Java Doc for ChoiceFormat.java in  » 6.0-JDK-Modules » j2me » java » text » Java Source Code / Java DocumentationJava Source Code and Java Documentation

 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));
 }
 

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));
 

 

 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.
See Also:   DecimalFormat
See Also:   MessageFormat
version:
   1.34, 10/10/06

Used to make half-open intervals.
See Also:   ChoiceFormat.previousDouble