写java代码 【问题描述】模拟用钱包购买商品的行为。要求实现一个钱包报警异常类，钱包类，信用卡类以及主类，当钱包现金不够支付的时候用信用卡支付，如果信用卡也不够支付则不够买该商品 【输入形式】 主类首先输入钱包中现金数量，精确到小数点后两位 第二行输入信用卡的信用额度 第三行输入信用卡已透支的额度 第四行开始输入支付额度直到输入字符串或钱包不能支付为止为止 【输出形式】输出支付信息 【样例输入】 2000 5000 1000 500 2300 4000 【样例输出】 Cash payments:500.00,Remaining cash:1500.00,Credit card availability:4000.00 Cash payments:1500.00,Remaining cash:0.00,Credit card availability:4000.00 Credit card payments:800.00,Remaining cash:0.00,Credit card availability:3200.00 Wallet Exception,Insufficient credit card balance to pay!

好的，根据您的问题描述，我可以提供以下Java代码实现：

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

class Wallet {
    private double cash;
    
    public Wallet(double cash) {
        this.cash = cash;
    }
    
    public void payCash(double amount) throws WalletException {
        if (cash < amount) {
            throw new WalletException("Insufficient cash balance to pay!");
        }
        cash -= amount;
        System.out.printf("Cash payments:%.2f,Remaining cash:%.2f,", amount, cash);
    }
    
    public void payCreditCard(double amount, CreditCard creditCard) throws WalletException {
        if (creditCard.availableBalance() < amount) {
            throw new WalletException("Insufficient credit card balance to pay!");
        }
        creditCard.pay(amount);
        System.out.printf("Credit card payments:%.2f,Remaining cash:%.2f,Credit card availability:%.2f,", amount, cash, creditCard.availableBalance());
    }
}

class CreditCard {
    private double creditLimit;
    private double creditUsed;
    
    public CreditCard(double creditLimit, double creditUsed) {
        this.creditLimit = creditLimit;
        this.creditUsed = creditUsed;
    }
    
    public double availableBalance() {
        return creditLimit - creditUsed;
    }
    
    public void pay(double amount) throws WalletException {
        if (availableBalance() < amount) {
            throw new WalletException("Insufficient credit card balance to pay!");
        }
        creditUsed += amount;
    }
}

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        double cash = scanner.nextDouble();
        double creditLimit = scanner.nextDouble();
        double creditUsed = scanner.nextDouble();
        Wallet wallet = new Wallet(cash);
        CreditCard creditCard = new CreditCard(creditLimit, creditUsed);
        while (scanner.hasNextDouble()) {
            try {
                double amount = scanner.nextDouble();
                wallet.payCash(amount);
            } catch (WalletException e1) {
                try {
                    wallet.payCreditCard(amount, creditCard);
                } catch (WalletException e2) {
                    System.out.println(e2.getMessage());
                    break;
                }
            }
        }
        System.out.println("Wallet Exception,No more payments to make!");
    }
}

主要思路与Python代码类似，使用了三个类，分别是`Wallet`（钱包类）、`CreditCard`（信用卡类）和`WalletException`（钱包报警异常类）。其中，钱包类和信用卡类分别定义了现金支付和信用卡支付的方法，并在支付时进行余额判断，如余额不足则抛出钱包异常类。主程序中，先输入钱包中现金数量、信用卡的信用额度和信用卡已透支的额度，然后循环输入支付额度，直到输入字符串或钱包不能支付为止。在循环中，先尝试使用钱包支付，如余额不足则使用信用卡支付，如信用卡余额也不足则抛出钱包异常类。最后，如果循环正常结束，则输出“Wallet Exception,No more payments to make!”。