jdk.text.ChoiceFormat — clojure-interop/java.text 1.0.5

A ChoiceFormat allows you to attach a format to a range of numbers. It is generally used in a MessageFormat for handling plurals. The choice is specified with an ascending list of doubles, where each item specifies a half-open interval up to the next item:

X matches j if and only if limit[j] ≤ X < limit[j+1]

If there is no match, then either the first or last index is used, depending on whether the number (X) is too low or too high. If the limit array is not in ascending order, the results of formatting will be incorrect. ChoiceFormat also accepts \u221E as equivalent to infinity(INF).

Note: ChoiceFormat differs from the other Format classes in that you create a ChoiceFormat object with a constructor (not with a getInstance style factory method). The factory methods aren't necessary because ChoiceFormat doesn't require any complex setup for a given locale. In fact, ChoiceFormat doesn't implement any locale specific behavior.

When creating a ChoiceFormat, you must specify an array of formats and an array of limits. The length of these arrays must be the same. For example,

limits = {1,2,3,4,5,6,7}
formats = {"Sun","Mon","Tue","Wed","Thur","Fri","Sat"}

limits = {0, 1, ChoiceFormat.nextDouble(1)}
formats = {"no files", "one file", "many files"}
(nextDouble can be used to get the next higher double, to
make the half-open interval.)

Here is a simple example that shows formatting and parsing:

double[] limits = {1,2,3,4,5,6,7}; String[] dayOfWeekNames = {"Sun","Mon","Tue","Wed","Thur","Fri","Sat"}; ChoiceFormat form = new ChoiceFormat(limits, dayOfWeekNames); ParsePosition status = new ParsePosition(0); for (double i = 0.0; i <= 8.0; +i) { status.setIndex(0); System.out.println(i " -> " form.format(i) " -> " form.parse(form.format(i),status)); }

Here is a more complex example, with a pattern format:

double[] filelimits = {0,1,2}; String[] filepart = {"are no files","is one file","are {2} files"}; ChoiceFormat fileform = new ChoiceFormat(filelimits, filepart); Format[] testFormats = {fileform, null, NumberFormat.getInstance()}; MessageFormat pattform = new MessageFormat("There {0} on {1}"); pattform.setFormats(testFormats); Object[] testArgs = {null, "ADisk", null}; for (int i = 0; i < 4; +i) { testArgs[0] = new Integer(i); testArgs[2] = testArgs[0]; System.out.println(pattform.format(testArgs)); }

Specifying a pattern for ChoiceFormat objects is fairly straightforward. For example:

ChoiceFormat fmt = new ChoiceFormat( "-1#is negative| 0#is zero or fraction | 1#is one |1.0<is 1+ |2#is two |2<is more than 2."); System.out.println("Formatter Pattern : " fmt.toPattern());

System.out.println("Format with -INF : " fmt.format(Double.NEGATIVE_INFINITY)); System.out.println("Format with -1.0 : " fmt.format(-1.0)); System.out.println("Format with 0 : " fmt.format(0)); System.out.println("Format with 0.9 : " fmt.format(0.9)); System.out.println("Format with 1.0 : " fmt.format(1)); System.out.println("Format with 1.5 : " fmt.format(1.5)); System.out.println("Format with 2 : " fmt.format(2)); System.out.println("Format with 2.1 : " fmt.format(2.1)); System.out.println("Format with NaN : " fmt.format(Double.NaN)); System.out.println("Format with INF : " fmt.format(Double.POSITIVE_INFINITY));

And the output result would be like the following:

Format with -INF : is negative Format with -1.0 : is negative Format with 0 : is zero or fraction Format with 0.9 : is zero or fraction Format with 1.0 : is one Format with 1.5 : is 1+ Format with 2 : is two Format with 2.1 : is more than 2. Format with NaN : is negative Format with INF : is more than 2.

Synchronization

Choice formats are 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.

*next-double clj

(*next-double d)

(*next-double d positive)

Finds the least double greater than d (if positive is true), or the greatest double less than d (if positive is false). If NaN, returns same value.

Does not affect floating-point flags, provided these member functions do not: Double.longBitsToDouble(long) Double.doubleToLongBits(double) Double.isNaN(double)

d - the reference value - double positive - true if the least double is desired; false otherwise - boolean

returns: the least or greater double value - double

*previous-double clj

(*previous-double d)

Finds the greatest double less than d. If NaN, returns same value.

d - the reference value - double

returns: the greatest double value less than d - double

->choice-format clj

(->choice-format new-pattern)

(->choice-format limits formats)

Constructor.

Constructs with the limits and the corresponding formats.

limits - limits in ascending order - double[] formats - corresponding format strings - java.lang.String[]

apply-pattern clj

(apply-pattern this new-pattern)

Sets the pattern.

new-pattern - See the class description. - java.lang.String

clone clj

(clone this)

Overrides Cloneable

returns: a clone of this instance. - java.lang.Object

equals clj

(equals this obj)

Equality comparision between two

obj - the reference object with which to compare. - java.lang.Object

returns: true if this object is the same as the obj argument; false otherwise. - boolean

format clj

(format this number to-append-to status)

Specialization of format. This method really calls format(double, StringBuffer, FieldPosition) thus the range of longs that are supported is only equal to the range that can be stored by double. This will never be a practical limitation.

number - the long number to format - long to-append-to - the StringBuffer to which the formatted text is to be appended - java.lang.StringBuffer status - the field position - java.text.FieldPosition

returns: the formatted StringBuffer - java.lang.StringBuffer

get-formats clj

(get-formats this)

Get the formats passed in the constructor.

returns: the formats. - java.lang.Object[]

get-limits clj

(get-limits this)

Get the limits passed in the constructor.

returns: the limits. - double[]

hash-code clj

(hash-code this)

Generates a hash code for the message format object.

returns: a hash code value for this object. - int

parse clj

(parse this text status)

Parses a Number from the input text.

text - the source text. - java.lang.String status - an input-output parameter. On input, the status.index field indicates the first character of the source text that should be parsed. On exit, if no error occurred, status.index is set to the first unparsed character in the source text. On exit, if an error did occur, status.index is unchanged and status.errorIndex is set to the first index of the character that caused the parse to fail. - java.text.ParsePosition

returns: A Number representing the value of the number parsed. - java.lang.Number

set-choices clj

(set-choices this limits formats)

Set the choices to be used in formatting.

limits - contains the top value that you want parsed with that format, and should be in ascending sorted order. When formatting X, the choice will be the i, where limit[i] ≤ X < limit[i+1]. If the limit array is not in ascending order, the results of formatting will be incorrect. - double[] formats - are the formats you want to use for each limit. They can be either Format objects or Strings. When formatting with object Y, if the object is a NumberFormat, then ((NumberFormat) Y).format(X) is called. Otherwise Y.toString() is called. - java.lang.String[]

to-pattern clj

(to-pattern this)

Gets the pattern.

returns: the pattern string - java.lang.String