uk.ac.open.crc.mdsc

Class Dictionary

java.lang.Object

uk.ac.open.crc.mdsc.Dictionary

public class Dictionary
extends java.lang.Object

Represents a single spelling dictionary. To understand the creation and management of these objects refer to the DictionaryManager class.

NB: this class wraps an instance of HashedSpellingDictionary and is constrained by the contracts of that class. The main issue to be aware of is the way that words are compared with those stored in the dictionary. The word being tested is compared with the words in the dictionary capitalised as it is provided to the function, and then compared again after being normalised to lower case if there is no match. The words in the dictionary are not normalised. In other words, the word being tested is tested first case sensitive, then case insensitive, but the capitalisation of the reference word remains constant. Consequently, proper nouns are only marked as correct when their capitalisation matches that used in the dictionary. This is the expected behaviour of a spell checker, but might not always be what is wanted by the user of this class. The class NormalisedDictionaryManager implements a dictionary that matches strings regardless of case, either in the dictionary or the string being tested.

Method Summary

Modifier and Type	Method and Description
Result	checkSpelling(java.lang.String word) Checks the spelling of a word in this dictionary.
Result	checkSpelling(java.lang.String word, int costThreshold) Checks the spelling of a word in this dictionary.
java.lang.String	description() Retrieves the description.
java.lang.String	name() Retrieves the dictionary's name.

Methods inherited from class java.lang.Object

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

Method Detail

name

public final java.lang.String name()

Retrieves the dictionary's name. The name is used as a tag to identify the dictionary internally.

Returns:

a String containing the dictionary's name.

description

public final java.lang.String description()

Retrieves the description. The description is intended to be human readable and should be a succinct description of the dictionary.

Returns:

a String containing the description of the dictionary

checkSpelling

public Result checkSpelling(java.lang.String word,
                            int costThreshold)

Checks the spelling of a word in this dictionary. Allows the caller to specify a cost threshold that is different to the value set in the constructor. Costs are calculated using three digits where 100 is the equivalent of 1 in conventional understanding of the Levenshtein distance. The authors of Jazzy specify a number of values for individual transformations that mostly range from 90-100, but also include include a cost of 10 for changing case. See the uk.ac.open.crc.mdsc.engine package.

NB The threshold value does not currently work as described. The threshold set in the constructor is used, and the value passed is ignored. There are two reasons: (1) this mechanism was not implemented in the underlying Jazzy engine classes, and (2) the constructor set threshold seems adequate, so any fix is low-priority.

Parameters:

word - a word to be tested

costThreshold - the maximum cost of any suggested alternative spelling

Returns:

an instance of Result containing the results of the test including a list of any alternative spellings.

checkSpelling

public Result checkSpelling(java.lang.String word)

Checks the spelling of a word in this dictionary. Uses the maximum cost value supplied to the constructor.

Parameters:

word - a word to be tested

Returns:

an instance of Result containing the results of the test including a list of any alternative spellings.