uk.ac.open.crc.mdsc.engine

Class DoubleMetaphoneTransformator

java.lang.Object

uk.ac.open.crc.mdsc.engine.DoubleMetaphoneTransformator

All Implemented Interfaces:

Transformator

public class DoubleMetaphoneTransformator
extends java.lang.Object
implements Transformator

A phonetic encoding algorithm that takes an English word and computes a phonetic version of it. This allows for phonetic matches in a spell checker. This class is a port of the C++ DoubleMetaphone() class, which was intended to return two possible phonetic translations for certain words, although the Java version only seems to be concerned with one, making the "double" part erroneous.

Source code for the original C++ can be found here: http://aspell.sourceforge.net/metaphone/ DoubleMetaphone does some processing, such as uppercasing, on the input string first to normalize it. Then, to create the key, the function traverses the input string in a while loop, sending successive characters into a giant switch statement. Before determining the appropriate pronunciation, the algorithm considers the context surrounding each character within the input string.

Constructor Summary

Constructors

Constructor and Description
DoubleMetaphoneTransformator()

Method Summary

Modifier and Type	Method and Description
char[]	getReplaceList() gets the list of characters that should be swapped in to the misspelled word in order to try to find more suggestions.
java.lang.String	transform(java.lang.String word) Take the given word, and return the best phonetic hash for it.

Methods inherited from class java.lang.Object

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

Constructor Detail

DoubleMetaphoneTransformator

public DoubleMetaphoneTransformator()

Method Detail

transform

public final java.lang.String transform(java.lang.String word)

Take the given word, and return the best phonetic hash for it. Vowels are minimized as much as possible, and consonants that have similiar sounds are converted to the same consonant for example, 'v' and 'f' are both converted to 'f'

Specified by:

transform in interface Transformator

Parameters:

word - the text to transform

Returns:

the result of the phonetic transformation

getReplaceList

public char[] getReplaceList()

Description copied from interface: Transformator

gets the list of characters that should be swapped in to the misspelled word in order to try to find more suggestions. In general, this list represents all of the unique phonetic characters for this Transformator.

The replace list is used in the getSuggestions method. All of the letters in the misspelled word are replaced with the characters from this list to try and generate more suggestions, which implies l*n tries, if l is the size of the string, and n is the size of this list.

In addition to that, each of these letters is added to the misspelled word.

Specified by:

getReplaceList in interface Transformator

Returns:

an array of replacement characters

See Also:

Transformator.getReplaceList()