Question

我正在为我的介绍课程编写项目。我有一个代码，我正在尝试编译，但是在添加PrintWriter之后我很难让它工作。一直运行良好，直到我尝试打印到文本文件。有人可以帮我弄清楚如何让它运行？（另外，如果你发现我的逻辑/布局中有任何错误/尝试包含它！我仍然想自己调试程序，我只能这样做直到它运行：）

尝试:(到目前为止）

import java.util.Scanner; //import scanner
import java.util.Random; //import randomizer
import java.io.*; //needed for throws clause

public class randomLottery
{
    public static void main(String[] args) throws IOException
    {
        String fullName;

        Scanner keyboard = new Scanner( System.in );

        //so we can generate random numbers
        Random rand = new Random();

        //declare a constant number of numbers
        final int LOTTERY_NUMBERS = 5;

        //Retrieve names
        System.out.print("Please enter a first and last name for lottery "
                         + "entry (type 'quit' to end): ");
        fullName = keyboard.nextLine();

        while(!fullName.contains(" "))
        {
            System.out.print("Please enter BOTH a first and last name." 
                             + " Try Again: ");
            fullName = keyboard.nextLine();
        }   

        while(!fullName.contains("quit"))
        {
            //separate first/last name
            String[] parts = fullName.split(" ");
            String firstName = parts[0];    
            String lastName = parts[1];

            //Open the file
            PrintWriter outputFile = new PrintWriter("LotteryEntrants.txt");

            //Print the name onto the file
            outputFile.print(lastName + ", " + firstName + ": ");

            int number;
            for (number = 1; number <= LOTTERY_NUMBERS; number++)
            {
                if (number == LOTTERY_NUMBERS)
                {
                    int lotteryNumber = rand.nextInt(100) + 1;
                    outputFile.println(lotteryNumber);
                }
                else
                {
                    int lotteryNumber = rand.nextInt(100) + 1;
                    outputFile.print(lotteryNumber + ", ");
                }
            }

            //get the next name
            System.out.print("Please enter BOTH a first and last name." 
                              + " Try Again: ");
            fullName = keyboard.nextLine(); 
        }

        //Winning Lottery Numbers
        outputFile.print("The winning numbers are: ");

        int winning;
        for (winning = 1; winning <= LOTTERY_NUMBERS; winning++)
        {
            if (winning == LOTTERY_NUMBERS)
                {
                    int lotteryNumber = rand.nextInt(100) + 1;
                    outputFile.print(lotteryNumber);
                }
            else
                {
                    int lotteryNumber = rand.nextInt(100) + 1;
                    outputFile.print(lotteryNumber + ", ");
                }
        }
    outputFile.close();
    }
}

Answer 1

PrintWriter outputFile = new PrintWriter("LotteryEntrants.txt");

应该在while循环之外（之前）。将它放在循环中意味着它不在while循环之后的outputFile的其他用途范围内。

错误：找不到符号编译（初级java）

1 个答案: