The UnicodeSet class is not designed to be subclassed. * *
UnicodeSet supports two APIs. The first is the
* operand API that allows the caller to modify the value of
* a UnicodeSet object. It conforms to Java 2's
* java.util.Set interface, although
* UnicodeSet does not actually implement that
* interface. All methods of Set are supported, with the
* modification that they take a character range or single character
* instead of an Object, and they take a
* UnicodeSet instead of a Collection. The
* operand API may be thought of in terms of boolean logic: a boolean
* OR is implemented by add, a boolean AND is implemented
* by retain, a boolean XOR is implemented by
* complement taking an argument, and a boolean NOT is
* implemented by complement with no argument. In terms
* of traditional set theory function names, add is a
* union, retain is an intersection, remove
* is an asymmetric difference, and complement with no
* argument is a set complement with respect to the superset range
* MIN_VALUE-MAX_VALUE
*
*
The second API is the
* applyPattern()/toPattern() API from the
* java.text.Format-derived classes. Unlike the
* methods that add characters, add categories, and control the logic
* of the set, the method applyPattern() sets all
* attributes of a UnicodeSet at once, based on a
* string pattern.
*
*
Pattern syntax
* * Patterns are accepted by the constructors and the *applyPattern() methods and returned by the
* toPattern() method. These patterns follow a syntax
* similar to that employed by version 8 regular expression character
* classes. Here are some simple examples:
*
* \htmlonly\endhtmlonly **
* * []No characters ** * [a]The character 'a' ** ** [ae]The characters 'a' and 'e' ** ** [a-e]The characters 'a' through 'e' inclusive, in Unicode code * point order ** [\\u4