org.apache.commons.codec.language

Class Metaphone

Implemented Interfaces:
Encoder, StringEncoder

public class Metaphone
extends Object
implements StringEncoder

Encodes a string into a metaphone value.

Initial Java implementation by William B. Brogden. December, 1997. Permission given by wbrogden for code to be used anywhere.

Hanging on the Metaphone by Lawrence Philips in Computer Language of Dec. 1990, p 39.

Version:
$Id: Metaphone.java,v 1.20 2004/06/05 18:32:04 ggregory Exp $
Author:
Apache Software Foundation

Field Summary

private String
frontv
Variable used in Metaphone algorithm
private int
maxCodeLen
The max code length for metaphone is 4
private String
varson
Variable used in Metaphone algorithm
private String
vowels
Five values in the English language

Constructor Summary

Metaphone()
Creates an instance of the Metaphone encoder

Method Summary

Object
encode(Object pObject)
Encodes an Object using the metaphone algorithm.
String
encode(String pString)
Encodes a String using the Metaphone algorithm.
int
getMaxCodeLen()
Returns the maxCodeLen.
private boolean
isLastChar(int wdsz, int n)
boolean
isMetaphoneEqual(String str1, String str2)
Tests is the metaphones of two strings are identical.
private boolean
isNextChar(StringBuffer string, int index, char c)
private boolean
isPreviousChar(StringBuffer string, int index, char c)
private boolean
isVowel(StringBuffer string, int index)
String
metaphone(String txt)
Find the metaphone value of a String.
private boolean
regionMatch(StringBuffer string, int index, String test)
void
setMaxCodeLen(int maxCodeLen)
Sets the maxCodeLen.

Field Details

frontv

private String frontv
Variable used in Metaphone algorithm

maxCodeLen

private int maxCodeLen
The max code length for metaphone is 4

varson

private String varson
Variable used in Metaphone algorithm

vowels

private String vowels
Five values in the English language

Constructor Details

Metaphone

public Metaphone()
Creates an instance of the Metaphone encoder

Method Details

encode

public Object encode(Object pObject)
            throws EncoderException
Encodes an Object using the metaphone algorithm. This method is provided in order to satisfy the requirements of the Encoder interface, and will throw an EncoderException if the supplied object is not of type java.lang.String.
Specified by:
encode in interface Encoder
Parameters:
pObject - Object to encode
Returns:
An object (or type java.lang.String) containing the metaphone code which corresponds to the String supplied.
Throws:
EncoderException - if the parameter supplied is not of type java.lang.String

encode

public String encode(String pString)
Encodes a String using the Metaphone algorithm.
Specified by:
encode in interface StringEncoder
Parameters:
pString - String object to encode
Returns:
The metaphone code corresponding to the String supplied

getMaxCodeLen

public int getMaxCodeLen()
Returns the maxCodeLen.
Returns:
int

isLastChar

private boolean isLastChar(int wdsz,
                           int n)

isMetaphoneEqual

public boolean isMetaphoneEqual(String str1,
                                String str2)
Tests is the metaphones of two strings are identical.
Parameters:
str1 - First of two strings to compare
str2 - Second of two strings to compare
Returns:
true if the metaphones of these strings are identical, false otherwise.

isNextChar

private boolean isNextChar(StringBuffer string,
                           int index,
                           char c)

isPreviousChar

private boolean isPreviousChar(StringBuffer string,
                               int index,
                               char c)

isVowel

private boolean isVowel(StringBuffer string,
                        int index)

metaphone

public String metaphone(String txt)
Find the metaphone value of a String. This is similar to the soundex algorithm, but better at finding similar sounding words. All input is converted to upper case. Limitations: Input format is expected to be a single ASCII word with only characters in the A - Z range, no punctuation or numbers.
Parameters:
txt - String to find the metaphone code for
Returns:
A metaphone code corresponding to the String supplied

regionMatch

private boolean regionMatch(StringBuffer string,
                            int index,
                            String test)

setMaxCodeLen

public void setMaxCodeLen(int maxCodeLen)
Sets the maxCodeLen.
Parameters:
maxCodeLen - The maxCodeLen to set

commons-codec version 1.3 - Copyright © 2002-2004 - Apache Software Foundation