java - 需要帮助结束带有整数用户输入的石头、剪刀、布游戏的 Java 程序的 while 循环

Question

我和我的小组决定为 CSIS 1400 的学期末项目编写一个用于石头、剪刀、布游戏的 Java 程序，并且已经编写了大部分内容，但不确定如何终止 while 循环使用整数用户输入。我们希望用户输入 0 并让循环停止。我们尝试使用 do-while 循环，但我们必须在循环之外初始化 pChoice，这会干扰程序的功能。

这是我们目前为止的代码:

package RPS;

import java.util.Scanner;
import java.util.Random;
//import java.io.Console;
public class Game 
{

public static void main (String[] args) 
{

String username;
String password;

System.out.print ("Username: ");
username = Security.user();

System.out.print ("Password: ");
password = Security.pswd ();

//Console console = System.console ();
//password = new String (console.readPassword ("Password: ")); 

if ( username.equals (Security.jacobUser  ()) && password.equals (Security.jacobPswd  ()) || 
 username.equals (Security.tuckerUser ()) && password.equals (Security.tuckerPswd ()) || 
 username.equals (Security.austinUser ()) && password.equals (Security.austinPswd ())  )
{

Scanner input = new Scanner(System.in);
Random randRoll = new Random();

int choiceArray[] = {1, 2, 3};

System.out.println ("Hello, Welcome to Rock-Paper-Scissors!");
System.out.println ("Here are your choices:");
System.out.printf ("%d for Rock \n", choiceArray[0]);
System.out.printf ("%d for Paper \n", choiceArray[1]);
System.out.printf ("%d for Scissors \n", choiceArray[2]);

String doPlay = "yes";
String dontPlay = "no";
String playChoice;
int choice;

System.out.println ("Do you want to play?");
playChoice = input.nextLine ();

if (playChoice.equals (dontPlay))
{
System.out.println ("Program Terminated");
}

int cChoice;
int pChoice;

int cScore = 0, pScore = 0, tie = 0, rounds = 0;

    while (playChoice.equals (doPlay) || Game.done ().equals (dontPlay))
        {

            System.out.println ("Please make a selection, or use 0 to end the game:");
            cChoice = randRoll.nextInt (3) + 1;
            pChoice = input.nextInt ();

            if (pChoice == choiceArray[0] || pChoice == choiceArray[1] || pChoice == choiceArray[2])
            {



            if (pChoice == cChoice)
                { 
                    System.out.println ("Tie Game!");
                    System.out.println ();
                    tie++;
                    rounds++;
                } 

            else
                {
                    if (cChoice==1 && pChoice==3)
                        {
                            System.out.println ("Computer picked Rock!");
                            System.out.println ("Rock beats Scissors!");
                            System.out.println ("**Computer Wins!**");
                            System.out.println ();
                            cScore++;
                            rounds++;
                        } 

                    if (cChoice==1 && pChoice==2)
                        {
                            System.out.println ("Computer picked Rock!");
                            System.out.println ("Paper beats Rock!");
                            System.out.println ("**Player Wins!**");
                            System.out.println ();
                            pScore++;
                            rounds++;
                        } 

                    if (cChoice==2 && pChoice==3)
                        {
                            System.out.println ("Computer picked Paper!");
                            System.out.println ("Scissors beats Paper!");
                            System.out.println ("**Player Wins!**");
                            System.out.println ();
                            pScore++;
                            rounds++;
                        } 

                    if (cChoice==2 && pChoice==1) 
                        { 
                            System.out.println ("Computer picked Paper!");
                            System.out.println ("Paper beats Rock!");
                            System.out.println ("**Computer Wins!**");
                            System.out.println ();
                            cScore++;
                            rounds++;
                        } 

                    if (cChoice==3 && pChoice==1)  
                        {
                            System.out.println ("Computer picked Scissors!");
                            System.out.println ("Rock beats Scissors!");
                            System.out.println ("**Player Wins!**");
                            System.out.println ();
                            pScore++;
                            rounds++;
                        } 

                    if (cChoice==3 && pChoice==2) 
                        {
                            System.out.println ("Computer picked Scissors!");
                            System.out.println ("Scissors beats Paper!");
                            System.out.println ("**Computer Wins!**");
                            System.out.println ();
                            cScore++;
                            rounds++;
                        }
                }

                System.out.println ("Scores: " + rounds +" rounds:");
                System.out.println ("You\tComputer\tTies");
                System.out.println (" "+ pScore +"\t   " + cScore + "\t\t " + tie);
            }
        }
}
else
{
System.out.println ("Incorrect Credentials");
}
}
}

所有控制台内容都在注释中，因为 netbeans 在运行时会抛出空指针异常，但它在命令行中工作得很好，我们现在只想继续在 IDE 中工作，直到完成。我们还希望它在 playChoice = dontPlay 时终止。

如有任何帮助，我们将不胜感激，谢谢。

这是我们完成的源代码:

package RPS;

import java.util.Scanner;
import java.util.Random;
import java.io.Console;
public class Game 
{

public static void main (String[] args) 
{

System.out.println ("Credentials required.");

String username;
String password;

System.out.print ("Username: ");
username = Security.user();

Console console = System.console ();
password = new String (console.readPassword ("Password: ")); 

if ( username.equals (Security.jacobUser  ()) && password.equals (Security.jacobPswd  ()) || 
 username.equals (Security.tuckerUser ()) && password.equals (Security.tuckerPswd ()) || 
 username.equals (Security.austinUser ()) && password.equals (Security.austinPswd ())  )
{

Random randRoll = new Random();
Scanner input = new Scanner (System.in);   

int choiceArray[] = {1, 2, 3};

System.out.println ("Hello, Welcome to Rock-Paper-Scissors!");
System.out.println ("Here are your choices:");
System.out.printf ("%d for Rock \n", choiceArray[0]);
System.out.printf ("%d for Paper \n", choiceArray[1]);
System.out.printf ("%d for Scissors \n", choiceArray[2]);

int cChoice;
int pChoice;

int cScore = 0, pScore = 0, tie = 0, rounds = 0;


    do
        {

            System.out.println ("Please make a selection, or use 0 to end the game:");
            cChoice = randRoll.nextInt (3) + 1;
            pChoice = input.nextInt ();

            if (pChoice == choiceArray[0] || pChoice == choiceArray[1] || pChoice == choiceArray[2])
            {



            if (pChoice == cChoice)
                { 
                    System.out.println ("Tie Game!");
                    System.out.println ();
                    tie++;
                    rounds++;
                } 

            else
                {
                    if (cChoice==1 && pChoice==3)
                        {
                            System.out.println ("Computer picked Rock!");
                            System.out.println ("Rock beats Scissors!");
                            System.out.println ("**Computer Wins!**");
                            System.out.println ();
                            cScore++;
                            rounds++;
                        } 

                    if (cChoice==1 && pChoice==2)
                        {
                            System.out.println ("Computer picked Rock!");
                            System.out.println ("Paper beats Rock!");
                            System.out.println ("**Player Wins!**");
                            System.out.println ();
                            pScore++;
                            rounds++;
                        } 

                    if (cChoice==2 && pChoice==3)
                        {
                            System.out.println ("Computer picked Paper!");
                            System.out.println ("Scissors beats Paper!");
                            System.out.println ("**Player Wins!**");
                            System.out.println ();
                            pScore++;
                            rounds++;
                        } 

                    if (cChoice==2 && pChoice==1) 
                        { 
                            System.out.println ("Computer picked Paper!");
                            System.out.println ("Paper beats Rock!");
                            System.out.println ("**Computer Wins!**");
                            System.out.println ();
                            cScore++;
                            rounds++;
                        } 

                    if (cChoice==3 && pChoice==1)  
                        {
                            System.out.println ("Computer picked Scissors!");
                            System.out.println ("Rock beats Scissors!");
                            System.out.println ("**Player Wins!**");
                            System.out.println ();
                            pScore++;
                            rounds++;
                        } 

                    if (cChoice==3 && pChoice==2) 
                        {
                            System.out.println ("Computer picked Scissors!");
                            System.out.println ("Scissors beats Paper!");
                            System.out.println ("**Computer Wins!**");
                            System.out.println ();
                            cScore++;
                            rounds++;
                        }
                }
            }
        }while (pChoice != 0); 

        System.out.println ("Here are the final standings.");
        System.out.println ("Rounds: " + rounds);
        System.out.println ("You\tComputer\tTies");
        System.out.println (" "+ pScore +"\t   " + cScore + "\t\t " + tie);
}
else
{
System.out.println ("Incorrect Credentials");
}
    }
} 

安全等级:

 /*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

package RPS;

import java.util.Scanner;

/**
 *
 * @author Jacob, Tucker, Austin
 */
public class Security {

public static String user ()
{
    Scanner input = new Scanner (System.in);
    String username = input.nextLine ();
    return username;
}

public static String pswd ()
{
    Scanner input = new Scanner (System.in);
    String password = input.nextLine ();
    return password;
}

public static String jacobUser ()
{
    String username = "jacob";
    return username;
}

public static String jacobPswd ()
{
    String password = "password";
    return password;
}

public static String tuckerUser ()
{
    String username = "tucker";
    return username;
}

public static String tuckerPswd ()
{
    String password = "password";
    return password;
}

public static String austinUser ()
{
    String username = "austin";
    return username;
}

public static String austinPswd ()
{
    String password = "password";
    return password;
}
}

我们现在在使用 javac 时遇到编译错误。详细信息列在下面的评论中。

Answer 1

处理可重复的用户输入时，实现 Do-While 循环几乎始终是最佳方法

    do {

        System.out.println ("Please make a selection, or use 0 to end the game:");
        cChoice = randRoll.nextInt (3) + 1;
        pChoice = input.nextInt ();

        if (pChoice == choiceArray[0] || pChoice == choiceArray[1] || pChoice == choiceArray[2])
        {
            ...
            // All your normal game stuff
            ...
        }
    }while(pChoice != 0)

pChoice 由第一次循环初始化