All Packages  Class Hierarchy  This Package  Previous  Next  Index

Class java.text.ChoiceFormat

java.lang.Object
   |
   +----java.text.Format
           |
           +----java.text.NumberFormat
                   |
                   +----java.text.ChoiceFormat

public class ChoiceFormat

extends NumberFormat

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

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[] monthNames = {"Sun","Mon","Tue","Wed","Thur","Fri","Sat"};
 ChoiceFormat form = new ChoiceFormat(limits, monthNames);
 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));
 }
 

 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));
 }
 

See Also:

DecimalFormat, MessageFormat

ChoiceFormat(double[], String[])

Constructs with the limits and the corresponding formats.

ChoiceFormat(String)

Constructs with limits and corresponding formats based on the pattern.

applyPattern(String)

Sets the pattern.

clone()

Overrides Cloneable

equals(Object)

Equality comparision between two

format(double, StringBuffer, FieldPosition)

Specialization of format.

format(long, StringBuffer, FieldPosition)

Specialization of format.

getFormats()

Get the formats passed in the constructor.

getLimits()

Get the limits passed in the constructor.

hashCode()

Generates a hash code for the message format object.

nextDouble(double)

Finds the least double greater than d.

nextDouble(double, boolean)

parse(String, ParsePosition)

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

previousDouble(double)

Finds the greatest double less than d.

setChoices(double[], String[])

Set the choices to be used in formatting.

toPattern()

Gets the pattern.

 public ChoiceFormat(String newPattern)

Constructs with limits and corresponding formats based on the pattern.

 public ChoiceFormat(double limits[],
                     String formats[])

Constructs with the limits and the corresponding formats.

See Also:

setChoices

 public void applyPattern(String newPattern)

Sets the pattern.

Parameters:

newPattern - See the class description.

 public String toPattern()

Gets the pattern.

 public void setChoices(double limits[],
                        String formats[])

Set the choices to be used in formatting.

Parameters:

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].

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.

 public double[] getLimits()

Get the limits passed in the constructor.

Returns:

the limits.

 public Object[] getFormats()

Get the formats passed in the constructor.

Returns:

the formats.

 public StringBuffer format(long number,
                            StringBuffer toAppendTo,
                            FieldPosition 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.

Overrides:

format in class NumberFormat

 public StringBuffer format(double number,
                            StringBuffer toAppendTo,
                            FieldPosition status)

Specialization of format.

Overrides:

format in class NumberFormat

 public Number parse(String text,
                     ParsePosition status)

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

Overrides:

parse in class NumberFormat

 public static final double nextDouble(double d)

Finds the least double greater than d. If NaN, returns same value.

Used to make half-open intervals.

See Also:

previousDouble

 public static final double previousDouble(double d)

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

See Also:

nextDouble

 public Object clone()

Overrides Cloneable

Overrides:

clone in class NumberFormat

 public int hashCode()

Generates a hash code for the message format object.

Overrides:

hashCode in class NumberFormat

 public boolean equals(Object obj)

Equality comparision between two

Overrides:

equals in class NumberFormat

 public static double nextDouble(double d,
                                 boolean positive)

All Packages  Class Hierarchy  This Package  Previous  Next  Index