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29.9 java.text.DecimalFormat (JDK 1.1)

This is the concrete Format class used by NumberFormat for all locales that use base 10 numbers. Most applications do not need to use this class directly--they can use the static methods of NumberFormat to obtain a default NumberFormat object for a desired locale, and may then perform minor locale-independent customizations on that object.

Applications that require highly-customized number formatting and parsing may create custom DecimalFormat objects by passing a suitable pattern to the DecimalFormat() constructor method. The applyPattern() method can be used to change this pattern. A pattern consists of a string of characters from the following table. For example: "$#,##0.00;($#,##0.00)".

Character Meaning
# A digit; zeros show as absent
0 A digit; zeros show as 0
. The locale-specific decimal separator
, The locale-specific grouping separator
- The locale-specific negative prefix
% Show value as a percentage
;

Separates positive number format (on left) from optional negative number format (on right)

'

Quote a reserved character, so it appears literally in the output

other Appears literally in output

A DecimalFormatSymbols object may be optionally specified when creating a DecimalFormat object. If one is not specified, a DecimalFormatSymbols object suitable for the default locale is used.

public class DecimalFormat extends NumberFormat {
    // Public Constructors
            public DecimalFormat();
            public DecimalFormat(String pattern);
            public DecimalFormat(String pattern, DecimalFormatSymbols symbols);
    // Public Instance Methods
            public void applyLocalizedPattern(String pattern);
            public void applyPattern(String pattern);
            public Object clone();  // Overrides NumberFormat
            public boolean equals(Object obj);  // Overrides NumberFormat
            public StringBuffer format(double number, StringBuffer result, FieldPosition fieldPosition);  // Defines NumberFormat
            public StringBuffer format(long number, StringBuffer result, FieldPosition fieldPosition);  // Defines NumberFormat
            public DecimalFormatSymbols getDecimalFormatSymbols();
            public int getGroupingSize();
            public int getMultiplier();
            public String getNegativePrefix();
            public String getNegativeSuffix();
            public String getPositivePrefix();
            public String getPositiveSuffix();
            public int hashCode();  // Overrides NumberFormat
            public boolean isDecimalSeparatorAlwaysShown();
            public Number parse(String text, ParsePosition status);  // Defines NumberFormat
            public void setDecimalFormatSymbols(DecimalFormatSymbols newSymbols);
            public void setDecimalSeparatorAlwaysShown(boolean newValue);
            public void setGroupingSize(int newValue);
            public void setMultiplier(int newValue);
            public void setNegativePrefix(String newValue);
            public void setNegativeSuffix(String newValue);
            public void setPositivePrefix(String newValue);
            public void setPositiveSuffix(String newValue);
            public String toLocalizedPattern();
            public String toPattern();
}

Hierarchy:

Object->Format(Serializable, Cloneable)->NumberFormat(Cloneable)->DecimalFormat


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