Package org.egothor.stemmer

Class Trie

java.lang.Object

org.egothor.stemmer.Trie

Direct Known Subclasses:

MultiTrie

public class Trie
extends Object

A Trie is used to store a dictionary of words and their stems.

Actually, what is stored are words with their respective patch commands. A trie can be termed forward (keys read from left to right) or backward (keys read from right to left). This property will vary depending on the language for which a Trie is constructed.

Constructor Summary

Constructors

Constructor	Description
Trie(boolean forward)	Constructor for the Trie object.
Trie(boolean forward, int root, List<CharSequence> cmds, List<Row> rows)	Constructor for the Trie object.
Trie(DataInput is)	Constructor for the Trie object.

Method Summary

Modifier and Type	Method	Description
CharSequence[]	getAll(CharSequence key)	Gets the all attribute of the Trie object
int	getCells()	Return the number of cells in this Trie object.
int	getCellsPnt()	Gets the cellsPnt attribute of the Trie object
int	getCellsVal()	Gets the cellsVal attribute of the Trie object
CharSequence	getFully(CharSequence key)	Return the element that is stored in a cell associated with the given key.
CharSequence	getLastOnPath(CharSequence key)	Return the element that is stored as last on a path associated with the given key.
void	printInfo(PrintStream out, CharSequence prefix)	writes debugging info to the printstream
Trie	reduce(Reduce by)	Remove empty rows from the given Trie and return the newly reduced Trie.
void	store(DataOutput os)	Write this Trie to the given output stream.

Methods inherited from class java.lang.Object

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

Constructor Detail

Trie

public Trie(DataInput is)
     throws IOException

Constructor for the Trie object.

Parameters:

is - the input stream

Throws:

IOException - if an I/O error occurs

Trie

public Trie(boolean forward)

Constructor for the Trie object.

Parameters:

forward - set to true

Trie

public Trie(boolean forward,
            int root,
            List<CharSequence> cmds,
            List<Row> rows)

Constructor for the Trie object.

Parameters:

forward - true if read left to right, false if read right to left

root - index of the row that is the root node

cmds - the patch commands to store

rows - a Vector of Vectors. Each inner Vector is a node of this Trie

Method Detail

getAll

public CharSequence[] getAll(CharSequence key)

Gets the all attribute of the Trie object

Parameters:

key - Description of the Parameter

Returns:

The all value

getCells

public int getCells()

Return the number of cells in this Trie object.

Returns:

the number of cells

getCellsPnt

public int getCellsPnt()

Gets the cellsPnt attribute of the Trie object

Returns:

The cellsPnt value

getCellsVal

public int getCellsVal()

Gets the cellsVal attribute of the Trie object

Returns:

The cellsVal value

getFully

public CharSequence getFully(CharSequence key)

Return the element that is stored in a cell associated with the given key.

Parameters:

key - the key

Returns:

the associated element

getLastOnPath

public CharSequence getLastOnPath(CharSequence key)

Return the element that is stored as last on a path associated with the given key.

Parameters:

key - the key associated with the desired element

Returns:

the last on path element

store

public void store(DataOutput os)
           throws IOException

Write this Trie to the given output stream.

Parameters:

os - the output stream

Throws:

IOException - if an I/O error occurs

reduce

public Trie reduce(Reduce by)

Remove empty rows from the given Trie and return the newly reduced Trie.

Parameters:

by - the Trie to reduce

Returns:

the newly reduced Trie

printInfo

public void printInfo(PrintStream out,
                      CharSequence prefix)

writes debugging info to the printstream