Class Corrector

java.lang.Object

Corrector

Direct Known Subclasses:

FileCorrector, Levenshtein, SwapCorrector

public abstract class Corrector
extends java.lang.Object

Skeleton implementation for classes capable of providing spelling corrections.

The matchCase method is code that is shared among all Correctors.

Concrete subclasses of this abstract class must implement the getCorrections method (which will usually call matchCase).

Constructor Summary

Constructors

Constructor and Description
Corrector()

Method Summary

Methods

Modifier and Type	Method and Description
abstract java.util.Set<java.lang.String>	getCorrections(java.lang.String wrong) Returns a set of proposed corrections for an incorrectly spelled word.
java.util.Set<java.lang.String>	matchCase(java.lang.String incorrectWord, java.util.Set<java.lang.String> corrections) Returns a new set that contains the same words as the argued set but with the case matching that of the argued misspelled word (either all lowercase or first letter uppercase).

Methods inherited from class java.lang.Object

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

Constructor Detail

Corrector

public Corrector()

Method Detail

matchCase

public java.util.Set<java.lang.String> matchCase(java.lang.String incorrectWord,
                                        java.util.Set<java.lang.String> corrections)

Returns a new set that contains the same words as the argued set but with the case matching that of the argued misspelled word (either all lowercase or first letter uppercase). The case to match is determined by the first letter of the misspelled word. Examples:

• matchCase("Wrng", { "wrong" }) returns { "Wrong" }
• matchCase("wRng", { "wrong" }) returns { "wrong" }
• matchCase("WRNG", { "wrong" }) returns { "Wrong" }
• matchCase("wrng", { "wrong" }) returns { "wrong" }

Parameters:

incorrectWord - The word whose case should be matched

corrections - The set whose case should be fixed

Returns:

Set of corrections with case appropriately modified

Throws:

java.lang.IllegalArgumentException - If either argument is null

getCorrections

public abstract java.util.Set<java.lang.String> getCorrections(java.lang.String wrong)

Returns a set of proposed corrections for an incorrectly spelled word. The corrections should match the case of the input; the matchCase method is helpful here.

For any input that is *not* a valid word, throw an IllegalArgumentException. A valid word is any sequence of letters (as determined by Character.isLetter) or apostrophes characters.

Parameters:

wrong - The misspelled word

Returns:

A (potentially empty) set of proposed corrections

Throws:

java.lang.IllegalArgumentException - If the input is not a valid word (i.e. not composed of only letters and/or apostrophes)