Question

我真的需要帮助。我使用BlueJ，它说“可能没有初始化”。我如何解决它？它的 correctNumber 大致是16行。

import java.util.Scanner;
import java.util.Random;

public class NumberGuessingGame {

   public static void main(String[] args) {

        Random randomNumber = new Random();
        int correctNumber; 
        int guessTracker;
        int guessLimit = 6; //the number of tries
        int userInput;
        Scanner in = new Scanner(System.in);
        int game = 1;
        boolean winTracker = false;

        while (1 == game)
               correctNumber  = randomNumber.nextInt(1100); //computer generates a random number, max 100
               userInput = 0;
               guessTracker = 0;


             System.out.println("Hello and welcome to this number guessing game. Please guess the number between 1 and 100 and I will help you by telling you if your guess is too high or low: ");
        while (**correctNumber** != userInput && guessTracker < guessLimit){
                 userInput = in.nextInt();
                 guessTracker++;  


         if (userInput == correctNumber){
            System.out.println("You have won the game! Your reward is a fact game: Did you know the first working camera was invented in 1816! "); //winner message, with a unlocked fact game
            System.out.println("The correct number was " + correctNumber); //the correct number
            System.out.println("It took a total of " + guessTracker + " guesses"); //number of guesses it took the user to guess the right number.


        }

              else if (userInput < correctNumber){
                                   System.out.println("Your number is too low"); //displays that the users guess is too low
                         System.out.println("Please enter your next guess: "); //// user can now eneter their next guess
                      }

                else if (userInput > correctNumber){
            System.out.println("Your number is too high"); //displays that the users guess is too high
            System.out.println("Please enter your next guess: "); // user can now eneter their next guess
            }


        if (correctNumber != userInput){
            System.out.println("Sorry you have run out of guesses! The correct number was: " + correctNumber); // displays the correct number


        }

       }
    }

}

Answer 1

我真的需要帮助。我使用BlueJ，它说“可能没有初始化”。我该如何解决？

本地范围变量需要在使用前初始化（分配初始值）：

int correctNumber = 0

同样适用于您的其他变量。

Answer 2

您需要将correctNumber初始化为一个值。

情况并非总是如此，但想一想：

你调用while(1 == game)然后将correctNumber初始化为一个随机数，correctNumber = randomNumber.nextInt(1100)这会初始化correctNumber，但是当java编译器编译你的应用程序时，它不能确定1 == game是真正。因此，当编译器到达下一个循环while (**correctNumber** != userInput && guessTracker < guessLimit)时，您的编译器会发现correctNumber尚未初始化，即使它是第一个循环。

简而言之，编译器不知道是否会输入循环，因此user3437460在说你需要初始化局部范围变量时是绝对正确的，在这种情况下int correctNumber = 0将完美适合你。

Java猜猜游戏'可能未初始化'

2 个答案: