Package org.apache.lucene.analysis.compound.hyphenation

Class HyphenationTree

java.lang.Object

org.apache.lucene.analysis.compound.hyphenation.TernaryTree

org.apache.lucene.analysis.compound.hyphenation.HyphenationTree

All Implemented Interfaces:

Cloneable, PatternConsumer

public class HyphenationTree
extends TernaryTree
implements PatternConsumer

This tree structure stores the hyphenation patterns in an efficient way for fast lookup. It provides the provides the method to hyphenate a word. This class has been taken from the Apache FOP project (http://xmlgraphics.apache.org/fop/). They have been slightly modified.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.analysis.compound.hyphenation.TernaryTree

TernaryTree.Iterator

Constructor Summary

Constructors

Constructor	Description
HyphenationTree()

Method Summary

Modifier and Type	Method	Description
void	addClass(String chargroup)	Add a character class to the tree.
void	addException(String word, ArrayList<Object> hyphenatedword)	Add an exception to the tree.
void	addPattern(String pattern, String ivalue)	Add a pattern to the tree.
String	findPattern(String pat)
Hyphenation	hyphenate(char[] w, int offset, int len, int remainCharCount, int pushCharCount)	Hyphenate word and return an array of hyphenation points.
Hyphenation	hyphenate(String word, int remainCharCount, int pushCharCount)	Hyphenate word and return a Hyphenation object.
void	loadPatterns(File f)	Read hyphenation patterns from an XML file.
void	loadPatterns(InputSource source)	Read hyphenation patterns from an XML file.
void	printStats(PrintStream out)

Methods inherited from class org.apache.lucene.analysis.compound.hyphenation.TernaryTree

balance, clone, find, find, insert, insert, keys, knows, size, strcmp, strcmp, strcpy, strlen, strlen, trimToSize

Methods inherited from class java.lang.Object

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

Constructor Details

HyphenationTree

public HyphenationTree()

Method Details

loadPatterns

public void loadPatterns(File f)
                  throws IOException

Read hyphenation patterns from an XML file.

Parameters:

f - the filename

Throws:

IOException - In case the parsing fails

loadPatterns

public void loadPatterns(InputSource source)
                  throws IOException

Read hyphenation patterns from an XML file.

Parameters:

source - the InputSource for the file

Throws:

IOException - In case the parsing fails

findPattern

public String findPattern(String pat)

hyphenate

public Hyphenation hyphenate(String word,
 int remainCharCount,
 int pushCharCount)

Hyphenate word and return a Hyphenation object.

Parameters:

word - the word to be hyphenated

remainCharCount - Minimum number of characters allowed before the hyphenation point.

pushCharCount - Minimum number of characters allowed after the hyphenation point.

Returns:

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.

Parameters:

w - char array that contains the word

offset - Offset to first character in word

len - Length of word

remainCharCount - Minimum number of characters allowed before the hyphenation point.

pushCharCount - Minimum number of characters allowed after the hyphenation point.

Returns:

a Hyphenation object representing the hyphenated word or null if word is not hyphenated.

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.

Specified by:

addClass in interface PatternConsumer

Parameters:

chargroup - character group

addException

public void addException(String word,
 ArrayList<Object> hyphenatedword)

Add an exception to the tree. It is used by PatternParser class as callback to store the hyphenation exceptions.

Specified by:

addException in interface PatternConsumer

Parameters:

word - normalized word

hyphenatedword - 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.

Specified by:

addPattern in interface PatternConsumer

Parameters:

pattern - the hyphenation pattern

ivalue - 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').

printStats

public void printStats(PrintStream out)

Overrides:

printStats in class TernaryTree