Java 我的PrintWriter正在覆盖我打印的每一行。如何让它记录我程序中的所有内容？

当我尝试用PrintWriter记录所有失败的尝试时，它只会覆盖日志中的每一行，而不是在每次尝试失败时在日志中生成多行。我该如何补救？怎么回事

包装HW1

import java.io.File;
import java.io.FileNotFoundException;
import java.io.PrintWriter;
import java.util.Scanner;

public class Banking {

    public static void main(String[] args) throws FileNotFoundException {

    File fi1 = new File("ClientInfo.txt");
    Scanner sc1 = new Scanner(fi1);
    Scanner sc2 = new Scanner(System.in);
    Scanner sc3 = new Scanner(System.in);
    Scanner loginScan = new Scanner(System.in);
    ClientRecords[] clientRecordArray = new ClientRecords[100];
    PrintWriter logTransaction1 = new PrintWriter("BankLogs.txt");

    String firstName;
    String middleName;
    String lastName;
    String userId = "";
    String userIdTyped;
    int pinNumber;
    double balance;
    String choice1;
    int choice2;
    int logSize = 0;
    int failedUserId = 0;





    while(sc1.hasNext())

    {
    firstName = sc1.next();
    middleName = sc1.next();
    lastName = sc1.next();
    userId = sc1.next();
    pinNumber = sc1.nextInt();
    balance = sc1.nextDouble();
    ClientRecords client1 = new ClientRecords(firstName, middleName, lastName, userId, pinNumber, balance);
    clientRecordArray[logSize] = client1;
    logSize++;
    }






    System.out.println("Please enter your user ID:");
    userIdTyped = loginScan.nextLine();


    while(!clientRecordArray[0].getUserId().equals(userIdTyped))  
    {

        userIdTyped = null;
        System.out.println("Wrong user ID please try again:");
        failedUserId++;
        userIdTyped = loginScan.nextLine();


    }

    logTransaction1.println("Failed to enter user ID " + failedUserId + " times.");
    logTransaction1.close();


    menu1(sc2);
    menu2(sc3);





    }  






    public static void menu1(Scanner sc2)
    {
        ClientRecords client1 = new ClientRecords("N", "xx", "uygg", "PinkFloyd111", 0007, 51234.99);
        System.out.println("Please enter the corresponding pin number:");

        int userPin = sc2.nextInt();


        while(userPin != client1.getUserPin())
        {
        System.out.println("Sorry wrong PIN please try again.");
        userPin = sc2.nextInt();
        }




    }






        public static void menu2(Scanner sc3) throws FileNotFoundException
    {

        PrintWriter logTransaction = new PrintWriter("BankLogs.txt");
        ClientRecords client1 = new ClientRecords("hjhh", "hjh", "hh", "PinkFloyd111", 0007, 51234.99);
        int choice = 0;
        double depositAmount = 0;
        double withdrawAmount = 0;
        double balance = client1.getUserBalance();




        System.out.println("Welcome to your bank!");
        System.out.println("Press (1) to deposit to your account. ");
        System.out.println("Press (2) to withdraw from your account. ");
        System.out.println("Press (3) to check balance of your account. ");
        System.out.println("Press (4) to exit the system.");
        System.out.println("Enter the number for your choice here: ");
        choice = sc3.nextInt();


        switch (choice) {
            case 1: 
                System.out.println("Please enter how much you'd like to desposit here:");
                depositAmount = sc3.nextDouble();
                balance += depositAmount;
                System.out.println("You have deposited " + "$" + depositAmount);
                logTransaction.println("Deposit of: " + "$" + depositAmount);
                logTransaction.close();
                break;


            case 2:
                System.out.println("Please enter how much you'd like to withdraw here:");
                withdrawAmount = sc3.nextDouble();
                balance -= withdrawAmount;
                System.out.println("You have withdrawn " + "$" + withdrawAmount);
                logTransaction.println("Withdrawal of: " + "$" + withdrawAmount);
                logTransaction.close();
                break;


            case 3:
                System.out.println("The balance of your account is: " + "$" + balance);
                break;


            case 4: 
                System.out.println("Thank you and have a great day!");


        }







    }

}

每次你打电话

PrintWriter logTransaction = new PrintWriter("BankLogs.txt");

您正在截断文件并重新启动。要追加，需要显式调用FileWriter

PrintWriter logTransaction = new PrintWriter(new FileWriter("BankLogs.txt", true), true);

---

这允许附加到现有文件。另外，第二个true启用自动刷新，因此如果程序崩溃，您丢失数据的可能性更小。

Post a。没别的办法，是的。我是新来的，想边走边学习网站。