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/*
**********************************************************************
* Copyright (C) 1998-2008, International Business Machines
* Corporation and others. All Rights Reserved.
**********************************************************************
*/
#ifndef __LEINSERTIONLIST_H
#define __LEINSERTIONLIST_H
#include "LETypes.h"
U_NAMESPACE_BEGIN
struct InsertionRecord;
/**
* This class encapsulates the callback used by <code>LEInsertionList</code>
* to apply an insertion from the insertion list.
*
* @internal
*/
class U_LAYOUT_API LEInsertionCallback
{
public:
/**
* This method will be called by <code>LEInsertionList::applyInsertions</code> for each
* entry on the insertion list.
*
* @param atPosition the position of the insertion
* @param count the number of glyphs to insert
* @param newGlyphs the address of the glyphs to insert
*
* @return <code>TRUE</code> if <code>LEInsertions::applyInsertions</code> should
* stop after applying this insertion.
*
* @internal
*/
virtual le_bool applyInsertion(le_int32 atPosition, le_int32 count, LEGlyphID newGlyphs[]) = 0;
/**
* The destructor
*/
virtual ~LEInsertionCallback();
};
/**
* This class is used to keep track of insertions to an array of
* <code>LEGlyphIDs</code>. The insertions are kept on a linked
* list of <code>InsertionRecords</code> so that the glyph array
* doesn't have to be grown for each insertion. The insertions are
* stored on the list from leftmost to rightmost to make it easier
* to do the insertions.
*
* The insertions are applied to the array by calling the
* <code>applyInsertions</code> method, which calls a client
* supplied <code>LEInsertionCallback</code> object to actually
* apply the individual insertions.
*
* @internal
*/
class LEInsertionList : public UObject
{
public:
/**
* Construct an empty insertion list.
*
* @param rightToLeft <code>TRUE</code> if the glyphs are stored
* in the array in right to left order.
*
* @internal
*/
LEInsertionList(le_bool rightToLeft);
/**
* The destructor.
*/
~LEInsertionList();
/**
* Add an entry to the insertion list.
*
* @param position the glyph at this position in the array will be
* replaced by the new glyphs.
* @param count the number of new glyphs
* @param success set to an error code if the auxillary data cannot be retrieved.
*
* @return the address of an array in which to store the new glyphs. This will
* <em>not</em> be in the glyph array.
*
* @internal
*/
LEGlyphID *insert(le_int32 position, le_int32 count, LEErrorCode &success);
/**
* Return the number of new glyphs that have been inserted.
*
* @return the number of new glyphs which have been inserted
*
* @internal
*/
le_int32 getGrowAmount();
/**
* Call the <code>LEInsertionCallback</code> once for each
* entry on the insertion list.
*
* @param callback the <code>LEInsertionCallback</code> to call for each insertion.
*
* @return <code>TRUE</code> if <code>callback</code> returned <code>TRUE</code> to
* terminate the insertion list processing.
*
* @internal
*/
le_bool applyInsertions(LEInsertionCallback *callback);
/**
* Empty the insertion list and free all associated
* storage.
*
* @internal
*/
void reset();
/**
* ICU "poor man's RTTI", returns a UClassID for the actual class.
*
* @stable ICU 2.8
*/
virtual UClassID getDynamicClassID() const;
/**
* ICU "poor man's RTTI", returns a UClassID for this class.
*
* @stable ICU 2.8
*/
static UClassID getStaticClassID();
private:
/**
* The head of the insertion list.
*
* @internal
*/
InsertionRecord *head;
/**
* The tail of the insertion list.
*
* @internal
*/
InsertionRecord *tail;
/**
* The total number of new glyphs on the insertion list.
*
* @internal
*/
le_int32 growAmount;
/**
* Set to <code>TRUE</code> if the glyphs are in right
* to left order. Since we want the rightmost insertion
* to be first on the list, we need to append the
* insertions in this case. Otherwise they're prepended.
*
* @internal
*/
le_bool append;
};
U_NAMESPACE_END
#endif