org.apache.commons.codec.language
Class Metaphone

java.lang.Object
  org.apache.commons.codec.language.Metaphone

All 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.

Methods inherited from class java.lang.Object

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

Field Detail

vowels

private String vowels

Five values in the English language

frontv

private String frontv

Variable used in Metaphone algorithm

varson

private String varson

Variable used in Metaphone algorithm

maxCodeLen

private int maxCodeLen

The max code length for metaphone is 4

Constructor Detail

Metaphone

public Metaphone()

Creates an instance of the Metaphone encoder

Method Detail

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

isVowel

private boolean isVowel(StringBuffer string,
                        int index)

isPreviousChar

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

isNextChar

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

regionMatch

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

isLastChar

private boolean isLastChar(int wdsz,
                           int n)

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

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.

getMaxCodeLen

public int getMaxCodeLen()

Returns the maxCodeLen.

Returns:

int

setMaxCodeLen

public void setMaxCodeLen(int maxCodeLen)

Sets the maxCodeLen.

Parameters:

maxCodeLen - The maxCodeLen to set