scuffed-code/icu4c/source/common/unicode/usetiter.h
2004-04-01 06:52:12 +00:00

292 lines
8.4 KiB
C++

/*
**********************************************************************
* Copyright (c) 2002-2003, International Business Machines
* Corporation and others. All Rights Reserved.
**********************************************************************
*/
#ifndef USETITER_H
#define USETITER_H
#include "unicode/utypes.h"
#include "unicode/uobject.h"
#include "unicode/unistr.h"
U_NAMESPACE_BEGIN
class UnicodeSet;
class UnicodeString;
/**
* UnicodeSetIterator iterates over the contents of a UnicodeSet. It
* iterates over either code points or code point ranges. After all
* code points or ranges have been returned, it returns the
* multicharacter strings of the UnicodSet, if any.
*
* <p>To iterate over code points, use a loop like this:
* <pre>
* UnicodeSetIterator it(set);
* while (set.next()) {
* if (set.isString()) {
* processString(set.getString());
* } else {
* processCodepoint(set.getCodepoint());
* }
* }
* </pre>
*
* <p>To iterate over code point ranges, use a loop like this:
* <pre>
* UnicodeSetIterator it(set);
* while (it.nextRange()) {
* if (it.isString()) {
* processString(it.getString());
* } else {
* processCodepointRange(it.getCodepoint(), it.getCodepointEnd());
* }
* }
* </pre>
* @author M. Davis
* @stable ICU 2.4
*/
class U_COMMON_API UnicodeSetIterator : public UObject {
protected:
/**
* Value of <tt>codepoint</tt> if the iterator points to a string.
* If <tt>codepoint == IS_STRING</tt>, then examine
* <tt>string</tt> for the current iteration result.
* @stable ICU 2.4
*/
enum { IS_STRING = -1 };
/**
* Current code point, or the special value <tt>IS_STRING</tt>, if
* the iterator points to a string.
* @stable ICU 2.4
*/
UChar32 codepoint;
/**
* When iterating over ranges using <tt>nextRange()</tt>,
* <tt>codepointEnd</tt> contains the inclusive end of the
* iteration range, if <tt>codepoint != IS_STRING</tt>. If
* iterating over code points using <tt>next()</tt>, or if
* <tt>codepoint == IS_STRING</tt>, then the value of
* <tt>codepointEnd</tt> is undefined.
* @stable ICU 2.4
*/
UChar32 codepointEnd;
/**
* If <tt>codepoint == IS_STRING</tt>, then <tt>string</tt> points
* to the current string. If <tt>codepoint != IS_STRING</tt>, the
* value of <tt>string</tt> is undefined.
* @stable ICU 2.4
*/
const UnicodeString* string;
public:
/**
* Create an iterator over the given set. The iterator is valid
* only so long as <tt>set</tt> is valid.
* @param set set to iterate over
* @stable ICU 2.4
*/
UnicodeSetIterator(const UnicodeSet& set);
/**
* Create an iterator over nothing. <tt>next()</tt> and
* <tt>nextRange()</tt> return false. This is a convenience
* constructor allowing the target to be set later.
* @stable ICU 2.4
*/
UnicodeSetIterator();
/**
* Destructor.
* @stable ICU 2.4
*/
virtual ~UnicodeSetIterator();
/**
* Returns true if the current element is a string. If so, the
* caller can retrieve it with <tt>getString()</tt>. If this
* method returns false, the current element is a code point or
* code point range, depending on whether <tt>next()</tt> or
* <tt>nextRange()</tt> was called, and the caller can retrieve it
* with <tt>getCodepoint()</tt> and, for a range,
* <tt>getCodepointEnd()</tt>.
* @stable ICU 2.4
*/
inline UBool isString() const;
/**
* Returns the current code point, if <tt>isString()</tt> returned
* false. Otherwise returns an undefined result.
* @stable ICU 2.4
*/
inline UChar32 getCodepoint() const;
/**
* Returns the end of the current code point range, if
* <tt>isString()</tt> returned false and <tt>nextRange()</tt> was
* called. Otherwise returns an undefined result.
* @stable ICU 2.4
*/
inline UChar32 getCodepointEnd() const;
/**
* Returns the current string, if <tt>isString()</tt> returned
* true. Otherwise returns an undefined result.
* @stable ICU 2.4
*/
inline const UnicodeString& getString() const;
/**
* Returns the next element in the set, either a single code point
* or a string. If there are no more elements in the set, return
* false. If <tt>codepoint == IS_STRING</tt>, the value is a
* string in the <tt>string</tt> field. Otherwise the value is a
* single code point in the <tt>codepoint</tt> field.
*
* <p>The order of iteration is all code points in sorted order,
* followed by all strings sorted order. <tt>codepointEnd</tt> is
* undefined after calling this method. <tt>string</tt> is
* undefined unless <tt>codepoint == IS_STRING</tt>. Do not mix
* calls to <tt>next()</tt> and <tt>nextRange()</tt> without
* calling <tt>reset()</tt> between them. The results of doing so
* are undefined.
*
* @return true if there was another element in the set and this
* object contains the element.
* @stable ICU 2.4
*/
UBool next();
/**
* Returns the next element in the set, either a code point range
* or a string. If there are no more elements in the set, return
* false. If <tt>codepoint == IS_STRING</tt>, the value is a
* string in the <tt>string</tt> field. Otherwise the value is a
* range of one or more code points from <tt>codepoint</tt> to
* <tt>codepointeEnd</tt> inclusive.
*
* <p>The order of iteration is all code points ranges in sorted
* order, followed by all strings sorted order. Ranges are
* disjoint and non-contiguous. <tt>string</tt> is undefined
* unless <tt>codepoint == IS_STRING</tt>. Do not mix calls to
* <tt>next()</tt> and <tt>nextRange()</tt> without calling
* <tt>reset()</tt> between them. The results of doing so are
* undefined.
*
* @return true if there was another element in the set and this
* object contains the element.
* @stable ICU 2.4
*/
UBool nextRange();
/**
* Sets this iterator to visit the elements of the given set and
* resets it to the start of that set. The iterator is valid only
* so long as <tt>set</tt> is valid.
* @param set the set to iterate over.
* @stable ICU 2.4
*/
void reset(const UnicodeSet& set);
/**
* Resets this iterator to the start of the set.
* @stable ICU 2.4
*/
void reset();
/**
* ICU "poor man's RTTI", returns a UClassID for this class.
*
* @stable ICU 2.4
*/
static UClassID getStaticClassID();
/**
* ICU "poor man's RTTI", returns a UClassID for the actual class.
*
* @stable ICU 2.4
*/
virtual UClassID getDynamicClassID() const;
// ======================= PRIVATES ===========================
protected:
// endElement and nextElements are really UChar32's, but we keep
// them as signed int32_t's so we can do comparisons with
// endElement set to -1. Leave them as int32_t's.
/** The set
* @stable ICU 2.4
*/
const UnicodeSet* set;
/** End range
* @stable ICU 2.4
*/
int32_t endRange;
/** Range
* @stable ICU 2.4
*/
int32_t range;
/** End element
* @stable ICU 2.4
*/
int32_t endElement;
/** Next element
* @stable ICU 2.4
*/
int32_t nextElement;
//UBool abbreviated;
/** Next string
* @stable ICU 2.4
*/
int32_t nextString;
/** String count
* @stable ICU 2.4
*/
int32_t stringCount;
/** Copy constructor. Disallowed.
* @stable ICU 2.4
*/
UnicodeSetIterator(const UnicodeSetIterator&); // disallow
/** Assignment operator. Disallowed.
* @stable ICU 2.4
*/
UnicodeSetIterator& operator=(const UnicodeSetIterator&); // disallow
/** Load range
* @stable ICU 2.4
*/
virtual void loadRange(int32_t range);
};
inline UBool UnicodeSetIterator::isString() const {
return codepoint == (UChar32)IS_STRING;
}
inline UChar32 UnicodeSetIterator::getCodepoint() const {
return codepoint;
}
inline UChar32 UnicodeSetIterator::getCodepointEnd() const {
return codepointEnd;
}
inline const UnicodeString& UnicodeSetIterator::getString() const {
return *string;
}
U_NAMESPACE_END
#endif