a number and appends the resulting text to the given string buffer. The number can be of any subclass of Number.
      Overrides:
      format in class NumberFormat
      Implementation Requirements:
      This implementation uses the maximum precision permitted.
      Parameters:
      number - the number to format
      toAppendTo - the StringBuffer to which the formatted text is to be appended
      pos - keeps track on the position of the field within the returned string. For example, for formatting a number 1234567.89 in Locale.US locale, if the given fieldPosition is NumberFormat.INTEGER_FIELD, the begin index and end index of fieldPosition will be set to 0 and 9, respectively for the output string 1,234,567.89.
      Returns:
      the value passed in as toAppendTo
      Throws:
      IllegalArgumentException - if number is null or not an instance of Number.
      NullPointerException - if toAppendTo or pos is null
      ArithmeticException - if rounding is needed with rounding mode being set to RoundingMode.UNNECESSARY
      See Also:

    • format

      public StringBuffer format(double number, StringBuffer result, FieldPosition fieldPosition)
      Formats a double to produce a string.
      Specified by:
      format in class NumberFormat
      Parameters:
      number - The double to format
      result - where the text is to be appended
      fieldPosition - keeps track on the position of the field within the returned string. For example, for formatting a number 1234567.89 in Locale.US locale, if the given fieldPosition is NumberFormat.INTEGER_FIELD, the begin index and end index of fieldPosition will be set to 0 and 9, respectively for the output string 1,234,567.89.
      Returns:
      The formatted number string
      Throws:
      NullPointerException - if result or fieldPosition is null
      ArithmeticException - if rounding is needed with rounding mode being set to RoundingMode.UNNECESSARY
      See Also:

    • format

      public StringBuffer format(long number, StringBuffer result, FieldPosition fieldPosition)
      Format a long to produce a string.
      Specified by:
      format in class NumberFormat
      Parameters:
      number - The long to format
      result - where the text is to be appended
      fieldPosition - keeps track on the position of the field within the returned string. For example, for formatting a number 123456789 in Locale.US locale, if the given fieldPosition is NumberFormat.INTEGER_FIELD, the begin index and end index of fieldPosition will be set to 0 and 11, respectively for the output string 123,456,789.
      Returns:
      The formatted number string
      Throws:
      NullPointerException - if result or fieldPosition is null
      ArithmeticException - if rounding is needed with rounding mode being set to RoundingMode.UNNECESSARY
      See Also:

    • formatToCharacterIterator

      public AttributedCharacterIterator formatToCharacterIterator(Object obj)
      Formats an Object producing an AttributedCharacterIterator. You can use the returned AttributedCharacterIterator to build the resulting String, as well as to determine information about the resulting String.

      Each attribute key of the AttributedCharacterIterator will be of type NumberFormat.Field, with the attribute value being the same as the attribute key.

      Overrides:
      formatToCharacterIterator in class Format
      Parameters:
      obj - The object to format
      Returns:
      AttributedCharacterIterator describing the formatted value.
      Throws:
      NullPointerException - if obj is null.
      IllegalArgumentException - when the Format cannot format the given object.
      ArithmeticException - if rounding is needed with rounding mode being set to RoundingMode.UNNECESSARY
      Since:
      1.4

    • parse

      public Number parse(String text, ParsePosition pos)
      Parses text from the beginning of the given string to produce a Number.

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

      This method will return a Long if possible (e.g., within the range [Long.MIN_VALUE, Long.MAX_VALUE] and with no decimals), otherwise a Double.

      Parsing can be done in either a strict or lenient manner, by default it is lenient.

      Parsing fails when lenient, if the prefix and/or suffix are non-empty and cannot be found due to parsing ending early, or the first character after the prefix cannot be parsed.

      Parsing fails when strict, if in text,

      • The prefix is not found. For example, a Locale.US currency format prefix: "$"
      • The suffix is not found. For example, a Locale.US percent format suffix: "%"
      • NumberFormat.isGroupingUsed() returns true, and getGroupingSize() is not adhered to
      • NumberFormat.isGroupingUsed() returns false, and the grouping symbol is found
      • NumberFormat.isGroupingUsed() returns true and the grouping symbol occurs after the decimal separator
      • Any other characters are found, that are not the expected symbols, and are not digits that occur within the numerical portion

      When lenient, the minus sign in the negative subpatterns is loosely matched against lenient minus sign characters.

      The subclass returned depends on the value of isParseBigDecimal() as well as on the string being parsed.

      • If isParseBigDecimal() is false (the default), most integer values are returned as Long objects, no matter how they are written: "17" and "17.000" both parse to Long(17). Values that cannot fit into a Long are returned as Doubles. This includes values with a fractional part, infinite values, NaN, and the value -0.0. DecimalFormat does not decide whether to return a Double or a Long based on the presence of a decimal separator in the source string. Doing so would prevent integers that overflow the mantissa of a double, such as "-9,223,372,036,854,775,808.00", from being parsed accurately.

        Callers may use the Number methods doubleValue, longValue, etc., to obtain the type they want.

      • If isParseBigDecimal() is true, values are returned as BigDecimal objects. The values are the ones constructed by BigDecimal(String) for corresponding strings in locale-independent format. The special cases negative and positive infinity and NaN are returned as Double instances holding the values of the corresponding Double constants.

      DecimalFormat parses all Unicode characters that represent decimal digits, as defined by Character.digit(). In addition, DecimalFormat also recognizes as digits the ten consecutive characters starting with the localized zero digit defined in the DecimalFormatSymbols object.

      Specified by:
      parse in class NumberFormat
      Parameters:
      text - the string to be parsed
      pos - A ParsePosition object with index and error index information as described above.
      Returns:
      the parsed value, or null if the parse fails
      Throws:
      NullPointerException - if text or pos is null.
      See Also:

    • getDecimalFormatSymbols

      public DecimalFormatSymbols getDecimalFormatSymbols()
      Returns a copy of the decimal format symbols, which is generally not changed by the programmer or user.
      Returns:
      a copy of the desired DecimalFormatSymbols
      See Also:

    • setDecimalFormatSymbols

      public void setDecimalFormatSymbols(DecimalFormatSymbols newSymbols)
      Sets the decimal format symbols, which is generally not changed by the programmer or user.
      Parameters:
      newSymbols - desired DecimalFormatSymbols
      See Also:

    • getPositivePrefix

      public String getPositivePrefix()
      Get the positive prefix.

      Examples: +123, $123, sFr123

      Returns:
      the positive prefix

    • setPositivePrefix

      public void setPositivePrefix(String newValue)
      Set the positive prefix.

      Examples: +123, $123, sFr123

      Parameters:
      newValue - the new positive prefix. Non-null.
      Throws:
      NullPointerException - if newValue is null

    • getNegativePrefix

      public String getNegativePrefix()
      Get the negative prefix.

      Examples: -123, ($123) (with negative suffix), sFr-123

      Returns:
      the negative prefix

    • setNegativePrefix

      public void setNegativePrefix(String newValue)
      Set the negative prefix.

      Examples: -123, ($123) (with negative suffix), sFr-123

      Parameters:
      newValue - the new negative prefix. Non-null.
      Throws:
      NullPointerException - if newValue is null

    • getPositiveSuffix

      public String getPositiveSuffix()
      Get the positive suffix.

      Example: 123%

      Returns:
      the positive suffix

    • setPositiveSuffix

      public void setPositiveSuffix(String newValue)
      Set the positive suffix.

      Example: 123%

      Parameters:
      newValue - the new positive suffix. Non-null.
      Throws:
      NullPointerException - if newValue is null

    • getNegativeSuffix

      public String getNegativeSuffix()
      Get the negative suffix.

      Examples: -123%, ($123) (with positive suffixes)

      Returns:
      the negative suffix

    • setNegativeSuffix

      public void setNegativeSuffix(String newValue)
      Set the negative suffix.

      Examples: 123%

      Parameters:
      newValue - the new negative suffix. Non-null.
      Throws:
      NullPointerException - if newValue is null

    • getMultiplier

      public int getMultiplier()
      Gets the multiplier for use in percent, per mille, and similar formats.
      Returns:
      the multiplier
      See Also:

    • setMultiplier

      public void setMultiplier(int newValue)
      Sets the multiplier for use in percent, per mille, and similar formats. For a percent format, set the multiplier to 100 and the suffixes to have '%' (for Arabic, use the Arabic percent sign). For a per mille format, set the multiplier to 1000 and the suffixes to have 'U+2030'.

      Example: with multiplier 100, 1.23 is formatted as "123", and "123" is parsed into 1.23. If isParseIntegerOnly() returns true, "123" is parsed into 1.

      Parameters:
      newValue - the new multiplier
      See Also:

    • getGroupingSize

      public int getGroupingSize()
      Return the grouping size. Grouping size is the number of digits between grouping separators in the integer portion of a number. For example, in the number "123,456.78", the grouping size is 3. Grouping size of zero designates that grouping is not used, which provides the same formatting as if calling setGroupingUsed(false).
      Returns:
      the grouping size
      See Also:

    • setGroupingSize

      public void setGroupingSize(int newValue)
      Set the grouping size. Grouping size is the number of digits between grouping separators in the integer portion of a number. For example, in the number "123,456.78", the grouping size is 3. Grouping size of zero designates that grouping is not used, which provides the same formatting as if calling setGroupingUsed(false).

      The value passed in is converted to a byte, which may lose information. Values that are negative or greater than Byte.MAX_VALUE, will throw an IllegalArgumentException.

      Parameters:
      newValue - the new grouping size
      Throws:
      IllegalArgumentException - if newValue is negative or greater than Byte.MAX_VALUE
      See Also:

    • isDecimalSeparatorAlwaysShown

      public boolean isDecimalSeparatorAlwaysShown()
      Allows you to get the behavior of the decimal separator with integers. (The decimal separator will always appear with decimals.)

      Example: Decimal ON: 12345 → 12345.; OFF: 12345 → 12345

      Returns:
      true if the decimal separator is always shown; false otherwise

    • setDecimalSeparatorAlwaysShown

      public void setDecimalSeparatorAlwaysShown(boolean newValue)
      Allows you to set the behavior of the decimal separator with integers. (The decimal separator will always appear with decimals.)

      Example: Decimal ON: 12345 → 12345.; OFF: 12345 → 12345

      Parameters:
      newValue - true if the decimal separator is always shown; false otherwise

    • isStrict

      public boolean isStrict()
      Returns true if this format will parse numbers strictly; false otherwise.
      Overrides:
      isStrict in class NumberFormat
      Returns:
      true if this format will parse numbers strictly; false otherwise
      Since:
      23
      See Also:

    • setStrict

      public void setStrict(boolean strict)
      Change the leniency value for parsing. Parsing can either be strict or lenient, by default it is lenient.
      Overrides:
      setStrict in class NumberFormat
      Parameters:
      strict - true if parsing should be done strictly; false otherwise
      Since:
      23
      See Also:

    • isParseBigDecimal

      public boolean isParseBigDecimal()
      Returns whether the parse(java.lang.String, java.text.ParsePosition) method returns BigDecimal. The default value is false.
      Returns:
      true if the parse method returns BigDecimal; false otherwise
      Since:
      1.5
      See Also:

    • setParseBigDecimal

      public void setParseBigDecimal(boolean newValue)
      Sets whether the parse(java.lang.String, java.text.ParsePosition) method returns BigDecimal.
      Parameters:
      newValue - true if the parse method returns BigDecimal; false otherwise
      Since:
      1.5
      See Also:

    • clone

      public Object clone()
      Standard override; no change in semantics.
      Overrides:
      clone in class NumberFormat
      Returns:
      a clone of this instance.
      See Also:

    • equals

      public boolean equals(Object obj)
      Compares the specified object with this DecimalFormat for equality. Returns true if the object is also a DecimalFormat and the two formats would format any value the same.
      Overrides:
      equals in class NumberFormat
      Implementation Requirements:
      This method performs an equality check with a notion of class identity based on getClass(), rather than instanceof. Therefore, in the equals methods in subclasses, no instance of this class should compare as equal to an instance of a subclass.
      Parameters:
      obj - object to be compared for equality
      Returns:
      true if the specified object is equal to this DecimalFormat
      See Also:

    • hashCode

      public int hashCode()
      Returns the hash code for this DecimalFormat.
      Overrides:
      hashCode in class NumberFormat
      Implementation Requirements:
      This method calculates the hash code value using the values returned from getPositivePrefix() and NumberFormat.hashCode().
      Returns:
      the hash code for this DecimalFormat
      See Also:

    • toString

      public String toString()
      Returns a string identifying this DecimalFormat, for debugging.
      Overrides:
      toString in class Object
      Returns:
      a string identifying this DecimalFormat, for debugging

    • toPattern

      public String toPattern()
      Synthesizes a pattern string that represents the current state of this Format object.
      Returns:
      a pattern string
      See Also:

    • toLocalizedPattern

      public String toLocalizedPattern()
      Synthesizes a localized pattern string that represents the current state of this Format object.
      Returns:
      a localized pattern string
      See Also:

    • applyPattern

      public void applyPattern(String pattern)
      Apply the given pattern to this Format object. A pattern is a short-hand specification for the various formatting properties. These properties can also be changed individually through the various setter methods.

      The number of maximum integer digits is usually not derived from the pattern. See the note in the Patterns section for more detail. For negative numbers, use a second pattern, separated by a semicolon

      Example "#,#00.0#" → 1,234.56

      This means a minimum of 2 integer digits, 1 fraction digit, and a maximum of 2 fraction digits.

      Example: "#,#00.0#;(#,#00.0#)" for negatives in parentheses.

      In negative patterns, the minimum and maximum counts are ignored; these are presumed to be set in the positive pattern.

      Parameters:
      pattern - a new pattern
      Throws:
      NullPointerException - if pattern is null
      IllegalArgumentException - if the given pattern is invalid.

    • applyLocalizedPattern

      public void applyLocalizedPattern(String pattern)
      Apply the given pattern to this Format object. The pattern is assumed to be in a localized notation. A pattern is a short-hand specification for the various formatting properties. These properties can also be changed individually through the various setter methods.

      The number of maximum integer digits is usually not derived from the pattern. See the note in the Patterns section for more detail. For negative numbers, use a second pattern, separated by a semicolon

      Example "#,#00.0#" → 1,234.56

      This means a minimum of 2 integer digits, 1 fraction digit, and a maximum of 2 fraction digits.

      Example: "#,#00.0#;(#,#00.0#)" for negatives in parentheses.

      In negative patterns, the minimum and maximum counts are ignored; these are presumed to be set in the positive pattern.

      Parameters:
      pattern - a new pattern
      Throws:
      NullPointerException - if pattern is null
      IllegalArgumentException - if the given pattern is invalid.

    • setMaximumIntegerDigits

      public void setMaximumIntegerDigits(int newValue)
      Sets the maximum number of digits allowed in the integer portion of a number during formatting. 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. Negative input values are replaced with 0.
      Overrides:
      setMaximumIntegerDigits in class NumberFormat
      Parameters:
      newValue - the maximum number of integer digits to be shown.
      See Also:

    • setMinimumIntegerDigits

      public void setMinimumIntegerDigits(int newValue)
      Sets the minimum number of digits allowed in the integer portion of a number during formatting. 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. Negative input values are replaced with 0.
      Overrides:
      setMinimumIntegerDigits in class NumberFormat
      Parameters:
      newValue - the minimum number of integer digits to be shown.
      See Also:

    • setMaximumFractionDigits

      public void setMaximumFractionDigits(int newValue)
      Sets the maximum number of digits allowed in the fraction portion of a number during formatting. 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. Negative input values are replaced with 0.
      Overrides:
      setMaximumFractionDigits in class NumberFormat
      Parameters:
      newValue - the maximum number of fraction digits to be shown.
      See Also:

    • setMinimumFractionDigits

      public void setMinimumFractionDigits(int newValue)
      Sets the minimum number of digits allowed in the fraction portion of a number during formatting. minimumFractionDigits must be ≤ maximumFractionDigits. If the new value for minimumFractionDigits exceeds the current value of maximumFractionDigits, then maximumFractionDigits will also be set to the new value. Negative input values are replaced with 0.
      Overrides:
      setMinimumFractionDigits in class NumberFormat
      Parameters:
      newValue - the minimum number of fraction digits to be shown.
      See Also:

    • getMaximumIntegerDigits

      public int getMaximumIntegerDigits()
      Returns the maximum number of digits allowed in the integer portion of a number during formatting.

      Unlike the other digit limits, maximumIntegerDigits is not updated by DecimalFormats created or updated with a string pattern.

      Overrides:
      getMaximumIntegerDigits in class NumberFormat
      Returns:
      the maximum number of digits
      See Also:

    • getMinimumIntegerDigits

      public int getMinimumIntegerDigits()
      Returns the minimum number of digits allowed in the integer portion of a number during formatting.
      Overrides:
      getMinimumIntegerDigits in class NumberFormat
      Returns:
      the minimum number of digits
      See Also:

    • getMaximumFractionDigits

      public int getMaximumFractionDigits()
      Returns the maximum number of digits allowed in the fraction portion of a number during formatting.
      Overrides:
      getMaximumFractionDigits in class NumberFormat
      Returns:
      the maximum number of digits.
      See Also:

    • getMinimumFractionDigits

      public int getMinimumFractionDigits()
      Returns the minimum number of digits allowed in the fraction portion of a number during formatting.
      Overrides:
      getMinimumFractionDigits in class NumberFormat
      Returns:
      the minimum number of digits
      See Also:

    • getCurrency

      public Currency getCurrency()
      Gets the currency used by this decimal format when formatting currency values. The currency is obtained by calling DecimalFormatSymbols.getCurrency on this number format's symbols.
      Overrides:
      getCurrency in class NumberFormat
      Returns:
      the currency used by this decimal format, or null
      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 currency is set by calling DecimalFormatSymbols.setCurrency on this number format's symbols.
      Overrides:
      setCurrency in class NumberFormat
      Parameters:
      currency - the new currency to be used by this decimal format
      Throws:
      NullPointerException - if currency is null
      Since:
      1.4

    • getRoundingMode

      public RoundingMode getRoundingMode()
      Gets the RoundingMode used in this DecimalFormat.
      Overrides:
      getRoundingMode in class NumberFormat
      Returns:
      The RoundingMode used for this DecimalFormat.
      Since:
      1.6
      See Also:

    • setRoundingMode

      public void setRoundingMode(RoundingMode roundingMode)
      Sets the RoundingMode used in this DecimalFormat.
      Overrides:
      setRoundingMode in class NumberFormat
      Parameters:
      roundingMode - The RoundingMode to be used
      Throws:
      NullPointerException - if roundingMode is null.
      Since:
      1.6
      See Also: