Program To Create a Snake and Ladder Game in Java Assignment Solution.

Instructions

Objective

Write a program to create a snake and ladder game in java.

Requirements and Specifications

Create an application to simulate the game of snake and ladder.

Rules of the game

The game is played on a board with numbered, gridded squares. In an example illustrated above, the board has 36 positions in total, and a few ladders and snakes that will be explained later.
Two or more players will play the game. Each player starts from position 0
Each player takes turns rolling a single die to move their token by the number of squares indicated by the die roll.

A random number from 1 to 6 is generated by a dice. If the dice is 5 and one player is at position 10, the player will move to position 15 (10 + 5)

A player wins if it exactly reaches the end position (aka position 36 in the example above) and the game ends.

If a player is supposed to move outside the board, for example dice is 5 and the player is at position 34, the player will stay at current position 34 because 34 + 5 > 36.

About Ladder: when a player ends up at a position of the start of one ladder, the player will move to the position of the end of the ladder. E.g. moving from position 3 to 16.
About Snake: when a player ends up at a position of the head of one snake, the player will move to the position of the tail of the snake. E.g. moving from position 30 to 4.
There could be another snake or ladder at the end position of the ladder or snake, and then the player will have to move up or down accordingly again.

Constraints and Validations

The application should consider the following constraints:

No snake head at the end position
No multiple snakes or ladders have same head position
Snakes and ladders should not form an infinite loop
Snake should have its tail at a smaller number than its head
Ladder should have its end position at a larger number than its start position

Logging

The application should be able to print the following messages, either to console or to file

Print every movement of each player in the following format.

Format: <player name> rolled a <dice value> and moved from <initial position> to <final position>

When someone wins the game, print that the player won the game.

Format: <player name> wins the game

Source Code

import logic.*;
import java.util.Locale;
import java.util.Scanner;
public class Driver {
 /**
  * Plays a text-based game
  */
 public static void main(String[] args) {
  try(Scanner scanner = new Scanner(System.in)) {
   GameBuilder gameBuilder = new GameBuilder();
   while (true) {
    try {
     gameBuilder = gameBuilder.boardSize(readIntChoice(scanner, "Please, enter board size: "));
     break;
    } catch (GameConfigurationException e) {
     System.out.println(e.getMessage());
    }
   }
   System.out.println();
   while (true) {
    try {
     gameBuilder = gameBuilder.playersNum(readIntChoice(scanner, "Please, enter number of players: "));
     break;
    } catch (GameConfigurationException e) {
     System.out.println(e.getMessage());
    }
   }
   System.out.println();
   while(readBoolChoice(scanner, "Do you want to add ladder? (y/n): ")) {
    try {
     int head = readIntChoice(scanner, "Please, enter ladder head: ");
     int tail = readIntChoice(scanner, "Please, enter ladder tail: ");
     gameBuilder = gameBuilder.ladder(new Ladder(head, tail));
     System.out.println("Ladder added successfully");
    }
    catch (GameConfigurationException e) {
     System.out.println(e.getMessage());
    }
    System.out.println();
   }
   while(readBoolChoice(scanner, "Do you want to add snake? (y/n): ")) {
    try {
     int head = readIntChoice(scanner, "Please, enter snake head: ");
     int tail = readIntChoice(scanner, "Please, enter snake tail: ");
     gameBuilder = gameBuilder.snake(new Snake(head, tail));
     System.out.println("Snake added successfully");
    }
    catch (GameConfigurationException e) {
     System.out.println(e.getMessage());
    }
    System.out.println();
   }
   System.out.println("Starting the game:");
   Game game = gameBuilder.build();
   while(!game.isOver()) {
    System.out.print("Please, hit 'Enter' to roll the die: ");
    scanner.nextLine();
    game.makeMove();
   }
  }
 }
 private static int readIntChoice(Scanner scanner, String prompt) {
  while(true) {
   try {
    System.out.print(prompt);
    return Integer.parseInt(scanner.nextLine());
   }
   catch (NumberFormatException e) {
    System.out.println("Invalid input");
   }
  }
 }
 private static boolean readBoolChoice(Scanner scanner, String prompt) {
  while(true) {
   System.out.print(prompt);
   String input = scanner.nextLine().trim().toLowerCase();
   if (input.equals("y")) {
    return true;
   }
   if (input.equals("n")) {
    return false;
   }
   System.out.println("Invalid input");
  }
 }
}
GAME
package logic;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Random;
public class Game {
 private final int length;
 private final Collection<Action> actions;
 private final IDie die;
 private final Player[] players;
 private int playerToMove;
 private Player winner;
 /**
  * Creates a square game board.
  *
  * @param length the width and height.
  */
 Game(int length, int playersNum, Collection<Action> actions, IDie die) {
  this.length = length;
  this.actions = new ArrayList<>(actions);
  this.die = die;
  this.players = new Player[playersNum];
  for (int i = 0; i < playersNum; i++) {
   players[i] = new Player(i + 1);
  }
  this.winner = null;
  this.playerToMove = 0;
 }
 /**
  * The size of the current game.
  *
  * @return this is both the width and the height.
  */
 public int getLength() {
  return length;
 }
 public void makeMove() {
  makeMove(playerToMove);
  playerToMove = (playerToMove + 1) % players.length;
 }
 public void makeMove(int currPlayer) {
  Player player = players[currPlayer];
  int dieScore = die.rollDie();
  int currPosition = player.getPosition();
  int nextPosition = (currPosition + dieScore > length) ? currPosition : currPosition + dieScore;
  while(true) {
   int nextPositionTmp = nextPosition;
   Action action = actions.stream().filter(a -> a.getHeadIndex() == nextPositionTmp).findAny().orElse(null);
   if (action == null) {
    break;
   }
   nextPosition = action.getTailIndex();
  }
  player.updatePosition(nextPosition);
  logMove(player, dieScore, currPosition, nextPosition);
  if (nextPosition == length) {
   winner = player;
   logWinner(player);
  }
 }
 private void logMove(Player player, int die, int from, int to) {
  System.out.printf("%s rolled a %d and moved from %d to %d%n", "Player " + player.getId(), die, from, to);
 }
 private void logWinner(Player player) {
  System.out.printf("%s wins the game%n", "Player " + player.getId());
 }
 public boolean isOver() {
  return winner != null;
 }
}
LADDER
package logic;
public class Ladder extends Action {
 public Ladder(int headIndex, int tailIndex) throws GameConfigurationException {
  super(headIndex, tailIndex);
  if (headIndex >= tailIndex) {
   throw new GameConfigurationException("Ladder has tail at a smaller number, than its head");
  }
 }
 @Override
 public String toString() {
  return "Ladder{head=" + getHeadIndex() + " tail=" + getTailIndex() + "}";
 }
}

Create A Snake and Ladder Game in Java Assignment Solution.

Instructions

Requirements and Specifications