org.apache.batik.gvt.text

Class ArabicTextHandler

public class ArabicTextHandler extends Object

Handles the processing of arabic text. In particular it determines the form each arabic char should take. It also contains methods for substituting plain arabic glyphs with their shaped forms. This is needed when the arabic text is rendered using an AWT font.
Method Summary
static booleanarabicChar(char c)
Returns true if the char is a standard arabic char. (ie. within the range U+0600 - U+6FF)
static booleanarabicCharTransparent(char c)
Returns true if the char is transparent.
static AttributedStringassignArabicForms(AttributedString as)
If the AttributedString contains any arabic chars, assigns an arabic form attribute, i.e. initial|medial|terminal|isolated, to each arabic char.
static booleancharStartsLigature(char c)
Returns true if a ligature exists that starts with the specified character.
static booleancontainsArabic(AttributedString as)
Returns true if the string contains any arabic characters.
static booleancontainsArabic(AttributedCharacterIterator aci)
Returns true if the ACI contains any arabic characters.
static StringcreateSubstituteString(AttributedCharacterIterator aci)
Where possible substitues plain arabic glyphs with their shaped forms.
static intgetNumChars(char c)
Returns the number of characters the glyph for the specified character represents.
static intgetSubstituteChar(char ch1, char ch2, int form)
Will try and find a substitute character of the specified form.
static intgetSubstituteChar(char ch, int form)
static booleanhasSubstitute(char ch1, char ch2)
static booleanisLigature(char c)
Returns true if the glyph for the specified character respresents a ligature.

Method Detail

arabicChar

public static boolean arabicChar(char c)
Returns true if the char is a standard arabic char. (ie. within the range U+0600 - U+6FF)

Parameters: c The character to test.

Returns: True if the char is arabic, false otherwise.

arabicCharTransparent

public static boolean arabicCharTransparent(char c)
Returns true if the char is transparent.

Parameters: c The character to test.

Returns: True if the character is transparent, false otherwise.

assignArabicForms

public static AttributedString assignArabicForms(AttributedString as)
If the AttributedString contains any arabic chars, assigns an arabic form attribute, i.e. initial|medial|terminal|isolated, to each arabic char.

Parameters: as The string to attach the arabic form attributes to.

Returns: An attributed string with arabic form attributes.

charStartsLigature

public static boolean charStartsLigature(char c)
Returns true if a ligature exists that starts with the specified character.

Parameters: c The character to test.

Returns: True if there is a ligature that starts with c, false otherwise.

containsArabic

public static boolean containsArabic(AttributedString as)
Returns true if the string contains any arabic characters.

Parameters: as The string to test.

Returns: True if at least one char is arabic, false otherwise.

containsArabic

public static boolean containsArabic(AttributedCharacterIterator aci)
Returns true if the ACI contains any arabic characters.

Parameters: aci The AttributedCharacterIterator to test.

Returns: True if at least one char is arabic, false otherwise.

createSubstituteString

public static String createSubstituteString(AttributedCharacterIterator aci)
Where possible substitues plain arabic glyphs with their shaped forms. This is needed when the arabic text is rendered using an AWT font. Simple arabic ligatures will also be recognised and replaced by a single character so the length of the resulting string may be shorter than the number of characters in the aci.

Parameters: aci Contains the text to process. Arabic form attributes should already be assigned to each arabic character.

Returns: A String containing the shaped versions of the arabic characters

getNumChars

public static int getNumChars(char c)
Returns the number of characters the glyph for the specified character represents. If the glyph represents a ligature this will be 2, otherwise 1.

Parameters: c The character to test.

Returns: The number of characters the glyph for c represents.

getSubstituteChar

public static int getSubstituteChar(char ch1, char ch2, int form)
Will try and find a substitute character of the specified form.

Parameters: ch1 The first character of two to replace. ch2 The second character of two to replace. form Indicates the required arabic form. (isolated = 1, final = 2, initial = 3, medial = 4)

Returns: The unicode value of the substutute char, or -1 if no substitute exists.

getSubstituteChar

public static int getSubstituteChar(char ch, int form)

hasSubstitute

public static boolean hasSubstitute(char ch1, char ch2)

isLigature

public static boolean isLigature(char c)
Returns true if the glyph for the specified character respresents a ligature.

Parameters: c The character to test.

Returns: True if c is a ligature, false otherwise.

Copyright B) 2007 Apache Software Foundation. All Rights Reserved.