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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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/*
*******************************************************************************
* (C) Copyright IBM Corp. and others, 1996-2009 - All Rights Reserved *
* *
* The original version of this source code and documentation is copyrighted *
* and owned by IBM, These materials are provided under terms of a License *
* Agreement between IBM and Sun. This technology is protected by multiple *
* US and International patents. This notice and attribution to IBM may not *
* to removed. *
*******************************************************************************
*/
/* Written by Simon Montagu, Matitiahu Allouche
* (ported from C code written by Markus W. Scherer)
*/
package sun.text.bidi;
A BidiRun represents a sequence of characters at the same embedding level.
The Bidi algorithm decomposes a piece of text into sequences of characters
at the same embedding level, each such sequence is called a "run".
A BidiRun represents such a run by storing its essential properties,
but does not duplicate the characters which form the run.
The "limit" of the run is the position just after the
last character, i.e., one more than that position.
This class has no public constructor, and its members cannot be
modified by users.
See Also: - Bidi
/**
* A BidiRun represents a sequence of characters at the same embedding level.
* The Bidi algorithm decomposes a piece of text into sequences of characters
* at the same embedding level, each such sequence is called a "run".
*
* <p>A BidiRun represents such a run by storing its essential properties,
* but does not duplicate the characters which form the run.
*
* <p>The "limit" of the run is the position just after the
* last character, i.e., one more than that position.
*
* <p>This class has no public constructor, and its members cannot be
* modified by users.
*
* @see com.ibm.icu.text.Bidi
*/
class BidiRun {
int start; /* first logical position of the run */
int limit; /* last visual position of the run +1 */
int insertRemove; /* if >0, flags for inserting LRM/RLM before/after run,
if <0, count of bidi controls within run */
byte level;
/*
* Default constructor
*
* Note that members start and limit of a run instance have different
* meanings depending whether the run is part of the runs array of a Bidi
* object, or if it is a reference returned by getVisualRun() or
* getLogicalRun().
* For a member of the runs array of a Bidi object,
* - start is the first logical position of the run in the source text.
* - limit is one after the last visual position of the run.
* For a reference returned by getLogicalRun() or getVisualRun(),
* - start is the first logical position of the run in the source text.
* - limit is one after the last logical position of the run.
*/
BidiRun()
{
this(0, 0, (byte)0);
}
/*
* Constructor
*/
BidiRun(int start, int limit, byte embeddingLevel)
{
this.start = start;
this.limit = limit;
this.level = embeddingLevel;
}
/*
* Copy the content of a BidiRun instance
*/
void copyFrom(BidiRun run)
{
this.start = run.start;
this.limit = run.limit;
this.level = run.level;
this.insertRemove = run.insertRemove;
}
Get level of run
/**
* Get level of run
*/
byte getEmbeddingLevel()
{
return level;
}
Check if run level is even
Returns: true if the embedding level of this run is even, i.e. it is a
left-to-right run.
/**
* Check if run level is even
* @return true if the embedding level of this run is even, i.e. it is a
* left-to-right run.
*/
boolean isEvenRun()
{
return (level & 1) == 0;
}
}