Required Skills Inventory

Declare and instantiate an ArrayList

Write a method according to given specifications

Write a method that returns an ArrayList

Write a method that takes an ArrayList as an argument

Open and read input from a text file

Use a Scanner to read input from a text file

Use String methods to identify and compare specific character in a String

Implement a simple linear search over a collection

Compose a program out of simple methods

Problem Description

For this project you will construct a program that will search a list for words that match a specified pattern. For example, given the following list of words:

amble

apple

box

echoes

fox

school

tumble

and the pattern:

$\_$cho$\_\_$

the program will find and print out:

$[$echoes$,$ school$]$

Note that the only words in the list of seven words above that match the pattern $\_$cho$\_\_$ are echoes and school. These two words match the pattern because the pattern specifies a six letter word that has the letters c$,$ h$,$ and o as the second, third, and fourth letters. In the pattern, an underscore $(\_)$ specifies any single letter.

$\_$ c h o $\_\_$

e c h o e s

s c h o o l

The project can be broken down into the following methods:

getWordList$($String$)$ : ArrayList The purpose of this public static method is to open a text file containing a list of words and return an ArrayList that contains all the words in the file. This method should be defined to throw a FileNotFoundException using the throws keyword. Later, this ArrayList will be searched to find words that match a specified pattern.

When called and passed a file name $($like "words.txt$"),$ this method will declare and instantiate a new ArrayList, then open the specified text file. The method will then read in each word in the file and add each word to the ArrayList. After all words have been read and added this method will return the ArrayList.

Note: The file will always contain a list of words with one word on each line, and each line ending with a newline $($

$)$ character.

Hint: The Scanner constructor method throws a FileNotFoundException when attempting to access a file.

isMatchAtIndex$($String$,$ String, int$)$ : boolean A public static method that when called and passed a word $($String$),$ and a pattern $($String$),$ and an index $($int$),$ the method will determine if the character at the index in the pattern is a match for the character at the same index in the word. The method will return true if the characters are a match, otherwise it will return false.

Example $1$

isMatchAtIndex$("$school$","\_$cho$\_\_",2)$ would return true because the character at index $2$ in the pattern $"\_$cho$\_\_"(\text{'}$h$\text{'})$ is an exact match for the character at index $2$ in the word "school".

Example $2$

isMatchAtIndex$("$school$","\_$chi$\_\_",3)$ would return false because the character at index $3$ in the pattern $"\_$chi$\_\_"(\text{'}$i$\text{'})$ is not a match for the character at index $3$ in the word "school" $(\text{'}$o$\text{'}).$

Example $3$

isMatchAtIndex$("$school$","\_$cho$\_\_",0)$ would return true because the character at index $0$ in the pattern $"\_$cho$\_\_"(\text{'}\_\text{'})$ is an underscore and an underscore is a match for any character.

Example $4$

isMatchAtIndex$("$school$","\_$cho$\_",5)$ would return false because there is no character at index $5$ in the pattern $"\_$cho$\_".$

isMatch$($String$,$ String$)$ : boolean A public static method that when called and passed a word $($String$),$ and a pattern $($String$),$ will determine if the specified word matches the specified pattern. The method will return true if the word and pattern match, otherwise it will return false.

Note that if a word does match a pattern, it is because isMatchAtIndex$($word$,$ pattern, index$)$ returns true for each index.

Example $1$

isMatch$("$school$","\_$cho$\_\_")$ would return true because all character in the pattern match the character at the same index in the word. Remember that an underscore character $(\text{'}\_\text{'})$ in the pattern matches any letter at that same index in the word.

Example $2$

isMatch$("$school$","\_$chi$\_\_")$ would return false because the character at index $3$ in the pattern $"\_$chi$\_\_"(\text{'}$i$\text{'})$ is not a match for the character at index $3$ in the word "school" $(\text{'}$o$\text{'}),$ and therefore the word "school" does not match the pattern $"\_$chi$\_\_".$

Example $3$

isMatch$("$apple$","$a$\_$p$\_")$ would return false because the word and the patter are not the same length, so they cannot be a match.

getMatches$($ArrayList$,$ String$)$ : ArrayList Write a public static method named getMatches. This method will take an ArrayList as its first argument and a String as its second argument. The method will return an Arraylist. When called and passed an word list $($ArrayList$),$ and a pattern $($String$),$ the method will find all of the words in the word list that match the specified pattern, add these to a new ArrayList, and then return this new ArrayList.

Given an ArrayList named wordList that contains the following words:

amble

apple

box

echoes

fox

school

tumble

Example $1$

getMatches$($wordList$,"\_$cho$\_\_")$ woul