I have read and understood the sections of plagiarism in the College Policy on assessment offences and confirm that the work is my own, with the work of others clearly acknowledged. I give my permission to submit my report to the plagiarism testing database that the College is using and test it using plagiarism detection software, search engines or meta-searching software.
This coursework takes inspiration from the board game Scrabble, although it has certain differences with the standard Scrabble game. To reduce your workload, ScraBBKle has some simplification over Scrabble, but also some generalisations. The game will be played between a Human player and a Computer player. However, the board size will be S x S, where S is an integer number between 12 and 26, instead of the usual 15 x 15. (We only set the limit 26 to avoid visualisation/printing problems for large boards.)
The rules of ScraBBKle have been inspired by the ones available here for the Scrabble game.
The goal of the game is to populate the board with a grid of tiles, similar to a crossword, so that all words on the board are from a pre-defined word list. Both players have a rack of up to 7 tiles which is refilled from a tile bag after every move. Each tile has a letter and a numerical value.
When the game is started, the user is asked whether to load a specific board from the file system or whether to use the default board. The default board corresponds to the Scrabble board.
After that, both players get 7 randomly chosen tiles from the tile bag. The human player is then shown the (currently empty) board and their own tiles. The human player plays the first move.
The columns will be designated by lower-case letter characters from a to z and the rows by numbers from 1 to 26. The leftmost column is a and the bottom row is 1.
The first move is done by the human player, by combining two or more of their letters to a word. The word is placed on the board to read either to the right or downwards, with one letter on the centre square. Like in Scrabble, diagonal words are not possible in ScraBBKle. Whenever a tile is placed on a square, the letter and the value of the tile replace the square on the board. If the value S from the intro is an even number, there are four candidates for the role of "centre square". In ScraBBKle, the top left of these four squares (i.e., the one with minimal column and row) is the centre square for the purposes of the first move.
The game computes the score resulting from the move. As long as the tile bag is not empty, the player who just made a move will have their tile rack topped up with tiles taken from the tile bag so that it has 7 tiles again.
The next move is the computer player's. From now on, the computer player and the human player take turns with their moves until one player has no more tiles on their rack or no more moves are possible.
The player whose turn it is adds one or more letters to the letters already on the board to form a new word. All letters played in a move must be placed in one row to the right or downwards and contribute to a new word. It is allowed to skip occupied positions (for example, one may extend NO to SNOW by adding a S at the beginning and at the same time a W at the end). In ScraBBKle, every move may lead to only one occurrence of a new or changed word on the board. In contrast to the original Scrabble game, it is not allowed to place a word at right angles to a word already on the board without an overlap, nor to place a complete word parallel immediately next to a word already played.
Once a tile has been used in a move, its position on the board stays unchanged.
There are special tiles, called wildcards or blanks, where the letter is initially not given, but can be chosen by the player as needed. In our game, the choice is entered as a small letter. As soon as the choice has been made for a given wildcard, it stays fixed for the rest of the game. The value of a wildcard in ScraBBKle is 3. When a wildcard has been played, its letter used for display on the board is the chosen small letter - the choice lasts for the whole game.
A player is allowed to pass the current turn (i.e., not make a move and allow the next player to continue).
In ScraBBKle, it is not allowed to exchange tiles from the tile rack with tiles from the tile bag.
Moves must always lead to words that are in the game's word list. (This is checked by the game, and invalid moves are rejected by the game.)
The game ends when the tile bag is empty and one of the player has an empty tile rack. The game also ends if both players pass twice in a row.
The score for each move is calculated as the sum of the letter values in the word created or modified in the move, plus the extra points obtained (or lost!) from tiles placed on premium squares.
Premium letter squares have an integer number of at least -9 and at most 99 as a factor (specifically, 0 or negative values are possible). When a tile is placed on a premium letter square, the score for the tile is its value multiplied by the factor of the premium letter square. A premium letter square has the shape (x) if the factor x is a single character and the shape (xy if the factor xy has two characters.
Premium word squares also have an integer number of at least -9 and at most 99 as a factor (specifically, 0 or negative values are possible). When a move places a tile on a premium word square, the factor of the premium word square will be multiplied with the score obtained for the word otherwise. If a move uses several premium letter squares, the effect is cumulative (for example, when we use a premium word square with factor 4 and a second premium word square with factor 5 in the same move, the resulting factor for the word score would be 4*5 = 20). Premium word squares are applied only after premium letter squares. A premium word square has the shape {x} if the factor x is a single character and the shape {xy if the factor xy has two characters.
A square cannot be at the same time both a premium letter square and a premium word square. There can also be squares that are not premium letter squares or premium word squares. Such squares are displayed as . (i.e., a space, then a dot, then a space).
Letter and word premium squares are applied only in a single move. As soon as they have been covered by a tile, in later moves this tile will count at its face value (i.e., the score will not be affected by the premium formerly obtained from covering the tile).
Woo-hoo! If a player manages to play all 7 tiles in one move, they are awarded an extra score of 70 points in ScraBBKle. This extra score is added only after all the other calculations for the current move are done (so also with a premium word square involved in the move, the player would still get only 70 extra score points).
At the end of the game, at least one player will have unplayed tiles. Each player's score is reduced by the sum of the values of their own unplayed tiles.
The player who has a higher score at the end of the game wins. If the scores are equal, the game is declared a draw.
For example, after starting the game, the human player may see the following board (here the default board was chosen) and tiles:
a b c d e f g h i j k l m n o
1 {3} . . (2) . . . {3} . . . (2) . . {3}
2 . {2} . . . (3) . . . (3) . . . {2} .
3 . . {2} . . . (2) . (2) . . . {2} . .
4 (2) . . {2} . . . (2) . . . {2} . . (2)
5 . . . . {2} . . . . . {2} . . . .
6 . (3) . . . (3) . . . (3) . . . (3) .
7 . . (2) . . . (2) . (2) . . . (2) . .
8 {3} . . (2) . . . {2} . . . (2) . . {3}
9 . . (2) . . . (2) . (2) . . . (2) . .
10 . (3) . . . (3) . . . (3) . . . (3) .
11 . . . . {2} . . . . . {2} . . . .
12 (2) . . {2} . . . (2) . . . {2} . . (2)
13 . . {2} . . . (2) . (2) . . . {2} . .
14 . {2} . . . (3) . . . (3) . . . {2} .
15 {3} . . (2) . . . {3} . . . (2) . . {3}
It's your turn! Your tiles:
[T1], [I1], [U1], [M3], [G2], [R1], [L1]
The human player makes the first move in ScraBBKle. The game asks the human player to enter their move by indicating the word, the position, and the direction of the word, separated by commas. In the above scenario, the human player may type
GIT,f8,r
to indicate that they want to play the word GIT, starting at position f8, and going to the right (here r means right and d means down). If a move is not possible, the game tells the human player about this (ideally with an explanation) and requests another input.
However, the move entered above is possible - the human player has the necessary tiles on the rack, the position and direction are possible as well, and one word from the word list will be created on the board.
As a result, both the scores and the board are updated and displayed:
The move is: Word: GIT at position f8, direction: right
Human player score: 8
Computer player score: 0
a b c d e f g h i j k l m n o
1 {3} . . (2) . . . {3} . . . (2) . . {3}
2 . {2} . . . (3) . . . (3) . . . {2} .
3 . . {2} . . . (2) . (2) . . . {2} . .
4 (2) . . {2} . . . (2) . . . {2} . . (2)
5 . . . . {2} . . . . . {2} . . . .
6 . (3) . . . (3) . . . (3) . . . (3) .
7 . . (2) . . . (2) . (2) . . . (2) . .
8 {3} . . (2) . G2 I1 T1 . . . (2) . . {3}
9 . . (2) . . . (2) . (2) . . . (2) . .
10 . (3) . . . (3) . . . (3) . . . (3) .
11 . . . . {2} . . . . . {2} . . . .
12 (2) . . {2} . . . (2) . . . {2} . . (2)
13 . . {2} . . . (2) . (2) . . . {2} . .
14 . {2} . . . (3) . . . (3) . . . {2} .
15 {3} . . (2) . . . {3} . . . (2) . . {3}
The human player also receives new tiles from the tile bag.
Now it is the computer player's turn. The computer player's tiles are not visible to the human player. The computer player responds with its own move, which again leads to a valid word from the word list on the board (STAR).
The move is: Word: SAR at position h7, direction: down
The result is:
Human player score: 8
Computer player score: 4
a b c d e f g h i j k l m n o
1 {3} . . (2) . . . {3} . . . (2) . . {3}
2 . {2} . . . (3) . . . (3) . . . {2} .
3 . . {2} . . . (2) . (2) . . . {2} . .
4 (2) . . {2} . . . (2) . . . {2} . . (2)
5 . . . . {2} . . . . . {2} . . . .
6 . (3) . . . (3) . . . (3) . . . (3) .
7 . . (2) . . . (2)S1 (2) . . . (2) . .
8 {3} . . (2) . G2 I1 T1 . . . (2) . . {3}
9 . . (2) . . . (2)A1 (2) . . . (2) . .
10 . (3) . . . (3) . R1 . (3) . . . (3) .
11 . . . . {2} . . . . . {2} . . . .
12 (2) . . {2} . . . (2) . . . {2} . . (2)
13 . . {2} . . . (2) . (2) . . . {2} . .
14 . {2} . . . (3) . . . (3) . . . {2} .
15 {3} . . (2) . . . {3} . . . (2) . . {3}
It's your turn! Your tiles:
[T1], [I1], [U1], [M3], [G2], [R1], [L1]
Now it is the human player's turn again to extend the crossword pattern.
The human player, who may be familiar with Scrabble, may be tempted to play
TG,g9,r
as their next move. However, doing so would lead to two words appearing on the board: TAG going to the right from position g9, and IT going down from position g8. In ScraBBKle, this is not allowed, and the game would reject the move.
In ScraBBKle, a move may never lead to more than one word of 2 or more letters being created on the board. (This is different from Scrabble.) The created word must always be in the same direction as the player's move and use all tiles of the move.
We need to define a file format for ScraBBKle boards that a user may write with a text editor. We use a plain-text format.
The first line of a file for a ScraBBKle board stores a integer number S between 12 and 26. This number indicates the size of our S x S ScraBBKle board.
After the first line, there are S further lines. Each of these lines consists of exactly S of the following "tokens", each of which represents a square:
.represents a standard square without premium.(n)represents a letter premium square, wherenis an integer between-9and99.{n}represents a word premium square, wherenis an integer between-9and99.
Note that in our file format, a premium square may need either 3 or 4 characters. Our file format does not allow for spaces.
See the file defaultBoard.txt for an example. A file is valid if it is syntactically correct as specified above.
As indicated above, you will need to read moves for the human player.
The pass move is indicated by writing a line that consists of two commas: ,,
A move to play tiles is indicated by writing the wold spelled by the tiles that are played (excluding the tiles already on the board), then a comma, then the position in format cr, then a comma, then the direction.
Here cr indicates the column and row of the "origin" of the move. For example, OND,f8,d says that from the position in column f and row 8 on the board, going down, a tile sequence corresponding to the word OND should be played, where occupied squares are skipped. Another example is VLuE,b12,r, which says that from position b12, going right, a tile sequence corresponding to the word VLUE should be played, where a wildcard should be used for the U on the board (indicated by the use of the lower-case letter u).
Note: the requirements below are mandatory to follow. You will lose marks if your implementation does not meet these requirements
In this coursework, you shall implement a Java program in which a human user shall play ScraBBKle described above against the computer. The human always makes the first move.
When the program is executed, it first prompts the user to provide a file name that stores a plain board configuration:
Would you like to _l_oad a board or use the _d_efault board?
Please enter your choice (l/d):
The user inputs l or d. Otherwise, the program states this and asks the user again for input.
If the user inputs d, the default board is loaded from the file defaultBoard.txt. If the user inputs l, the program asks for the file name:
Please enter the file name of the board:
Then the user enters the file name. If this file is not valid, the program states that and prompts to provide a file name again:
This is not a valid file. Please enter the file name of the board:
This continues until the user provides a valid file. If a valid file is provided, the board that it contains is used for the game, and the game begins.
The human player and the computer player take turns with their moves. The human player makes the first move.
Before each move, the program prints the current score and the current board.
If it is the human player's turn, the program asks the human player for their move.
Please enter your move with letter sequence, position, and
direction (d for down, r for right) separated by commas.
Entering just two commas passes.
If the entered move does not follow the above format, the program states this and asks again for input of a move:
This is not a valid move.
Please enter your move with letter sequence, position, and
direction (d for down, r for right) separated by commas.
Entering just two commas passes.
This continues until the user inputs a valid move. Then the updated board and score are displayed.
When it is the computer player's turn, the move is computed by the program based on the tiles in the computer player's tile rack and the current state of the board. The move is then printed, and the updated board and score are displayed.
If the condition for the end 917A of the game is reached (see Rules above), this is stated, the final scores of both players are calculated and shown, and the winner is announced.
Game Over!
The human player scored 216 points.
The computer player scored 203 points.
The human player wins!
(scores may vary). Instead of
The human player wins!
it may also read
The computer player wins!
or
It's a draw!
Then the program terminates.
Implement the computer player in such a way that it will always make a move with at least one tile whenever such a move is possible with the given tile rack, board state, and word list.
Hint: A possible strategy to achieve this goal could be the following:
For each number n of tiles that could be played from the current tile rack (between 1 and at most the number of tiles on the rack), for each free position on the board and for both directions, check whether it is possible to play n tiles there. (Often enough, the answer will be false, e.g., because no connection to the existing crossword on the board would be made. There is no need to check all the possible combinations of n tiles for a position and direction where they cannot be played anyway!)
For those cases of part (1) where it is indeed possible to play n tiles, go through all combinations of n tiles on your rack. If one of them leads to a valid move for the board and the word list, make the move.
Hint: Consider implementing first the other parts of the coursework project. While you are getting up and running, a computer player that always passes their move does the job.
-
The requirements below are mandatory to follow. You will lose marks if your implementation does not adhere to these requirements, even in case your program runs with no errors.
-
Your implementation shall be in Java 17.
-
The class from which the program is run shall be called
Main.javaand be in the packagepij.main. -
Your program design shall employ object-oriented principles with suitable definitions of classes/interfaces and using packages, encapsulation, polymorphism, and inheritance as appropriate for this case.
Your submission shall contain 20 (or more) JUnit 5 test cases that test the functionality of your implementation. The test cases should cover a broad range of scenarios.
Your code shall be well-structured in terms of visual readability (use indentation, spacing, etc.) and non-redundancy (instead of duplicating long pieces of code, introduce your own methods). Follow sensible naming conventions. Your code shall be well documented.
You shall accept this coursework assignment via its invitation link, which is available behind the Assessment tile of the Moodle website for the Programming in Java module. When you accept the coursework assignment, your personal GitHub repository with the initial files for the coursework assignment will be set up for you so that you can use it with your GitHub account. It is up to you whether you create a new GitHub account for this assignment or use an existing GitHub account.
You are expected to work on the coursework in your assigned GitHub repository. You must create commits, with messages, that describe the history of the development of your project. We expect at least one commit within any 14 days interval from the date of release of this coursework assignment to the date you submit your project (on Moodle). You will lose marks if you do not meet this requirement. The use of other features of git, e.g., branches, is optional and does not contribute to your mark.
Information about the release date and the submission deadline for this coursework assignment is available behind the Assessment tile of the Moodle website for the Programming in Java module.
The file README.md shall contain your name in the first section. In the second section, you shall provide the following academic declaration:
"I have read and understood the sections of plagiarism in the College Policy on assessment offences and confirm that the work is my own, with the work of others clearly acknowledged. I give my permission to submit my report to the plagiarism testing database that the College is using and test it using plagiarism detection software, search engines or meta-searching software."
This refers to the following document: College Policy on assessment offences
A submission without this declaration shall receive 0 marks.
The other sections (from "Description of the coursework: ScraBBKle" onward) shall not be modified.
Hint: Cloning your repository from GitHub to your computer, then entering your name and the academic declaration into README.md, and then committing and pushing your changes to GitHub could be a wonderful way to start your coursework assignment and check whether your git set-up works as intended.
The files of the final version of your project must be submitted via GitHub and via Moodle. We require at least the following in your submission:
README.mdwith your name and your academic declaration added in the first two sectionssrc/pij/main/Main.javaresources/defaultBoard.txtresources/wordlist.txt
and any other files or directories that are needed for the program started from class Main in package pij.main to run, as well as the JUnit tests.
Note: by the deadline of coursework submission, you must have both:
- the GitHub repo with the final version of your coursework (and history)
- the code of the project on Moodle
Both entries contribute to your mark.
You can use any standard Java libraries that are part of Java 17 in your implementation. Additionally, you will need the libraries for JUnit 5. Otherwise, no libraries are allowed.
We aim to determine your mark according to the following rubric:
| Category | Weight | full | 3/4 | 1/2 | 1/4 | 0 |
|---|---|---|---|---|---|---|
| User requirements (completeness = system responds to all use scenarios; correctness = all responses are as expected) | 40% | Correct and complete | Correct and mostly complete | Mostly correct and mostly complete | Either mostly incorrect and mostly complete, or mostly incomplete and mostly correct | Either fully incorrect, or fully incomplete, or mostly incorrect and mostly incomplete |
| Implementation requirements (completeness = a sensible design has been chosen; correctness = its implementation is correct | 30% | Correct and complete | Correct and mostly complete | Mostly correct and mostly complete | Either mostly incorrect and mostly complete, or mostly incomplete and mostly correct | Either fully incorrect, or fully incomplete, or mostly incorrect and mostly incomplete |
| Validation (completeness = appropriate variety of scenarios are verified; correctness = tests for them are correctly written) | 10% | Correct and complete | Correct and mostly complete | Mostly correct and mostly complete | Either mostly incorrect and mostly complete, or mostly incomplete and mostly correct | Either fully incorrect, or fully incomplete, or mostly incorrect and mostly incomplete |
| Development style (well-structured code = visual readability and non-redundancy (see Software Specification); commit history = commits on fortnightly basis (see Development and Submission) | 20% | Well-structured code and regular commits | Well-structured code and one gap in commits | Nearly well-structured code and at most one gap | Not well-structured code or more than one gap | Not well-structured code and more than one gap |
Note: If you do not provide commits for longer than four weeks, it counts as two gaps.
The file wordlist.txt is a slightly abridged version of the SOWPODS word list that is available for download here.