java.lang.Object | |
↳ | java.text.Format |
Known Direct Subclasses |
Known Indirect Subclasses |
The base class for all formats.
This is an abstract base class which specifies the protocol for classes which
convert other objects or values, such as numeric values and dates, and their
string representations. In some cases these representations may be localized
or contain localized characters or strings. For example, a numeric formatter
such as DecimalFormat
may convert a numeric value such as 12345 to
the string "$12,345". It may also parse the string back into a numeric value.
A date and time formatter like SimpleDateFormat
may represent a
specific date, encoded numerically, as a string such as "Wednesday, February
26, 1997 AD".
Many of the concrete subclasses of Format
employ the notion of a
pattern. A pattern is a string representation of the rules which govern the
conversion between values and strings. For example, a DecimalFormat
object may be associated with the pattern "$#,##0.00;($#,##0.00)", which is a
common US English format for currency values, yielding strings such as
"$1,234.45" for 1234.45, and "($987.65)" for -987.6543. The specific syntax
of a pattern is defined by each subclass. Even though many subclasses use
patterns, the notion of a pattern is not inherent to Format
classes
in general, and is not part of the explicit base class protocol.
Two complex formatting classes are worth mentioning: MessageFormat
and ChoiceFormat
. ChoiceFormat
is a subclass of
NumberFormat
which allows the user to format different number ranges
as strings. For instance, 0 may be represented as "no files", 1 as "one
file", and any number greater than 1 as "many files". MessageFormat
is a formatter which utilizes other Format
objects to format a string
containing multiple values. For instance, a MessageFormat
object
might produce the string "There are no files on the disk MyDisk on February
27, 1997." given the arguments 0, "MyDisk", and the date value of 2/27/97.
See the ChoiceFormat
and MessageFormat
descriptions for
further information.
Nested Classes | |||||||||||
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Format.Field | Inner class used to represent Format attributes in the
AttributedCharacterIterator that the
formatToCharacterIterator() method returns in Format
subclasses. |
Protected Constructors | |||||||||||
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Used by subclasses.
|
Public Methods | |||||||||||
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Returns a copy of this
Format instance. | |||||||||||
Formats the specified object using the rules of this format.
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Appends the specified object to the specified string buffer using the
rules of this format.
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Formats the specified object using the rules of this format and returns
an
AttributedCharacterIterator with the formatted string and no
attributes. | |||||||||||
Parses the specified string using the rules of this format.
| |||||||||||
Parses the specified string starting at the index specified by
position . |
[Expand]
Inherited Methods | |||||||||||
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From class
java.lang.Object
|
Formats the specified object using the rules of this format.
object | the object to format. |
---|
IllegalArgumentException | if the object cannot be formatted by this format. |
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Appends the specified object to the specified string buffer using the rules of this format.
field
is an input/output parameter. If its field
member contains an enum value specifying a field on input, then its
beginIndex
and endIndex
members will be updated with the
text offset of the first occurrence of this field in the formatted text.
object | the object to format. |
---|---|
buffer | the string buffer where the formatted string is appended to. |
field | on input: an optional alignment field; on output: the offsets of the alignment field in the formatted text. |
IllegalArgumentException | if the object cannot be formatted by this format. |
---|
Formats the specified object using the rules of this format and returns
an AttributedCharacterIterator
with the formatted string and no
attributes.
Subclasses should return an AttributedCharacterIterator
with the
appropriate attributes.
object | the object to format. |
---|
AttributedCharacterIterator
with the formatted object
and attributes.IllegalArgumentException | if the object cannot be formatted by this format. |
---|
Parses the specified string using the rules of this format.
string | the string to parse. |
---|
ParseException | if an error occurs during parsing. |
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Parses 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.
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. |
null
if there is
an error.