如何让Java方法根据两个参数返回布尔值？代码调用异常排查

问题现象 #

调用Parity方法时，布尔变量Parity未随方法返回值更新，无法确认方法返回结果。推测和传入的参数Val1、Val2相关，但不确定。尝试打印Val1、Val2仅能显示数字，无法定位问题。

原代码 #

import java.util.Scanner;
import java.util.Random;
public class DiceRoll
{
public static void main (String[] args)
{
     Scanner scan = new Scanner (System.in);
     Random rand = new Random ();
     
     int gameNumber = 0;
     int compPoint = 0;
     int playerPoint = 0;
     int currentGame = 0;
     int compRoll = 0;
     int playerRoll = 0;
     int compRoll2 = 0;
     int playerRoll2 = 0;
     int sumComp = 0;
     int sumPlayer = 0;
     int Val1 = 0;
     int Val2 =0;
     boolean Parity = false;
     
     System.out.println (" How many games? ");
     gameNumber = scan.nextInt ();
     System.out.println ("Number of games: "+gameNumber);
     
     System.out.println ("Computer Wins: "+compPoint);
     System.out.println ("Player Wins: "+playerPoint);
     System.out.println ("");
     
     currentGame = currentGame+1;
     System.out.println ("Current Game:" +currentGame);
     
     compRoll = DiceRoll(10);
     playerRoll = DiceRoll(10);
     compRoll2 = DiceRoll (10);
     playerRoll2 = DiceRoll (10);
     sumComp = (compRoll + compRoll2);
     sumPlayer = (playerRoll + playerRoll2);
     
     
     System.out.printf ("Computer: %d %d Total: %d \nPlayer: %d %d Total: %d" , compRoll, compRoll2, sumComp, playerRoll, playerRoll2, sumPlayer);
     System.out.println ("");
     
     //parityCheck = Val1;
     if (Parity(Val1, Val2) == true)
     {
          System.out.println ("Parity: True");
     }
     else
     {
          System.out.println ("Parity: False");
     }
     
             
}
public static int DiceRoll (int sides)
{
    int rollTotal = 0 ;
    int minRand = 1;
    int maxRand = sides;
    int range = (maxRand - minRand)+ 1;
     
     rollTotal = (int)(Math.random()* range) +minRand;
     
     return rollTotal;
     
}
public static boolean Parity (int Val1, int Val2)
{
     int evenSum = 0;
     int oddSum = 0;
     int sumComp2 = 0;
     int sumPlayer2 = 0;
     
     sumComp2= Val1;
     sumPlayer2= Val2;
     
    if (sumComp2 %2 == 0 && sumPlayer2 == 0 || sumComp2 %2 == 1 && sumPlayer2 == 1)
     {
          return true;
     }
     else
     {
          return false;
     } 
     
     //return ();
}

问题分析 #

代码存在两处核心错误：

• 参数传递错误：调用Parity方法时传入的是初始值为0的Val1和Val2，而非计算好的sumComp和sumPlayer，导致方法处理无效数据
• 逻辑判断错误：Parity方法中错误检查sumPlayer2 == 0或sumPlayer2 == 1，实际应判断sumPlayer2的奇偶性是否和sumComp2一致

修复后的代码 #

import java.util.Scanner;
import java.util.Random;
public class DiceRoll
{
public static void main (String[] args)
{
     Scanner scan = new Scanner (System.in);
     Random rand = new Random ();
     
     int gameNumber = 0;
     int compPoint = 0;
     int playerPoint = 0;
     int currentGame = 0;
     int compRoll = 0;
     int playerRoll = 0;
     int compRoll2 = 0;
     int playerRoll2 = 0;
     int sumComp = 0;
     int sumPlayer = 0;
     int Val1 = 0;
     int Val2 =0;
     boolean Parity = false;
     
     System.out.println (" How many games? ");
     gameNumber = scan.nextInt ();
     System.out.println ("Number of games: "+gameNumber);
     
     System.out.println ("Computer Wins: "+compPoint);
     System.out.println ("Player Wins: "+playerPoint);
     System.out.println ("");
     
     currentGame = currentGame+1;
     System.out.println ("Current Game:" +currentGame);
     
     compRoll = DiceRoll(10);
     playerRoll = DiceRoll(10);
     compRoll2 = DiceRoll (10);
     playerRoll2 = DiceRoll (10);
     sumComp = (compRoll + compRoll2);
     sumPlayer = (playerRoll + playerRoll2);
     
     
     System.out.printf ("Computer: %d %d Total: %d \nPlayer: %d %d Total: %d" , compRoll, compRoll2, sumComp, playerRoll, playerRoll2, sumPlayer);
     System.out.println ("");
     
     // 修复：传入实际计算的sumComp和sumPlayer
     if (Parity(sumComp, sumPlayer) == true)
     {
          System.out.println ("Parity: True");
     }
     else
     {
          System.out.println ("Parity: False");
     }
     
             
}
public static int DiceRoll (int sides)
{
    int rollTotal = 0 ;
    int minRand = 1;
    int maxRand = sides;
    int range = (maxRand - minRand)+ 1;
     
     rollTotal = (int)(Math.random()* range) +minRand;
     
     return rollTotal;
     
}
public static boolean Parity (int Val1, int Val2)
{
     int sumComp2 = Val1;
     int sumPlayer2 = Val2;
     
     // 修复：判断两者奇偶性是否一致
     return (sumComp2 % 2) == (sumPlayer2 % 2);
}

内容的提问来源于stack exchange，提问作者Tayfrax