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:
*
* ** * Any character may be preceded by a backslash in order to remove any special * meaning. White space characters, as defined by UCharacter.isWhitespace(), are * ignored, unless they are escaped. * **
** ** pattern :=* ('[' '^'? item* ']') | * property* ** item :=* char | (char '-' char) | pattern-expr
** ** pattern-expr :=* pattern | pattern-expr pattern | * pattern-expr op pattern
** ** op :=* '&' | '-'
** ** special :=* '[' | ']' | '-'
** ** char :=any character that is not *specialany character
* | ('\u005C')
* | ('\u005Cu' hex hex hex hex)
** ** hex :=any character for which * *Character.digit(c, 16)* returns a non-negative result* ** property :=a Unicode property set pattern *
**
** *Legend: **
** ** a := b* * amay be replaced byb* ** a?* zero or one instance of *a
** ** a** one or more instances of *a
** ** a | b* either *aorb
** ** 'a'* the literal string between the quotes *
Property patterns specify a set of characters having a certain * property as defined by the Unicode standard. Both the POSIX-like * "[:Lu:]" and the Perl-like syntax "\p{Lu}" are recognized. For a * complete list of supported property patterns, see the User's Guide * for UnicodeSet at * * http://oss.software.ibm.com/icu/userguide/unicodeset.html. * Actual determination of property data is defined by the underlying * Unicode database as implemented by UCharacter. * *
Patterns specify individual characters, ranges of characters, and * Unicode property sets. When elements are concatenated, they * specify their union. To complement a set, place a '^' immediately * after the opening '['. Property patterns are inverted by modifying * their delimiters; "[:^foo]" and "\P{foo}". In any other location, * '^' has no special meaning. * *
Ranges are indicated by placing two a '-' between two * characters, as in "a-z". This specifies the range of all * characters from the left to the right, in Unicode order. If the * left character is greater than or equal to the * right character it is a syntax error. If a '-' occurs as the first * character after the opening '[' or '[^', or if it occurs as the * last character before the closing ']', then it is taken as a * literal. Thus "[a\u005C-b]", "[-ab]", and "[ab-]" all indicate the same * set of three characters, 'a', 'b', and '-'. * *
Sets may be intersected using the '&' operator or the asymmetric * set difference may be taken using the '-' operator, for example, * "[[:L:]&[\u005Cu0000-\u005Cu0FFF]]" indicates the set of all Unicode letters * with values less than 4096. Operators ('&' and '|') have equal * precedence and bind left-to-right. Thus * "[[:L:]-[a-z]-[\u005Cu0100-\u005Cu01FF]]" is equivalent to * "[[[:L:]-[a-z]]-[\u005Cu0100-\u005Cu01FF]]". This only really matters for * difference; intersection is commutative. * *
[a] | The set containing 'a' * |
[a-z] | The set containing 'a' * through 'z' and all letters in between, in Unicode order * |
[^a-z] | The set containing * all characters but 'a' through 'z', * that is, U+0000 through 'a'-1 and 'z'+1 through U+10FFFF * |
[[pat1][pat2]]
* | The union of sets specified by pat1 and pat2 * |
[[pat1]&[pat2]]
* | The intersection of sets specified by pat1 and pat2 * |
[[pat1]-[pat2]]
* | The asymmetric difference of sets specified by pat1 and * pat2 * |
[:Lu:] or \p{Lu}
* | The set of characters having the specified * Unicode property; in * this case, Unicode uppercase letters * |
[:^Lu:] or \P{Lu}
* | The set of characters not having the given * Unicode property * |
end >
* start then an empty set is created.
*
* @param start first character, inclusive, of range
* @param end last character, inclusive, of range
*/
UnicodeSet(UChar32 start, UChar32 end);
/**
* Constructs a set from the given pattern. See the class
* description for the syntax of the pattern language.
* @param pattern a string specifying what characters are in the set
* @exception IllegalArgumentException if the pattern
* contains a syntax error.
* @stable
*/
UnicodeSet(const UnicodeString& pattern,
UErrorCode& status);
/**
* DEPRECATED Constructs a set from the given Unicode character category.
* @param category an integer indicating the character category as
* defined in uchar.h.
* @deprecated To be removed after 2002-DEC-31
*/
UnicodeSet(int8_t category, UErrorCode& status);
/**
* Constructs a set that is identical to the given UnicodeSet.
* @stable
*/
UnicodeSet(const UnicodeSet& o);
/**
* Destructs the set.
* @stable
*/
virtual ~UnicodeSet();
/**
* Assigns this object to be a copy of another.
* @stable
*/
UnicodeSet& operator=(const UnicodeSet& o);
/**
* Compares the specified object with this set for equality. Returns
* true if the two sets
* have the same size, and every member of the specified set is
* contained in this set (or equivalently, every member of this set is
* contained in the specified set).
*
* @param o set to be compared for equality with this set.
* @return true if the specified set is equal to this set.
* @stable
*/
virtual UBool operator==(const UnicodeSet& o) const;
/**
* Compares the specified object with this set for equality. Returns
* true if the specified set is not equal to this set.
* @stable
*/
UBool operator!=(const UnicodeSet& o) const;
/**
* Returns a copy of this object. All UnicodeFunctor objects have
* to support cloning in order to allow classes using
* UnicodeFunctors, such as Transliterator, to implement cloning.
* @draft ICU 2.0
*/
virtual UnicodeFunctor* clone() const;
/**
* Returns the hash code value for this set.
*
* @return the hash code value for this set.
* @see Object#hashCode()
* @stable
*/
virtual int32_t hashCode(void) const;
//----------------------------------------------------------------
// Public API
//----------------------------------------------------------------
/**
* Make this object represent the range start - end.
* If end > start then this object is set to an
* an empty range.
*
* @param start first character in the set, inclusive
* @rparam end last character in the set, inclusive
*/
void set(UChar32 start, UChar32 end);
/**
* Return true if the given position, in the given pattern, appears
* to be the start of a UnicodeSet pattern.
*/
static UBool resemblesPattern(const UnicodeString& pattern,
int32_t pos);
/**
* Modifies this set to represent the set specified by the given
* pattern, optionally ignoring white space. See the class
* description for the syntax of the pattern language.
* @param pattern a string specifying what characters are in the set
* @exception IllegalArgumentException if the pattern
* contains a syntax error.
* @stable
*/
virtual void applyPattern(const UnicodeString& pattern,
UErrorCode& status);
/**
* Returns a string representation of this set. If the result of
* calling this function is passed to a UnicodeSet constructor, it
* will produce another set that is equal to this one.
* @param result the string to receive the rules. Previous
* contents will be deleted.
* @param escapeUnprintable if TRUE then convert unprintable
* character to their hex escape representations, \uxxxx or
* \Uxxxxxxxx. Unprintable characters are those other than
* U+000A, U+0020..U+007E.
* @draft ICU 2.0
*/
virtual UnicodeString& toPattern(UnicodeString& result,
UBool escapeUnprintable = FALSE) const;
/**
* Returns the number of elements in this set (its cardinality),
* n, where 0 <= n <= 65536.
*
* @return the number of elements in this set (its cardinality).
* @stable
*/
virtual int32_t size(void) const;
/**
* Returns true if this set contains no elements.
*
* @return true if this set contains no elements.
* @stable
*/
virtual UBool isEmpty(void) const;
/**
* Returns true if this set contains the specified range
* of chars.
*
* @return true if this set contains the specified range
* of chars.
* @draft ICU 2.0
*/
virtual UBool contains(UChar32 start, UChar32 end) const;
/**
* Returns true if this set contains the specified char.
*
* @return true if this set contains the specified char.
* @draft ICU 2.0
*/
virtual UBool contains(UChar32 c) const;
/**
* Implement UnicodeMatcher::matches()
*/
UMatchDegree matches(const Replaceable& text,
int32_t& offset,
int32_t limit,
UBool incremental);
/**
* Returns the index of the given character within this set, where
* the set is ordered by ascending code point. If the character
* is not in this set, return -1. The inverse of this method is
* charAt().
* @return an index from 0..size()-1, or -1
*/
int32_t indexOf(UChar32 c) const;
/**
* Returns the character at the given index within this set, where
* the set is ordered by ascending code point. If the index is
* out of range, return (UChar32)-1. The inverse of this method is
* indexOf().
* @param index an index from 0..size()-1
* @return the character at the given index, or (UChar32)-1.
*/
UChar32 charAt(int32_t index) const;
/**
* Adds the specified range to this set if it is not already
* present. If this set already contains the specified range,
* the call leaves this set unchanged. If end > start
* then an empty range is added, leaving the set unchanged.
* This is equivalent to a boolean logic OR, or a set UNION.
*
* @param start first character, inclusive, of range to be added
* to this set.
* @param end last character, inclusive, of range to be added
* to this set.
* @draft ICU 2.0
*/
virtual void add(UChar32 start, UChar32 end);
/**
* Adds the specified character to this set if it is not already
* present. If this set already contains the specified character,
* the call leaves this set unchanged.
* @draft ICU 2.0
*/
void add(UChar32 c);
/**
* Retain only the elements in this set that are contained in the
* specified range. If end > start then an empty range is
* retained, leaving the set empty. This is equivalent to
* a boolean logic AND, or a set INTERSECTION.
*
* @param start first character, inclusive, of range to be retained
* to this set.
* @param end last character, inclusive, of range to be retained
* to this set.
* @draft ICU 2.0
*/
virtual void retain(UChar32 start, UChar32 end);
/**
* Retain the specified character from this set if it is present.
* @draft ICU 2.0
*/
void retain(UChar32 c);
/**
* Removes the specified range from this set if it is present.
* The set will not contain the specified range once the call
* returns. If end > start then an empty range is
* removed, leaving the set unchanged.
*
* @param start first character, inclusive, of range to be removed
* from this set.
* @param end last character, inclusive, of range to be removed
* from this set.
* @draft ICU 2.0
*/
virtual void remove(UChar32 start, UChar32 end);
/**
* Removes the specified character from this set if it is present.
* The set will not contain the specified range once the call
* returns.
* @draft ICU 2.0
*/
void remove(UChar32 c);
/**
* Inverts this set. This operation modifies this set so that
* its value is its complement. This is equivalent to
* complement(MIN_VALUE, MAX_VALUE).
* @stable
*/
virtual void complement(void);
/**
* Complements the specified range in this set. Any character in
* the range will be removed if it is in this set, or will be
* added if it is not in this set. If end > start
* then an empty range is complemented, leaving the set unchanged.
* This is equivalent to a boolean logic XOR.
*
* @param start first character, inclusive, of range to be removed
* from this set.
* @param end last character, inclusive, of range to be removed
* from this set.
* @draft ICU 2.0
*/
virtual void complement(UChar32 start, UChar32 end);
/**
* Complements the specified character in this set. The character
* will be removed if it is in this set, or will be added if it is
* not in this set.
* @draft ICU 2.0
*/
void complement(UChar32 c);
/**
* Returns true if the specified set is a subset
* of this set.
*
* @param c set to be checked for containment in this set.
* @return true if this set contains all of the elements of the
* specified set.
* @stable
*/
virtual UBool containsAll(const UnicodeSet& c) const;
private:
friend class NormalizationTransliterator;
// TODO: Make this public
/**
* Return TRUE if every character in s is in this set.
*/
UBool containsAll(const UnicodeString& s) const;
public:
/**
* Adds all of the elements in the specified set to this set if
* they're not already present. This operation effectively
* modifies this set so that its value is the union of the two
* sets. The behavior of this operation is unspecified if the specified
* collection is modified while the operation is in progress.
*
* @param c set whose elements are to be added to this set.
* @see #add(char, char)
* @stable
*/
virtual void addAll(const UnicodeSet& c);
/**
* Retains only the elements in this set that are contained in the
* specified set. In other words, removes from this set all of
* its elements that are not contained in the specified set. This
* operation effectively modifies this set so that its value is
* the intersection of the two sets.
*
* @param c set that defines which elements this set will retain.
* @stable
*/
virtual void retainAll(const UnicodeSet& c);
/**
* Removes from this set all of its elements that are contained in the
* specified set. This operation effectively modifies this
* set so that its value is the asymmetric set difference of
* the two sets.
*
* @param c set that defines which elements will be removed from
* this set.
* @stable
*/
virtual void removeAll(const UnicodeSet& c);
/**
* Complements in this set all elements contained in the specified
* set. Any character in the other set will be removed if it is
* in this set, or will be added if it is not in this set.
*
* @param c set that defines which elements will be xor'ed from
* this set.
*/
virtual void complementAll(const UnicodeSet& c);
/**
* Removes all of the elements from this set. This set will be
* empty after this call returns.
* @stable
*/
virtual void clear(void);
/**
* Iteration method that returns the number of ranges contained in
* this set.
* @see #getRangeStart
* @see #getRangeEnd
*/
virtual int32_t getRangeCount(void) const;
/**
* Iteration method that returns the first character in the
* specified range of this set.
* @see #getRangeCount
* @see #getRangeEnd
*/
virtual UChar32 getRangeStart(int32_t index) const;
/**
* Iteration method that returns the last character in the
* specified range of this set.
* @see #getRangeStart
* @see #getRangeEnd
*/
virtual UChar32 getRangeEnd(int32_t index) const;
/**
* Reallocate this objects internal structures to take up the least
* possible space, without changing this object's value.
*/
virtual void compact();
/**
* Return the class ID for this class. This is useful only for
* comparing to a return value from getDynamicClassID(). For example:
*
* . Base* polymorphic_pointer = createPolymorphicObject();
* . if (polymorphic_pointer->getDynamicClassID() ==
* . Derived::getStaticClassID()) ...
*
* @return The class ID for all objects of this class.
* @stable
*/
static UClassID getStaticClassID(void) { return (UClassID)&fgClassID; }
/**
* Implement UnicodeFunctor API.
*
* @return The class ID for this object. All objects of a given
* class have the same class ID. Objects of other classes have
* different class IDs.
*/
virtual UClassID getDynamicClassID(void) const { return getStaticClassID(); };
private:
static const char fgClassID;
private:
//----------------------------------------------------------------
// RuleBasedTransliterator support
//----------------------------------------------------------------
friend class Transliterator;
friend class TransliteratorParser;
friend class TransliteratorIDParser;
friend class TransliterationRule;
/**
* Constructs a set from the given pattern. See the class description
* for the syntax of the pattern language.
* @param pattern a string specifying what characters are in the set
* @param pos on input, the position in pattern at which to start parsing.
* On output, the position after the last character parsed.
* @param varNameToChar a mapping from variable names (String) to characters
* (Character). May be null. If varCharToSet is non-null, then names may
* map to either single characters or sets, depending on whether a mapping
* exists in varCharToSet. If varCharToSet is null then all names map to
* single characters.
* @param varCharToSet a mapping from characters (Character objects from
* varNameToChar) to UnicodeSet objects. May be null. Is only used if
* varNameToChar is also non-null.
* @exception IllegalArgumentException if the pattern
* contains a syntax error.
*/
UnicodeSet(const UnicodeString& pattern, ParsePosition& pos,
const SymbolTable& symbols,
UErrorCode& status);
/**
* Constructs a set from the given pattern. Identical to the
* 4-parameter ParsePosition contstructor, but does not take a
* SymbolTable, and does not recognize embedded variables.
*/
UnicodeSet(const UnicodeString& pattern, ParsePosition& pos,
UErrorCode& status);
/**
* Returns true if this set contains any character whose low byte
* is the given value. This is used by RuleBasedTransliterator for
* indexing.
*/
virtual UBool matchesIndexValue(uint8_t v) const;
private:
//----------------------------------------------------------------
// Implementation: Pattern parsing
//----------------------------------------------------------------
/**
* Parses the given pattern, starting at the given position. The
* character at pattern.charAt(pos.getIndex()) must be '[', or the
* parse fails. Parsing continues until the corresponding closing
* ']'. If a syntax error is encountered between the opening and
* closing brace, the parse fails. Upon return from a successful
* parse, the ParsePosition is updated to point to the character
* following the closing ']', and a StringBuffer containing a
* pairs list for the parsed pattern is returned. This method calls
* itself recursively to parse embedded subpatterns.
*
* @param pattern the string containing the pattern to be parsed.
* The portion of the string from pos.getIndex(), which must be a
* '[', to the corresponding closing ']', is parsed.
* @param pos upon entry, the position at which to being parsing.
* The character at pattern.charAt(pos.getIndex()) must be a '['.
* Upon return from a successful parse, pos.getIndex() is either
* the character after the closing ']' of the parsed pattern, or
* pattern.length() if the closing ']' is the last character of
* the pattern string.
* @return a StringBuffer containing a pairs list for the parsed
* substring of pattern
* @exception IllegalArgumentException if the parse fails.
*/
void applyPattern(const UnicodeString& pattern,
ParsePosition& pos,
const SymbolTable* symbols,
UErrorCode& status);
//----------------------------------------------------------------
// Implementation: Utility methods
//----------------------------------------------------------------
void ensureCapacity(int32_t newLen);
void ensureBufferCapacity(int32_t newLen);
void swapBuffers(void);
void _applyPattern(const UnicodeString& pattern,
ParsePosition& pos,
const SymbolTable* symbols,
UnicodeString& rebuiltPat,
UErrorCode& status);
UnicodeString& _toPattern(UnicodeString& result,
UBool escapeUnprintable) const;
UnicodeString& _generatePattern(UnicodeString& result,
UBool escapeUnprintable) const;
static void _appendToPat(UnicodeString& buf, UChar32 c, UBool escapeUnprintable);
//----------------------------------------------------------------
// Implementation: Fundamental operators
//----------------------------------------------------------------
void exclusiveOr(const UChar32* other, int32_t otherLen, int8_t polarity);
void add(const UChar32* other, int32_t otherLen, int8_t polarity);
void retain(const UChar32* other, int32_t otherLen, int8_t polarity);
};
inline UBool UnicodeSet::operator!=(const UnicodeSet& o) const {
return !operator==(o);
}
U_NAMESPACE_END
#endif