org.apache.fop.hyphenation
Class HyphenationTree
- Cloneable, PatternConsumer, Serializable
public class HyphenationTree
This tree structure stores the hyphenation patterns in an efficient
way for fast lookup. It provides the provides the method to
hyphenate a word.
void | addClass(String chargroup) - Add a character class to the tree.
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void | addException(String word, ArrayList hyphenatedword) - Add an exception to the tree.
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void | addPattern(String pattern, String ivalue) - Add a pattern to the tree.
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String | findPattern(String pat)
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protected byte[] | getValues(int k)
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protected int | hstrcmp(char[] s, int si, char[] t, int ti) - String compare, returns 0 if equal or
t is a substring of s
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Hyphenation | hyphenate(String word, int remainCharCount, int pushCharCount) - Hyphenate word and return a Hyphenation object.
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Hyphenation | hyphenate(char[] w, int offset, int len, int remainCharCount, int pushCharCount) - Hyphenate word and return an array of hyphenation points.
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void | loadPatterns(InputSource source) - Read hyphenation patterns from an XML file.
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void | loadPatterns(String filename) - Read hyphenation patterns from an XML file.
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static void | main(String[] argv)
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protected int | packValues(String values) - Packs the values by storing them in 4 bits, two values into a byte
Values range is from 0 to 9.
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void | printStats()
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protected void | searchPatterns(char[] word, int index, byte[] il) - Search for all possible partial matches of word starting
at index an update interletter values.
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protected String | unpackValues(int k)
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balance , clone , find , find , init , insert , insert , insertBalanced , keys , knows , main , printStats , size , strcmp , strcmp , strcpy , strlen , strlen , trimToSize |
classmap
protected TernaryTree classmap
This map stores the character classes
stoplist
protected HashMap stoplist
This map stores hyphenation exceptions
vspace
protected ByteVector vspace
value space: stores the interletter values
HyphenationTree
public HyphenationTree()
addClass
public void addClass(String chargroup)
Add a character class to the tree. It is used by
PatternParser
as callback to
add character classes. Character classes define the
valid word characters for hyphenation. If a word contains
a character not defined in any of the classes, it is not hyphenated.
It also defines a way to normalize the characters in order
to compare them with the stored patterns. Usually pattern
files use only lower case characters, in this case a class
for letter 'a', for example, should be defined as "aA", the first
character being the normalization char.
- addClass in interface PatternConsumer
addException
public void addException(String word,
ArrayList hyphenatedword)
Add an exception to the tree. It is used by
PatternParser
class as callback to
store the hyphenation exceptions.
- addException in interface PatternConsumer
word
- normalized wordhyphenatedword
- a vector of alternating strings and
hyphen
objects.
addPattern
public void addPattern(String pattern,
String ivalue)
Add a pattern to the tree. Mainly, to be used by
PatternParser
class as callback to
add a pattern to the tree.
- addPattern in interface PatternConsumer
pattern
- the hyphenation patternivalue
- interletter weight values indicating the
desirability and priority of hyphenating at a given point
within the pattern. It should contain only digit characters.
(i.e. '0' to '9').
findPattern
public String findPattern(String pat)
getValues
protected byte[] getValues(int k)
hstrcmp
protected int hstrcmp(char[] s,
int si,
char[] t,
int ti)
String compare, returns 0 if equal or
t is a substring of s
hyphenate
public Hyphenation hyphenate(String word,
int remainCharCount,
int pushCharCount)
Hyphenate word and return a Hyphenation object.
word
- the word to be hyphenatedremainCharCount
- Minimum number of characters allowed
before the hyphenation point.pushCharCount
- Minimum number of characters allowed after
the hyphenation point.
- a
Hyphenation
object representing
the hyphenated word or null if word is not hyphenated.
hyphenate
public Hyphenation hyphenate(char[] w,
int offset,
int len,
int remainCharCount,
int pushCharCount)
Hyphenate word and return an array of hyphenation points.
w
- char array that contains the wordoffset
- Offset to first character in wordlen
- Length of wordremainCharCount
- Minimum number of characters allowed
before the hyphenation point.pushCharCount
- Minimum number of characters allowed after
the hyphenation point.
- a
Hyphenation
object representing
the hyphenated word or null if word is not hyphenated.
loadPatterns
public void loadPatterns(InputSource source)
throws HyphenationException
Read hyphenation patterns from an XML file.
source
- the InputSource for the file
loadPatterns
public void loadPatterns(String filename)
throws HyphenationException
Read hyphenation patterns from an XML file.
main
public static void main(String[] argv)
throws Exception
- main in interface TernaryTree
packValues
protected int packValues(String values)
Packs the values by storing them in 4 bits, two values into a byte
Values range is from 0 to 9. We use zero as terminator,
so we'll add 1 to the value.
values
- a string of digits from '0' to '9' representing the
interletter values.
- the index into the vspace array where the packed values
are stored.
searchPatterns
protected void searchPatterns(char[] word,
int index,
byte[] il)
Search for all possible partial matches of word starting
at index an update interletter values. In other words, it
does something like:
for(i=0; i
But it is done in an efficient way since the patterns are
stored in a ternary tree. In fact, this is the whole purpose
of having the tree: doing this search without having to test
every single pattern. The number of patterns for languages
such as English range from 4000 to 10000. Thus, doing thousands
of string comparisons for each word to hyphenate would be
really slow without the tree. The tradeoff is memory, but
using a ternary tree instead of a trie, almost halves the
the memory used by Lout or TeX. It's also faster than using
a hash table
word
- null terminated word to matchindex
- start index from wordil
- interletter values array to update
unpackValues
protected String unpackValues(int k)
Copyright 1999-2008 The Apache Software Foundation. All Rights Reserved.