java实现从某账户取款和存款的操作 1)输人存取款金额时，如果非数值型，捕获异常并进行处理(系统异常)。2)操作账户类时，如果取款数大于金额则作为异常处理(自定义异常)。代码是什么

在Java中，我们可以创建一个`Account`类来代表银行账户，然后定义一个`withdraw`方法进行取款操作，一个`deposit`方法进行存款操作，并在其中包含异常处理。下面是一个简单的示例：

import java.text.DecimalFormat;
import java.util.Scanner;

class InsufficientFundsException extends Exception {
    public InsufficientFundsException(String message) {
        super(message);
    }
}

class Account {
    private double balance;

    public Account(double initialBalance) {
        this.balance = initialBalance;
    }

    // 存款方法
    public void deposit(double amount) {
        if (amount > 0) {
            balance += amount;
            System.out.println("Deposit successful. Current balance is " + formatMoney(balance));
        } else {
            throw new IllegalArgumentException("Invalid deposit amount");
        }
    }

    // 取款方法
    public void withdraw(double amount) throws InsufficientFundsException {
        if (amount >= 0 && amount <= balance) {
            balance -= amount;
            System.out.println("Withdrawal successful. Current balance is " + formatMoney(balance));
        } else {
            throw new InsufficientFundsException("Insufficient funds to withdraw the requested amount");
        }
    }

    // 格式化金额显示
    private String formatMoney(double amount) {
        DecimalFormat df = new DecimalFormat("#.00");
        return df.format(amount);
    }
}

public class BankOperations {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        try {
            System.out.print("Enter your initial account balance: ");
            double initialBalance = scanner.nextDouble();
            Account myAccount = new Account(initialBalance);

            while (true) {
                System.out.println("\n1. Deposit\n2. Withdraw\n3. Quit");
                int choice = scanner.nextInt();

                switch (choice) {
                    case 1:
                        System.out.print("Enter deposit amount: ");
                        myAccount.deposit(scanner.nextDouble());
                        break;
                    case 2:
                        System.out.print("Enter withdrawal amount: ");
                        myAccount.withdraw(scanner.nextDouble());
                        break;
                    case 3:
                        System.exit(0);
                        break;
                    default:
                        System.out.println("Invalid option.");
                }
            }
        } catch (NumberFormatException e) {
            System.out.println("Error: Please enter a valid number for the balance or transaction amounts.");
        } catch (InsufficientFundsException e) {
            System.out.println(e.getMessage());
        } finally {
            scanner.close();
        }
    }
}

在这个例子中，用户输入初始余额、选择操作（存款或取款），然后输入相应的金额。如果输入的不是数字，会捕获`NumberFormatException`；如果取款金额超过账户余额，则抛出自定义的`InsufficientFundsException`。