Class java.text.RuleBasedCollator





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Class java.text.RuleBasedCollator


java.lang.Object
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+----java.text.Collator
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+----java.text.RuleBasedCollator



public class RuleBasedCollator
extends Collator

The RuleBasedCollator class is a concrete subclass of
Collator that provides a simple, data-driven, table collator.
With this class you can create a customized table-based Collator.
RuleBasedCollator maps characters to sort keys.

RuleBasedCollator has the following restrictions
for efficiency (other subclasses may be used for more complex languages) :

If a French secondary ordering is specified it applies to the
whole collator object.
All non-mentioned Unicode characters are at the end of the
collation order.
Private use characters are treated as identical. The private
use area in Unicode is 0xE800-0xF8FF.


The collation table is composed of a list of collation rules, where each
rule is of three forms:

< modifier >
< relation > < text-argument >
< reset > < text-argument >

The following demonstrates how to create your own collation rules:

Text-Argument: A text-argument is any sequence of
characters, excluding special characters (that is, whitespace
characters and the characters used in modifier, relation and reset).
If those characters are desired, you can put them in single quotes
(e.g. ampersand => '&'). Note that unquoted white space characters
are ignored; e.g. b c is treated as bc.
Modifier: There is a single modifier
which is used to specify that all accents (secondary differences) are
backwards.
'@' : Indicates that accents are sorted backwards, as in French.
Relation: The relations are the following:

'