Purposes of this assignment

• To get you to install some necessary software
• To give you some initial familiarity with Scala

Part I (10 points)

Translate the following Scala program into Java.

import scala.io.StdIn.readLine

object Buzzer extends App {
  val n = readLine("How high shall I count? ") toInt

  for (i <- 1 to n)
    if (i % 7 == 0 || i.toString.contains('7')) println( "buzz")
    else println(i)
}

Part II (80 points)

General idea

The computer chooses a secret 5-letter word with no repeated letters. The user then guesses 5-letter words (again, with no repeated letters). For each word guessed, the computer tells the user how many letters in the guessed word are also in the secret word, but gives no information about where they are in the secret word. Play continues until the user guesses the secret word, or gives up.

Optional: The computer should give the user help by keeping track of which letters have been proven to be in, or not in, the secret word.

For a nice version of this program, see http://jotto.augiehill.com/single.jsp. Your version will be simpler (text only instead of GUI, no choices like easy/hard or word length, etc.), but should essentially behave the same way.

Files and programming hints

Download and save the word list at http://www-01.sil.org/linguistics/wordlists/english/wordlist/wordsEn.txt.

When your program starts, it should read in this word list, discarding all words that are not exactly five letters long, or that have repeated letters. Words containing an apostrophe or other non-letters should also be discarded. Hint: Use the filter method, possibly more than once.

My Concise Introduction to Scala provides a simple way to read in a file as a list of Strings.

The Random class is in scala.util. See the Scala API for details.

Details

You should have a project named Jotto, containing a package named jotto in the src folder, containing files Jotto.scala and JottoTest.scala. The program in Jotto.scala should consist of a single object, object Jotto {...}, containing a main(args: Array[String]) method.

The program should:

• Reject guesses from the user that are not legal guesses.
• Allow the user to enter "Give up" (this should reveal the secret word).
• Be case-insensitive (you can just lowercase or uppercase all input).
• After each guess, provide the user with the following:
• A list of all the words guessed so far, each with letter counts.
• [Optional] Three lists of letters
• Letters that can be proven to be in the secret word
• Letters that can be proven to not occur in the secret word.
• Letters not in one of the above two lists.
• A congratulatory message if/when the user guesses the word.
• At the end of the program, the number of legal guesses made.

To facilitate our unit testing, please provide the following methods inside object Jotto:

def hasProperForm(word: String): Boolean

Tests whether the "word" consists of exactly five letters, all distinct.

isLegalWord(word: String): Boolean

Tests whether the word occurs in the program's list of legal words.

countMatchingLetters(word1: String, word2: String): Int

Determines how many letters the two words have in common.

provenLetters(secretWord: String, words: List[String]): Set[Char]

Determines which letters must be in the secret word, based on the words guessed so far.

disprovenLetters(secretWord: String, words: List[String]): Set[Char]

Determines which letters must not be in the secret word, based on the words guessed so far.

Unit testing (10 points)

Write, in a file JottoTest.scala , unit tests for all your non-I/O methods.

In Eclipse, go to Project → Properties → Java Build Path → Add External JARs and select your ScalaTest jar. Here is a model for your test file.

package fractionTest

import org.scalatest.FunSuite
import Fraction._

class ExampleTests extends FunSuite {
  
  val f1 = Fraction(1, 2)
  val f2 = Fraction(1, 4)
  
  test("Test multiplication") {
    assert(f1 * f1 == f2)
  }
  
  test("Test bad multiplication") {
    assert(f1 * f2 === f2) // "===" may be used in unit tests
  }
}

Due date

Zip your Java project and your Scala project together, and turn the zip file in to Canvas. Due by 11:59pm Wednesday, November 9.