我有一個簡單的問題。
我有一個文本檔案，其中包含以下記錄：
HAMADA 115599
KARIM 224466
BOSY 47896512
此檔案實際上定義了使用者帳戶的使用者名和密碼
現在我寫了一個簡單的代碼來編輯特定使用者的密碼。
這是我的代碼：
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Objects;
import java.util.Scanner;
public class Test6 {
public static void main(String[] args)throws IOException {
String newPassword=null;
boolean checked = true;
File f= new File("C:\\Users\\فاطمة\\Downloads\\accounts.txt");// path to your file
File tempFile = new File("C:\\Users\\فاطمة\\Downloads\\accounts2.txt"); // create a temp file in same path
BufferedWriter writer = new BufferedWriter(new FileWriter(tempFile));
Scanner sc = new Scanner(f);
System.out.println("Change account password !!");
System.out.println("Validate your account please !!");
System.out.printf("Username: ");
Scanner sc2 = new Scanner(System.in);
String username = sc2.next().toUpperCase();
System.out.printf("Old Password: ");
String password = sc2.next();
while(sc.hasNextLine())
{
String currentLine= sc.nextLine();
String[] tokens = currentLine.split(" ");
if(Objects.equals(tokens[0], username) && Objects.equals(tokens[1], password) && checked)
{
sc2.nextLine();
System.out.printf("New Password: ");
newPassword= sc2.nextLine();
if(newPassword.length() >= 6)
{
currentLine = tokens[0]+" "+newPassword;
checked = false;
}
else
System.out.println("Short Password, Password must be at least 6 characters.");
}
else{System.out.println("Wrong username or password .. try again !!");}
writer.write(currentLine + System.getProperty("line.separator"));
}
writer.close();
sc.close();
f.delete();
boolean successful = tempFile.renameTo(f);
if(successful == true)
System.out.println("Your password has been changed successfully.");
else
System.out.println("Error occurred during changing password, please try again.");
}
}
問題是：如果我在檔案中有如上所述的許多記錄，現在它将為每個記錄停止寫入“錯誤的使用者名或密碼”消息。我隻是想讓程式隻在輸入的記錄中說這個消息，然後在程式中停止。如果在檔案中找到記錄，則允許使用者更改該記錄的密碼