因此，我已成功将虚假银行帐户信息的用户列表添加到文本文件中。现在我需要把它们读回我的程序。
例如：
如果我输入了用户名 - mattsmith 和PIN - 1234
Matt Smiths的其余账户信息将显示在控制台中，我希望能够做一些事情，比如加钱，查看余额和退出。
最好的方法是什么？
这是我到目前为止的代码
ATM CLASS
public class ATM {
public static void main(String[] args) {
// variables
String dash = "-------------------\n";
int accounts = 0;
Bank bank = new Bank();
boolean login = true;
// Scanner
Scanner scanner = new Scanner(System.in);
// Welcome screen
System.out.print(dash);
System.out.print("Welcome to the Bank\n");
System.out.print(dash);
System.out.println("Do you have an account with us? (y/n) ");
String answer = scanner.nextLine();
if (answer.equalsIgnoreCase("y")) {
while (login) {
System.out.println("Username: ");
String lUsername = scanner.nextLine();
System.out.println("PIN: ");
int lPin = scanner.nextInt();
if (lUsername.equals(SampleUser.myUserName)
&& lPin == SampleUser.myPin) {
login = false;
System.out.println("\nLogin successful\n");
}
}
Bank.menu();
} else {
// new user is created
System.out.println("Enter your full name below (e.g. John M. Smith): ");
String name = scanner.nextLine();
System.out.println("Create a username: ");
String userName = scanner.nextLine();
System.out.println("Enter your starting deposit amount: ");
double balance = scanner.nextInt();
System.out.print(dash);
System.out.print("Generating your information...\n");
System.out.print(dash);
int pin = bank.PIN();
String accountNum = bank.accountNum();
User user = new User(name, userName, pin, accountNum, balance);
// new user gets added to the array list
Bank.users.add(user);
System.out.println(user);
}
try {
File file = new File("users.text");
if (!file.exists()) {
file.createNewFile();
}
FileWriter fw = new FileWriter(file.getAbsoluteFile(), true);
BufferedWriter bw = new BufferedWriter(fw);
bw.append(String.valueOf(Bank.users));
bw.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
银行类
public class Bank {
// Generate a random 16 digit bank account number
public String accountNum() {
int max = 9999;
int min = 1000;
int a1 = (int) (Math.random() * (max - min) + min);
int a2 = (int) (Math.random() * (max - min) + min);
int a3 = (int) (Math.random() * (max - min) + min);
int a4 = (int) (Math.random() * (max - min) + min);
String accountNum = a1 + "-" + a2 + "-" + a3 + "-" + a4;
return accountNum;
}
// Generate a random 4 digit PIN
public int PIN() {
int max = 9999;
int min = 1000;
int PIN = (int) (Math.random() * (max - min) + min);
return PIN;
}
public static void menu() {
while (true) {
System.out.print("\n1"); System.out.print(" - View Balance ");
System.out.print("3"); System.out.print(" - Deposit Money\n");
System.out.print("2"); System.out.print(" - Withdraw Money ");
System.out.print("4"); System.out.print(" - Exit\n\n");
System.out.print("I would like to: \n");
Scanner bscanner = new Scanner(System.in);
int mc = bscanner.nextInt();
if (mc == 1) {
System.out.print("Your current balance is: $" + SampleUser.getMyBalance() + "\n");
} else if (mc == 2) {
System.out.print("Enter withdrawl amount: ");
double wd = bscanner.nextDouble();
SampleUser.myBalance -= wd;
System.out.println("\n$" + SampleUser.getMyBalance() + " is your new account total");
} else if (mc == 3) {
System.out.print("Enter deposit amount: ");
double dp = bscanner.nextDouble();
SampleUser.myBalance += dp;
System.out.println("\n$" + SampleUser.getMyBalance() + " is your new account total");
}
}
}
public static void readFile() {
}
// array list for users
static ArrayList users = new ArrayList(); {
};
}
USER CLASS
public class User implements Serializable{
String name;
String userName;
String accountNum;
int pin;
double balance;
public User (String name, String userName, int pin, String accountNum, double balance) {
this.name = name;
this.userName = userName;
this.accountNum = accountNum;
this.pin = pin;
this.balance = balance;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getAccountNum() {
return accountNum;
}
public void setAccountNum(String accountNum) {
this.accountNum = accountNum;
}
public int getPin() {
return pin;
}
public void setPin(int pin) {
this.pin = pin;
}
public double getBalance() {
return balance;
}
public void setBalance(double balance) {
this.balance = balance;
}
}