com.itextpdf.io.font.otf

Class ContextualRule

java.lang.Object

com.itextpdf.io.font.otf.ContextualRule

Direct Known Subclasses:

ContextualPositionRule, ContextualSubstRule

public abstract class ContextualRule
extends Object

Constructor Summary

Constructors

Constructor and Description
ContextualRule()

Method Summary

Modifier and Type	Method and Description
int	getBacktrackContextLength() Gets the length of the backtrack context glyph sequence defined by this rule
abstract int	getContextLength() Gets the length of the context glyph sequence defined by this rule
int	getLookaheadContextLength() Gets the length of the lookahead context glyph sequence defined by this rule
boolean	isGlyphMatchesBacktrack(int glyphId, int atIdx) Checks if glyph line element matches element from backtrack sequence of the rule.
abstract boolean	isGlyphMatchesInput(int glyphId, int atIdx) Checks if glyph line element matches element from input sequence of the rule.
boolean	isGlyphMatchesLookahead(int glyphId, int atIdx) Checks if glyph line element matches element from lookahead sequence of the rule.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ContextualRule

public ContextualRule()

Method Detail

getContextLength

public abstract int getContextLength()

Gets the length of the context glyph sequence defined by this rule

Returns:

length of the context

isGlyphMatchesInput

public abstract boolean isGlyphMatchesInput(int glyphId,
                                            int atIdx)

Checks if glyph line element matches element from input sequence of the rule.

NOTE: rules do not contain the first element of the input sequence, the first element is defined by rule position in substitution table. Therefore atIdx shall not be 0.

Parameters:

glyphId - glyph code id

atIdx - index in the rule sequence. Shall be: 0 < atIdx < getContextLength()

Returns:

true if glyph matches element

getLookaheadContextLength

public int getLookaheadContextLength()

Gets the length of the lookahead context glyph sequence defined by this rule

Returns:

length of the lookahead context

getBacktrackContextLength

public int getBacktrackContextLength()

Gets the length of the backtrack context glyph sequence defined by this rule

Returns:

length of the backtrack context

isGlyphMatchesLookahead

public boolean isGlyphMatchesLookahead(int glyphId,
                                       int atIdx)

Checks if glyph line element matches element from lookahead sequence of the rule.

Parameters:

glyphId - glyph code id

atIdx - index in rule sequence. Shall be: 0 <= atIdx < getLookaheadContextLength()

Returns:

true if glyph matches element from lookahead sequence

isGlyphMatchesBacktrack

public boolean isGlyphMatchesBacktrack(int glyphId,
                                       int atIdx)

Checks if glyph line element matches element from backtrack sequence of the rule.

Parameters:

glyphId - glyph code id

atIdx - index in rule sequence. Shall be: 0 <= atIdx < getBacktrackContextLength()

Returns:

true if glyph matches element from backtrack sequence