Question

import java.io.*;
import java.util.*;

/**
 *
 *
 * 
 * 
 * Lab Project 9: Rock, Paper, Scissors
 *
 * @authors *** Replace with your names here ***
 */
public class lab
{
  // global named constant for random number generator
  static Random gen = new Random();
  
  // global named constants for game choices
  static final int ROCK = 1;
  static final int PAPER = 2;
  static final int SCISSORS = 3;
  
  // global names constants for game outcomes
  static final int PLAYER1_WINS = 11;
  static final int PLAYER2_WINS = 12;
  static final int DRAW = 3;
  
  // global named constant for error condition
  static final int ERROR = -1;
  
  /**
   * 1. Get human player's choice
   * 2. Get computer player's (random) choice
   * 3. Check human player's choice
   * 4. Check computer player's choice
   * 5. Announce winner
   */
  public static void main(String[] args)
  {
    Scanner scan = new Scanner(System.in);
    PrintStream output = System.out;
    
    int player1, player2;
    
    // get player 1 input as 1 (rock), 2 (paper or 3 (scissors)
    output.print("Choose 1 (rock), 2 (paper), or 3 (scissors): ");
    player1 = scan.nextInt();
    
    /* Lab 9.1
     *
     * *** Add code here to validate that player1 has entered
     *     an integer between 1 and 3
     *     otherwise, ABORT the program
     */
    
    
    // echo human player's choice
    System.out.print(" You chose ");
    if (player1 == ROCK) { System.out.println("rock"); }
    else if (player1 == PAPER) { System.out.println("paper"); }
    else { System.out.println("scissors"); }
    
    // now computer picks one randomly
    
    output.println("Now I choose one ...");
    
    /*
     Lab 9.2
     
     *** Add code to and un-comment the following line so that
     player2 is set to a random integer between 1 and 3,
     using the gen Random object, ALREADY DECLARED AS
     A GLOBAL VARIABLE:
     */
    
    // player2 = ...;
    
    System.out.print(" I choose ");
    
    /* Lab 9.3
     *
     * *** Add code here to output the computer's choice
     *     as "rock", "paper" or "scissors"
     */
    
    
    
    /* Lab 9.4
     *
     * *** Add code below to compare player input against
     *     computer's choice and output results:
     *
     *     if human player chose ROCK:
     *       call rockChoice method with computer choice
     *       output the game's outcome (returned from rockChoice)
     *     otherwise, if human player chose PAPER:
     *       call paperChoice method with computer choice
     *       output the game's outcome (returned from paperChoice)
     *    otherwise, if human player chose SCISSORS:
     *       call scissorcChoice method with computer choice
     *       output the game's outcome (returned from scissorcChoice)
     */
    
    
  } // end main
  
  
  /**
   * Lab 9.5
   * 
   * rockChoice(int) -> int
   * 
   * method consumes the computer player's choice (ROCK, PAPER or SCISSORS),
   *   assuming the human player has chosen ROCK
   * method produces game outcome (PLAYER1_WINS, PLAYER2_WINS, or DRAW)
   * 
   * ex1: rockChoice(ROCK) -> DRAW
   * ex2: rockChoice(PAPER) -> PLAYER2_WINS
   * ex3: rockChoice(SCISSORS) -> PLAYER1_WINS
   * ex4: rockChoice(0) -> ERROR
   * ex5: rockChoice(-1) -> ERROR
   * ex6: rockChoice(4) -> ERROR
   * 
   * *** ADD METHOD CODE HERE ***
   */
  
  
  /**
   * Lab 9.6
   * 
   * paperChoice(int) -> int
   * 
   * method consumes the computer player's choice (ROCK, PAPER or SCISSORS),
   *   assuming the human player has chosen PAPER
   * method produces game outcome (PLAYER1_WINS, PLAYER2_WINS, or DRAW)
   * 
   * ex1: paperChoice(ROCK) -> PLAYER1_WINS
   * ex2: paperChoice(PAPER) -> DRAW
   * ex3: paperChoice(SCISSORS) -> PLAYER2_WINS
   * ex4: paperChoice(0) -> ERROR
   * ex5: paperChoice(-1) -> ERROR
   * ex6: paperChoice(4) -> ERROR
   * 
   * *** ADD METHOD CODE HERE ***
   */
  
  
  /**
   * Lab 9.7
   * 
   * scissorsChoice(int) -> int
   * 
   * method consumes the computer player's choice (ROCK, PAPER or SCISSORS),
   *   assuming the human player has chosen SCISSORS
   * method produces game outcome (PLAYER1_WINS, PLAYER2_WINS, or DRAW)
   * 
   * ex1: scissorsChoice(ROCK) -> PLAYER2_WINS
   * ex2: scissorsChoice(PAPER) -> PLAYER1_WINS
   * ex3: scissorsChoice(SCISSORS) -> DRAW
   * ex4: scissorsChoice(0) -> ERROR
   * ex5: scissorsChoice(-1) -> ERROR
   * ex6: scissorsChoice(4) -> ERROR
   * 
   * *** ADD METHOD CODE HERE ***
   */
  
  
} // end class lab

Answer 1